JAMB UTME - Physics - 2018
Question 1 Report
Musical instruments playing the same note can be distinguished from one another owing to the difference in their
Answer Details
Different musical instruments playing the same note can be distinguished from one another due to the difference in their "timbre" or "tone color." Timbre refers to the unique character or quality of a sound that allows us to distinguish it from other sounds even when they have the same pitch and loudness. For example, a piano and a guitar playing the same note will sound different due to the differences in their timbre. This is why we can tell the difference between different instruments and why some instruments are better suited to certain styles of music than others.
Question 2 Report
One of the features of the fission process is that
Answer Details
The fission process refers to the splitting of an atomic nucleus into two or more smaller nuclei. One of the key features of the fission process is that it can lead to a chain reaction, where the neutrons released during fission can go on to trigger additional fission reactions. This chain reaction can produce a large amount of energy, as is the case in nuclear power plants and nuclear weapons.
Another feature of the fission process is that it typically produces radioactive products. These products can remain radioactive for a long time, which is why there are concerns about the safe disposal of nuclear waste.
Additionally, the fission process typically releases neutrons, which can go on to cause further fission reactions. This neutron release is an important aspect of the chain reaction mentioned earlier.
Finally, the fission process is accompanied by a small loss of mass, which is converted into energy according to Einstein's famous equation E=mc². This loss of mass is what allows the large amount of energy to be released during a fission reaction.
Question 3 Report
What type of reaction is represented by the following scheme?
\( {}_{1}^{2}X + {}_{1}^{2}Y \longrightarrow {}_{2}^{3}Z + {}_{1}^{0}n + \text{energy} \)
Answer Details
The type of reaction represented by the given scheme is a nuclear fission reaction.
Nuclear fission is a process where a heavy nucleus is split into smaller nuclei with the release of energy. In the given scheme, a heavy element X is split into two lighter elements, Y and Z, along with the release of energy and some neutrons (n).
In a nuclear fission reaction, a neutron is usually absorbed by the nucleus of the heavy element, which then becomes unstable and splits into two smaller nuclei and some neutrons. These neutrons can then go on to split other heavy nuclei, resulting in a chain reaction.
In the given scheme, the release of energy and the presence of neutrons suggest that it is a fission reaction. Moreover, the scheme depicts the process of splitting a heavy element into two lighter elements, which is a characteristic of a fission reaction.
Therefore, the type of reaction represented by the given scheme is a nuclear fission reaction.
Question 4 Report
Which of the following is an essential physical property of the wires uses for making fuses ?
Answer Details
The essential physical property of the wire used for making fuses is low melting point. This means that the wire should have a low temperature at which it melts and breaks, interrupting the flow of electrical current. This is important in a fuse because when there is an overload of electrical current, the wire will melt, breaking the circuit and preventing damage to the electrical system.
The other options, low density, low electrical resistivity, and hypothermal conductivity, are not as important for a fuse wire. Low density is the property of a material to be light, and it doesn't necessarily affect the performance of a fuse wire. Low electrical resistivity is the property of a material to have low resistance to the flow of electrical current, and it doesn't necessarily affect the performance of a fuse wire either. Hypothermal conductivity is the property of a material to conduct heat poorly, and it also doesn't necessarily affect the performance of a fuse wire.
Question 5 Report
An electric heating coil rated at 1KW is used to heat 2kg of water for 2 minutes. The initial water temperature is 30\(^{o}\)C. Taking the specific heat of the water as 4,000Jkg\(^{-1}\) and neglecting that of the container, the final water temperature is
Answer Details
To determine the final temperature of the water, we can use the formula:
Q = mcΔT
where Q is the heat transferred, m is the mass of the water, c is the specific heat capacity of water, and ΔT is the change in temperature.
We know that the power of the electric heating coil is 1KW, which means it transfers 1000 Joules of energy per second. In 2 minutes, or 120 seconds, it transfers 120,000 Joules of energy to the water.
The mass of the water is given as 2kg and the specific heat capacity of water is 4000 J/kg°C. We can assume that the initial temperature of the water is 30°C.
Using the formula, we can solve for the change in temperature:
120,000 J = (2 kg)(4000 J/kg°C)(ΔT)
ΔT = 15°C
Therefore, the final temperature of the water is 30°C + 15°C = 45°C.
So, the final water temperature is 45.0oC.
Question 6 Report
In the diagram shown, which of the simple pendulum will resonate with P when set into oscillation?
Answer Details
Question 7 Report
In the diagram shown, If the south-poles of two magnets stroke a steel bar, the polarities at T and V will respectively be
Answer Details
Question 8 Report
The force between the molecules of a liquid in contact with that of a solid is?
Answer Details
(ii) Adhesion : The force of attraction between unlike molecules, i.e. between the molecules of different liquids or between the molecules of a liquid and those of a solid body when they are in contact with each other, is known as the force of adhesion. This force enables two different liquids to adhere to each other or a liquid to adhere to a solid body or surface.
Question 9 Report
Convex mirrors are used as driving mirrors because images formed are
Answer Details
Convex mirrors are used as driving mirrors because the images formed by them are "erect, virtual, and diminished."
Let me explain what these terms mean:
- Erect: It means that the image appears upright, just like the actual object. This is important for a driving mirror because it allows the driver to perceive the correct orientation of the vehicles behind them.
- Virtual: It means that the image appears to be behind the mirror, and not in front of it. This is also important for a driving mirror because it allows the driver to see a wider field of view without having to turn their head.
- Diminished: It means that the image is smaller than the actual object. This is important for a driving mirror because it allows the driver to see a larger area behind them while still fitting it within the mirror's frame.
Overall, these properties make convex mirrors ideal for use as driving mirrors as they provide the driver with an accurate view of the vehicles behind them without sacrificing their field of view.
Question 10 Report
A particle of mass M initially at rest splits into two. If one of the particles of mass M1 moves with velocity V1 , the second particle moves with velocity
Answer Details
When a particle of mass M splits into two, the total mass is conserved, and so the sum of the masses of the two resulting particles must be equal to M. If one of the particles of mass M1 moves with velocity V1, we can use the law of conservation of momentum to determine the velocity of the second particle.
The law of conservation of momentum states that the total momentum of a system of particles remains constant if no external forces act on the system. In this case, the initial momentum of the system is zero, since the particle was initially at rest. After the particle splits, the momentum of the system is the sum of the momenta of the two resulting particles.
Let's use the subscript 1 to represent the first particle of mass M1 and the subscript 2 to represent the second particle of mass M-M1. By conservation of momentum, we have:
0 = M1*V1 + (M - M1)*V2
Solving for V2, we get:
V2 = -M1/M*(V1)
Therefore, the second particle moves in the opposite direction with velocity -M1/M*(V1). This means that the two particles move in opposite directions, with the ratio of their velocities determined by the ratio of their masses. Option (D) in the table shows the correct answer, which is -M1/M*(V1).
Question 11 Report
In a series R-L-C circuit at resonance, the voltages across the resistor and the inductor are 30V and 40V respectively. What is the voltage across the capacitor?
Answer Details
Question 12 Report
A car traveled at a uniform speed of 100km/h, spends 15m moving from point A to point B along its route. The distance between A and B is
Answer Details
To calculate the distance between point A and point B, we can use the formula:
Distance = Speed x Time
where the speed is given as 100 km/h and the time is given as 15 minutes, which we need to convert to hours.
1 hour = 60 minutes, so 15 minutes = 15/60 hours = 0.25 hours.
Now, we can substitute these values into the formula:
Distance = 100 km/h x 0.25 h = 25 km
Therefore, the distance between point A and point B is 25 km.
is the correct answer.
Question 13 Report
In the diagram given if the atmospheric pressure is 760mm, the pressure in the chamber G Is
Answer Details
Question 14 Report
A narrow beam of white light can be split up into different colours by a glass prism. The correct explanation is that
Answer Details
The correct explanation for why a narrow beam of white light can be split up into different colors by a glass prism is that different colors of white light travel with different speeds in glass.
White light is made up of different colors with different wavelengths, ranging from violet to red. When a narrow beam of white light passes through a glass prism, the different colors refract at slightly different angles due to the fact that their wavelengths are different. This causes the different colors to spread out and form a spectrum.
The amount of refraction that occurs depends on the speed of light in the medium. Different colors of light have different speeds in glass due to the fact that their wavelengths are different. This means that they will refract at different angles as they pass through the glass prism, causing them to spread out.
So, the correct explanation for why a narrow beam of white light can be split up into different colors by a glass prism is that different colors of white light travel with different speeds in glass. Therefore, is the correct explanation.
is incorrect because it describes what white light is made up of, but does not explain how it is split up into colors by a prism.
is incorrect because a prism does not have all the colors of white light, but rather it separates the colors that are already present in white light.
is incorrect because total internal reflection occurs when light is completely reflected back into the same medium, which is not what happens when white light is split up by a prism.
Question 15 Report
For what values of F and ? will the forces shown in the diagram below be in equilibrium.
Answer Details
Resolve vertically, 40cos? = 20, ? = 60o
Resolve horizontally, f = 40sin? = 40sin60o
= 40(?32 )
= 20?3 N
Resolve horizontally, f = 40sin? = 40sin60o
= 40(?32 )
= 20?3 N
Question 16 Report
The inner diameter of a small test tube can be measured accurately using a
Answer Details
A vernier caliper is a measuring device used to precisely measure linear dimensions. It is a very useful tool to use when measuring the diameter of a round objects like cylinders because the measuring jaws can be secured on either side of the circumference.
Vernier calipers have both a fixed main scale and a moving vernier scale. The main scale is graduated in either millimetres or tenths of an inch. The vernier scale allows much more precise readings to be taken (usually to the nearest 0.02mm or 0.001 inch) in comparison to a standard ruler (which only measures to th nearest 1mm or 0.25 inch).
The vernier scale was invented by French mathematician Pierre Vernier in 1631. As part of the vernier caliper, it is used together with the main scale, and helps to provide very precise measurements. Vernier calipers usually show either imperial or metric measurements, but some measure in both.
Vernier calipers have both a fixed main scale and a moving vernier scale. The main scale is graduated in either millimetres or tenths of an inch. The vernier scale allows much more precise readings to be taken (usually to the nearest 0.02mm or 0.001 inch) in comparison to a standard ruler (which only measures to th nearest 1mm or 0.25 inch).
The vernier scale was invented by French mathematician Pierre Vernier in 1631. As part of the vernier caliper, it is used together with the main scale, and helps to provide very precise measurements. Vernier calipers usually show either imperial or metric measurements, but some measure in both.
Question 17 Report
What flows to the earth by connecting the conductor to the earth?
Answer Details
When a conductor is connected to the earth, electrons flow to the earth. Electrons are negatively charged particles that are present in all conductors. When a conductor is connected to the earth, it creates a path for electrons to flow from the conductor to the earth, which helps to balance the electric potential and prevent the buildup of electric charge. This flow of electrons is known as grounding and is an important safety measure in electrical systems.
Question 18 Report
What effort will a machine of efficiency 90% apply to a load of 180N if its efforts arm is twice as long as its load arm?
Answer Details
Question 19 Report
An object is placed 20cm from a concave mirror of focal length 10cm. The linear magnification of the image produced is?
Answer Details
The linear magnification of an image is given by the formula:
magnification = height of image / height of object = -v/u
where v is the image distance, u is the object distance, and the negative sign indicates that the image is inverted.
In this problem, the object is placed 20cm from a concave mirror of focal length 10cm. Since the object is placed beyond the focal point, the image will be real and inverted.
Using the mirror formula 1/f = 1/v + 1/u, we can find the image distance v:
1/10 = 1/v + 1/20
Solving for v, we get:
v = -20 cm
Now, we can use the magnification formula to find the linear magnification:
magnification = -v/u = -(-20)/20 = 1
Therefore, the linear magnification of the image produced is 1, which means the image is the same size as the object and is also inverted.
The answer is: 1.
Question 20 Report
Temperature is the property of a body which is proportional to the ____.
Answer Details
Temperature is proportional to the average kinetic energy of the molecules in a body. This means that as the average kinetic energy of the molecules increases, so does the temperature.
Think about it like this: the hotter an object, the more energy its molecules have. This energy is what makes the molecules move faster, and therefore, the temperature of the object increases.
The average kinetic energy of the molecules is a better measure of temperature than the maximum speed of the molecules because temperature is a measure of the overall energy distribution, not just the energy of a single molecule.
Question 21 Report
A force of 5N acts at a point Y on a rod XYZ as shown in this diagram. If XYZ is 2m, what is the moment of the force about point X?
Answer Details
To find the moment of the force about point X, we need to first understand what moment is. Moment is the turning effect of a force around a pivot point. It is calculated by multiplying the force by the perpendicular distance between the pivot point and the line of action of the force.
In this case, the force of 5N is acting on the rod at point Y. To find the moment of this force about point X, we need to find the perpendicular distance between point X and the line of action of the force.
From the diagram, we can see that the perpendicular distance between point X and the line of action of the force is 2m (the length of the rod). So, the moment of the force about point X is:
Moment = force x perpendicular distance
= 5N x 2m
= 10Nm
Therefore, the correct answer is: 10Nm.
Question 22 Report
The photo cell works on the principle of the
Answer Details
The photocell works on the principle of the emission of electrons by incident radiation. In simple terms, a photocell is a device that converts light energy into electrical energy. It does this by using a material (such as silicon) that releases electrons when it is exposed to light. These electrons can then be collected and used to produce a current, which can be used to power an electrical device. The more light that hits the photocell, the more electrons are released and the greater the electrical current.
Question 23 Report
Which of the following phenomena cannot be explained by the molecular theory of matter?
Answer Details
Conduction: the flow of internal energy from a region of higher temperature to lower temperature
Convection: heat transfer due to bulk movement of molecules within fluids
Expansion: the action of becoming larger or more extensive
Convection: heat transfer due to bulk movement of molecules within fluids
Expansion: the action of becoming larger or more extensive
Question 24 Report
The differences observed in solids, liquids and gases may be accounted for by
Answer Details
The differences observed in solids, liquids, and gases can be accounted for by the spacing and forces acting between the molecules.
In a solid, the molecules are packed closely together, so they have a fixed shape and volume. The intermolecular forces are strong enough to keep the molecules in a fixed position relative to one another.
In a liquid, the molecules are still close together, but they are free to move around each other. The intermolecular forces are weaker than in a solid, so the molecules can slide past one another, giving the liquid its ability to flow and take the shape of its container.
In a gas, the molecules are widely spaced and are in constant motion. The intermolecular forces are very weak, so the molecules are free to move around and fill any available space. Gases have no fixed shape or volume.
So, the differences observed in solids, liquids, and gases can be explained by the spacing and forces acting between the molecules. It's not about their relative masses, melting points, or the different molecules in each of them.
Question 25 Report
The process by which protons are converted into helium atoms with a tremendous release of energy is called?
Answer Details
The process by which protons are converted into helium atoms with a tremendous release of energy is called "thermonuclear fusion".
In this process, two light atomic nuclei combine to form a heavier nucleus, releasing a huge amount of energy in the form of light and heat. This is the same process that powers the sun and other stars. The high temperatures and pressures required for fusion to occur can only be achieved in stars or in controlled environments such as fusion reactors.
Thermonuclear fusion is different from nuclear fission, which is the process of splitting a heavy nucleus into lighter nuclei with the release of energy.
Thermionic emission and photoelectric emission are different processes that involve the emission of electrons from a material due to heating or exposure to light, respectively.
Question 26 Report
Which of the following obeys Ohm's law?
Answer Details
Ohm's law states that the current passing through a conductor is directly proportional to the voltage applied across it, given the temperature and other physical conditions remain constant.
Among the given options, only "all metals" obey Ohm's law. This is because metals have a linear relationship between their resistance and the applied voltage, meaning that the resistance of a metal remains constant regardless of the voltage applied. As a result, the current passing through a metal is directly proportional to the voltage applied, following Ohm's law.
On the other hand, a diode, all electrolytes, and glass do not obey Ohm's law. A diode is a semiconductor that has a non-linear current-voltage relationship, and its resistance is not constant. Similarly, electrolytes and glass are non-metallic substances that do not have a linear relationship between their resistance and the applied voltage. Their resistance can change significantly with the voltage applied, and hence they do not follow Ohm's law.
Question 27 Report
Calculate the effective capacitance of the circuit in the diagram given
Answer Details
The three 2uf capacitors are in parallel to each other so u add them like this
2uf+2uf+2uf=6uf
So u have three capacitors in series
6uf 2uf and 3uf
They are in series so
1/C= 1/6+1/3=1/2
C=2uf
Then the same thing with the last two capay
1/2+1/2=1uf
Thanks
2uf+2uf+2uf=6uf
So u have three capacitors in series
6uf 2uf and 3uf
They are in series so
1/C= 1/6+1/3=1/2
C=2uf
Then the same thing with the last two capay
1/2+1/2=1uf
Thanks
Question 28 Report
A body of mass 100g moving with a velocity if 10ms-1 collides with a wall. If after collision it moves with a velocity of 2.0ms−1 in the opposite direction, calculate the change in momentum.
Answer Details
Momentum = Mass x Velocity
Change in Momentum = Mass x (change in velocity)
Change in Momentum = Mass x (v - u)
Mass = 100g = 0.1kg
U = 2ms−1
V = 10ms−1
Change in momentum = m (v − u)
= 0.1 (10 − 2)
= 0.1 (8)
= 0.8Ns
Change in Momentum = Mass x (change in velocity)
Change in Momentum = Mass x (v - u)
Mass = 100g = 0.1kg
U = 2ms−1
V = 10ms−1
Change in momentum = m (v − u)
= 0.1 (10 − 2)
= 0.1 (8)
= 0.8Ns
Question 29 Report
The process whereby a liquid turns spontaneously into vapour is called
Answer Details
The process whereby a liquid turns spontaneously into vapor is called evaporation.
Evaporation is the process by which a liquid changes into a gas at a temperature below its boiling point. This happens when the molecules of the liquid gain enough energy to escape from the surface of the liquid into the air as a gas. The rate of evaporation depends on factors such as the temperature, the humidity of the air, and the surface area of the liquid. For example, a shallow pool of water will evaporate faster than a deep one because it has a larger surface area.
Boiling, on the other hand, is the process by which a liquid changes into a gas at its boiling point. This happens when the pressure of the gas generated by the boiling liquid is equal to the atmospheric pressure. The temperature remains constant during boiling.
Regelation and sublimation are different processes altogether. Regelation is the process by which a solid changes into a liquid when it is subjected to pressure. Sublimation is the process by which a solid changes directly into a gas, bypassing the liquid state.
Question 30 Report
Mercury which is spilled onto a glass surface forms ball-like shapes because____.
Answer Details
In case of small drops of mercury, the gravitational potential energy is negligible in comparison to the potential energy due to surface tension.Consequently, to keep the drop in equilibrium, the mercury drop’s surface tends to contract so that its surface area will be the least for a sphere and the drops will be spherical.
But in the case of bigger drops of mercury, the potential energy due to gravity is predominant over the potential energy due to surface tension.Consequently, to keep equilibrium , the mercury drop tends to assume minimum potential energy as possible, the drop becomes oval in shape and lower center of gravity.
But in the case of bigger drops of mercury, the potential energy due to gravity is predominant over the potential energy due to surface tension.Consequently, to keep equilibrium , the mercury drop tends to assume minimum potential energy as possible, the drop becomes oval in shape and lower center of gravity.
Question 31 Report
A ball of mass 800g moving horizontally with a speed of 5m/s hits a vertical wall and rebounds with the same speed. The impulse experienced by the ball is?
Answer Details
The impulse experienced by the ball can be calculated using the principle of conservation of momentum, which states that the total momentum before the collision is equal to the total momentum after the collision. In this case, the momentum of the ball before the collision is:
p1 = m * v1
where m is the mass of the ball and v1 is its velocity before the collision. Substituting the values given in the problem, we get:
p1 = 0.8 kg * 5 m/s = 4 kg m/s
After the collision, the ball rebounds with the same speed but in the opposite direction, so its velocity after the collision is:
v2 = -5 m/s
The momentum of the ball after the collision is:
p2 = m * v2
Substituting the values, we get:
p2 = 0.8 kg * (-5 m/s) = -4 kg m/s
The negative sign indicates that the direction of the momentum is opposite to that before the collision.
The change in momentum of the ball is given by:
Δp = p2 - p1
Substituting the values, we get:
Δp = (-4 kg m/s) - (4 kg m/s) = -8 kg m/s
The negative sign indicates that the impulse experienced by the ball is in the opposite direction to its initial momentum, which is the direction of the wall. Therefore, the impulse experienced by the ball is 8 kg m/s.
Therefore, the correct option is: 8kgm/s.
Question 32 Report
The linear expansivity of brass is \(2 \times 10^{-5}\,\text{C}^{-1}\). If the volume of a piece of brass is 15.00cm at 0°C, what is the volume at 100°C
Answer Details
The linear expansivity of brass is given as 2 x 10^-5 /°C. This means that for every 1°C increase in temperature, the brass expands by 2 x 10^-5 of its original size.
To find the new volume of the brass at 100°C, we need to take into account the expansion in all three dimensions (length, width, and height). Since the expansivity given is for length only, we need to find the expansivity in all three dimensions by multiplying it by 3.
The expansivity in all three dimensions is:
3 x (2 x 10^-5 /°C) = 6 x 10^-5 /°C
To find the new volume, we can use the formula:
Vf = Vi (1 + αΔT)
where Vf is the final volume, Vi is the initial volume, α is the expansivity in all three dimensions, and ΔT is the change in temperature.
Plugging in the values, we get:
Vf = 15.00 cm3 (1 + (6 x 10^-5 /°C) x (100°C - 0°C))
Vf = 15.09 cm3
Therefore, the volume of the brass at 100°C is 15.09 cm3.
Question 33 Report
A beam of light is incident from air to water at an angle of 300. Find the angle of refraction if the refractive index of water is 4/3
Answer Details
X = 43
r = ?
Shell?s law:. 7 = Sin20Sinr0
Vg = Sin300Sinr0
Sinr0 = 3Sin3004
Sin r0 = 0.375
R o = Sin-1 (0.375)
R o = 22.02 o
R o = 22 o
Shell?s law:. 7 = Sin20Sinr0
Vg = Sin300Sinr0
Sinr0 = 3Sin3004
Sin r0 = 0.375
R o = Sin-1 (0.375)
R o = 22.02 o
R o = 22 o
Question 34 Report
The electrochemical equivalent of silver is 0.0012g/C. If 36.0g of silver is to be deposited by electrolysis on a surface by passing a steady current for 5mins, the current must be?
Answer Details
The electrochemical equivalent of silver is a measure of the amount of silver that is deposited on a surface per unit of charge. In this case, the electrochemical equivalent of silver is 0.0012 grams per Coulomb of charge. To deposit 36.0 grams of silver by electrolysis, we need to know the amount of charge that must be passed through the solution.
The amount of charge is given by:
Q = m/z
where m is the mass of silver to be deposited, 0.0012 is the electrochemical equivalent of silver, and z is the charge on one mole of electrons (z = 1 for a single electron).
So, the amount of charge required is:
Q = 36.0 g / 0.0012 g/C = 30000 C
The current, I, is given by:
I = Q / t
where t is the time for which the current is flowing. In this case, t = 5 minutes.
So, the current required is:
I = 30000 C / (5 x 60 s) = 100 A
Therefore, the current must be 100 Amperes.
Question 35 Report
In homes, electrical appliances and lamps are connected in parallel because
Answer Details
Question 36 Report
If the focal length of a camera is 20cm, the distance from the film at which the lens must be set to produce a sharp image of 100cm away is
Answer Details
F = 20cm
V = 100cm
U = ?
1U + 1V = 1F
120 + 1100 = 1F
5+1100 = 1F
F = 1006
= 16.7cm
= 17cm
V = 100cm
U = ?
1U + 1V = 1F
120 + 1100 = 1F
5+1100 = 1F
F = 1006
= 16.7cm
= 17cm
Question 37 Report
Electrical appliances in homes are normally earthed so that
Answer Details
Electrical appliances in homes are normally earthed so that a person touching the appliances is safe from electric shock. Earthing provides a safety mechanism by connecting the metal case of an electrical appliance to the earth through a conductor. In the event of a fault in the appliance, such as a short circuit, the current will flow through the earth wire instead of the person's body, preventing electric shock. By connecting the metal case of an appliance to the earth, the potential difference (PD) between the appliance and the earth is reduced to zero, ensuring that the appliance is maintained at a lower PD than the earth. Therefore, "the appliances are maintained at a lower pd than the earth" is the correct answer.
Question 38 Report
The critical angle for light travelling from a transparent medium to air s measured as 340. The refractive index of the medium is
Answer Details
The critical angle is the angle of incidence at which light is just able to pass through the interface between two media and not reflect back. When light travels from a medium with a higher refractive index to a medium with a lower refractive index, it slows down and bends towards the normal. If the angle of incidence is increased, the light will eventually reach a point where it will not be able to escape the higher index medium and will be totally reflected back. This is the critical angle.
The formula for the critical angle can be expressed as follows:
sin(θc) = n2/n1
Where θc is the critical angle, n1 is the refractive index of the first medium, and n2 is the refractive index of the second medium. In this case, the first medium is the transparent medium and the second medium is air, which has a refractive index of approximately 1.
By substituting the value of sin(θc) with the value of 340, and n2 with 1, we can solve for n1.
sin(340) = n1/1
n1 = 1/sin(340)
The value of n1 calculated using this formula is approximately 1.79, which means that the refractive index of the transparent medium is 1.79.
Question 39 Report
Which of the following is not a product of nuclear fusion?
Answer Details
Neutron is not a product of nuclear fusion. Nuclear fusion is the process by which two or more atomic nuclei come together to form a heavier nucleus, releasing a large amount of energy in the process. In most fusion reactions, the resulting products are alpha particles (helium nuclei) and energy in the form of gamma rays.
X-rays and gamma rays are both forms of high-energy electromagnetic radiation that can be produced by nuclear reactions, including nuclear fusion. Alpha particles are also a common product of nuclear fusion, especially in the fusion reactions that power the sun.
However, neutrons are not typically produced in fusion reactions. In fact, one of the major challenges in developing fusion as a practical energy source is finding ways to produce and control the high-energy neutrons that are generated in the process. Neutrons can be produced in some types of fusion reactions, but they are not a primary product.
In summary, neutron is not a product of nuclear fusion, while X-rays, Y-rays (assuming this is a valid form of radiation), and alpha particles are common products of this process.
Question 40 Report
The product of force and time is?
Answer Details
The product of force and time is known as impulse.
Impulse can be defined as the change in momentum that an object experiences as a result of a force being applied to it over a period of time. In simpler terms, impulse is the "push" that an object receives from a force acting on it for a certain amount of time. The more force applied, or the longer the time the force is applied, the greater the impulse and the greater the change in momentum of the object.
It's important to note that impulse is a vector quantity, meaning it has both magnitude and direction. Impulse is a measure of the ability of a force to cause an object to change its velocity, and can be used to explain many phenomena in physics, such as why a heavy object is harder to stop than a lighter one, or why a soccer ball changes direction when it is kicked.
