JAMB UTME - Physics - 2023

Detalhes da Resposta

Let mb=mass of empty bottle,

mw ${𝑚}_{𝑤}$=mass of water only and

ma ${𝑚}_{𝑎}$= mass of alcohol only
 

given; mb ${𝑚}_{𝑏}$=19g



mb ${𝑚}_{𝑏}$ + mw ${𝑚}_{𝑤}$ = 66g

mb ${𝑚}_{𝑏}$ + ma ${𝑚}_{𝑎}$ = ?

R.d=0.8

R.d=mass of alcohol

massofalcoholmassofequalvolumeofwater $\frac{𝑚𝑎𝑠𝑠𝑜𝑓𝑎𝑙𝑐𝑜ℎ𝑜𝑙}{𝑚𝑎𝑠𝑠𝑜𝑓𝑒𝑞𝑢𝑎𝑙𝑣𝑜𝑙𝑢𝑚𝑒𝑜𝑓𝑤𝑎𝑡𝑒𝑟}$

mass of equal volume of water = mw ${𝑚}_{𝑤}$=66-19=47g

0.8 = ma47 $\frac{{𝑚}_{𝑎}}{47}$


ma ${𝑚}_{𝑎}$=0.8×47 =37.6g

 mb ${𝑚}_{𝑏}$ + ma ${𝑚}_{𝑎}$ = 19+37.6=56.6g

Detalhes da Resposta

A wave that is both mechanical and longitudinal is sound waves.

Sound waves are created by the vibration of an object, such as a speaker, which causes the air particles around it to vibrate. These vibrations then travel through the air in the form of a wave.

Sound waves are classified as mechanical waves because they require a medium, such as air, water, or solid objects, to travel through. Without a medium, sound waves cannot propagate.

Furthermore, sound waves are classified as longitudinal waves because the particles in the medium vibrate parallel to the direction of the wave. This means that as the sound wave travels, the particles in the medium move back and forth in the same direction as the wave itself.

In contrast, water waves and seismic waves are mechanical waves, but they are not longitudinal. Water waves are categorized as transverse waves because the particles in the water move up and down at right angles to the direction of the wave. Seismic waves, which include earthquake waves, can be both transverse and longitudinal, but typically the primary seismic waves are classified as transverse waves.

Lastly, light waves are not mechanical waves but rather electromagnetic waves. They do not require a medium to travel through and can propagate in a vacuum, unlike sound waves.

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T=800N; I=50cm=0.5m,

m=10g=0.01kg

fundamental freq: fo ${\mathrm{<br>}}_{}$ =?

fo ${\mathrm{<br>}}_{}$ = 121√Tμ $\frac{1}{21}<br>$

μ =m1 $\frac{\mathrm{<br>}}{}$=0.010.5 $\frac{0.01}{0.5}$

⇒ fo ${\mathrm{<br>}}_{}$ =12×0.5 $\frac{1}{2\times 0.5}$√8000.02 $\frac{800}{0.02}$

                  fo ${\mathrm{<br>}}_{}$  ⇒√ 40,000

⇒1st overtone = 2fo ${\mathrm{<br>}}_{}$ =2×200 = 400Hz

⇒2nd overtone =3fo ${\mathrm{<br>}}_{}$ =3×200=600Hz

∴3rd over tone= 4fo ${\mathrm{<br>}}_{}$  =4×200=800Hz

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To find the effort E required to lift the load, we first need to understand the concept of mechanical efficiency in levers.
A lever is a simple machine that consists of a rigid beam (lever arm) that pivots around a fixed point called the fulcrum. In this case, the fulcrum is point P.
The mechanical efficiency of a lever is defined as the ratio of the output work done (load lifted) to the input work done (effort applied). Mathematically, it can be expressed as:
Efficiency = (Output Work / Input Work) * 100%
In this problem, the load is the output work and the effort is the input work.
Given: Load = 200 kg Length of lever (distance between fulcrum and load) = 10 m Efficiency = 80% Gravitational acceleration (g) = 10 m/s^2
To calculate the effort, let's first calculate the output work:
Output Work = Load * Distance lifted
The distance lifted is equal to the length of the lever arm, which is 10 m.
Output Work = 200 kg * 10 m = 2000 kg·m
Since 1 kg·m is equivalent to 10 J (1 Joule), we can convert the units:
Output Work = 2000 kg·m * 10 J/kg·m = 20000 J
Now, let's calculate the input work:
Input Work = Effort * Distance moved by the effort
The distance moved by the effort is the length of the lever arm, which is 110 m.
Input Work = Effort * 110 m
Using the formula for mechanical efficiency, we can rewrite it as:
Efficiency = (Output Work / Input Work) * 100%
Solving for the effort:
Effort = (Output Work / (Efficiency/100)) / Distance moved by the effort
Effort = (20000 J / (80/100)) / 110 m
Simplifying the equation:
Effort = (20000 J / 0.8) / 110 m
Effort = 250 J / m
Given that g = 10 m/s^2, we know that 1 N = 1 kg·m/s^2. Therefore, we can convert the units:
Effort = (250 J / m) / (1 kg·m/s^2 / 1 N)
Effort = 250 N
Therefore, the effort E required to lift the load is 250 N.

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The number of holes in an intrinsic semiconductor is equal to the number of free electrons.

In an intrinsic semiconductor, the valence band is completely filled with electrons. However, due to thermal energy, some of these electrons can gain enough energy to jump to the conduction band, leaving behind holes in the valence band.

For every electron that moves to the conduction band, a hole is created in the valence band. Since the number of electrons and holes is equal, the number of holes in an intrinsic semiconductor is equal to the number of free electrons.

Therefore, the correct option is: is equal to the number of free electrons.

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Detalhes da Resposta

Electrical conduction of gas is applied in:
(i) The identification of gases
(ii) Lighting/fluorescent tubes
(iii) Advertising industry/Neon signs
(iv) Cathode ray oscilloscope/T.V. tubes

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Detalhes da Resposta

The penetrating power of alpha rays, beta rays, and gamma rays varies greatly. Alpha particles can be blocked by a few pieces of paper. Beta particles pass through paper but are stopped by aluminum foil. Gamma rays are the most difficult to stop and require concrete, lead, or other heavy shielding to block them.

Therefore, X = γ-ray; Y = α-particle; Z = β-particle

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The working of the beam balance is based on the principle of moments.

Moments, also known as torques, are a measure of the turning effect of a force. In the case of the beam balance, it is the moments that help determine the equilibrium or balance of the system.

The beam balance consists of a beam or lever that is supported at a pivot point called the fulcrum. On either end of the beam, there are pans where the objects to be weighed are placed.

When objects of different weights are placed on the pans, the beam becomes unbalanced. This causes the beam to tilt towards the side with the heavier object. However, in order to achieve equilibrium or balance, the moments on both sides of the beam must be equal.

The moment of a force is calculated by multiplying the magnitude of the force by the perpendicular distance from the point of rotation (the fulcrum) to the line of action of the force.

By adjusting the position of the counterweights or by moving the objects on the pans, the moment on each side of the beam can be balanced, resulting in the beam becoming level or horizontal. This indicates that the weights on both sides are equal.

Therefore, the beam balance operates on the principle of moments, where the balance is achieved by equalizing the moments on both sides of the fulcrum.

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The wave number of a wave is defined as the number of wavelengths per unit distance. It represents the spatial frequency of the wave.
In this case, the wave has a frequency of 16 Hz, which means it completes 16 cycles or oscillations per second. Each cycle corresponds to one wavelength.
The wave speed is given as 20 m/s, which is the speed at which the wave propagates through the medium.
To calculate the wave number, we can use the formula:
Wave number (k) = 2? / wavelength (?)
First, we need to find the wavelength of the wave. We can use the formula:
Wave speed (v) = frequency (f) x wavelength (?)
Rewriting the formula, we have:
Wavelength (?) = wave speed (v) / frequency (f)
Substituting the given values, we have:
Wavelength (?) = 20 m/s / 16 Hz
Simplifying the expression, we get:
Wavelength (?) = 1.25 m
Now, we can calculate the wave number using the formula:
Wave number (k) = 2? / wavelength (?)
Substituting the value of the wavelength, we get:
Wave number (k) = 2? / 1.25 m
Simplifying the expression, we get:
Wave number (k) ? 5.03
Therefore, the wave number of the wave is approximately 5.

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To find the terminal p.d. (potential difference), we need to consider the concept of voltage in a circuit. Voltage is the amount of electrical energy per unit charge provided by a power source, in this case, the battery.

In this problem, we are given:

EMF (electromotive force) of the battery = 24.0 V

Internal resistance of the battery = 1.0 Ω

External resistor = 5.0 Ω

When the battery is connected to the external resistor, a current will flow in the circuit. This current is determined by Ohm's law, which states that the current flowing in a circuit is directly proportional to the voltage applied and inversely proportional to the resistance:

I = V / R

where:

I is the current flowing in the circuit

V is the voltage applied

R is the resistance of the circuit

In this case, the voltage applied is the emf of the battery, and the resistance is the sum of the internal resistance and the external resistor.

We can calculate the current flowing in the circuit:

I = 24.0V / (1.0Ω + 5.0Ω) = 24.0V / 6.0Ω = 4.0A

Now, the terminal p.d. is the voltage drop across the external resistor. We can calculate it using Ohm's law:

V = I * R

Substituting the values:

V = 4.0A * 5.0Ω = 20.0V

Therefore, the terminal p.d. is 20.0V.

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The Tungsten filament lamp is a type of incandescent light source.

An incandescent light source works by using electricity to heat a filament inside the bulb until it becomes so hot that it emits light. In a tungsten filament lamp, the filament is made of tungsten, which is a metal that has a very high melting point. This allows the filament to get extremely hot without melting.

When an electric current passes through the filament, it heats up and starts to glow, producing visible light. The light emitted by a tungsten filament lamp is actually a result of the high temperature, which causes the atoms in the filament to vibrate and release energy in the form of light.

Incandescent light sources like tungsten filament lamps have been widely used for many years because they produce a warm, yellowish light that is similar to natural sunlight. However, they are not very energy-efficient, as a significant amount of the electrical energy is converted into heat rather than light.

In recent years, there has been a shift towards more energy-efficient alternatives like LED lamps and fluorescent lamps. LED lamps use a different mechanism to produce light, using a semiconductor that emits light when electric current passes through it. Fluorescent lamps use a gas-filled tube that emits ultraviolet light when electric current flows through it, and this ultraviolet light is then converted into visible light by a phosphor coating inside the tube.

So, in summary, the tungsten filament lamp is the type of incandescent light source among the options given. It works by heating a tungsten filament to a very high temperature, causing it to emit light. However, it is less energy-efficient compared to LED and fluorescent lamps.

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To calculate the relative humidity, we need to understand the concept of saturation and how much water vapor the air can hold at a given temperature.
Saturation is the point at which the air is holding the maximum amount of water vapor it can hold at a particular temperature. Once the air reaches saturation, any additional moisture will start to condense into liquid water.
The amount of water vapor that the air can hold increases with temperature. Warmer air can hold more water vapor, while cooler air can hold less.
Now, let's calculate the relative humidity using the given information:
1. Find the saturation vapor pressure at 40°C: - The saturation vapor pressure is the maximum amount of water vapor the air can hold at a specific temperature. - At 40°C, the saturation vapor pressure is approximately 55.3 mmHg.
2. Calculate the relative humidity: - Relative humidity is the ratio of the current partial pressure of water vapor to the saturation vapor pressure, expressed as a percentage. - Relative Humidity = (Partial pressure of water vapor / Saturation vapor pressure) * 100 - In this case, the partial pressure of water vapor is 38.8 mmHg and the saturation vapor pressure at 40°C is 55.3 mmHg. - Plugging in these values into the formula, we get: Relative Humidity = (38.8 mmHg / 55.3 mmHg) * 100 = 70.2%
Therefore, the relative humidity on this particular hot day is approximately 70%.
Answer: The correct option is 70.

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Detalhes da Resposta

The correct statement about the angle of dip at various points on Earth is: The angle of dip is zero at the equator and 90 degrees at the magnetic poles.
The angle of dip, also known as the inclination, refers to the angle between the Earth's magnetic field lines and the horizontal plane at a specific location. It tells us how much the magnetic field lines of the Earth are inclined or tilted at that point.
At the equator, the angle of dip is zero. This means that the magnetic field lines are parallel to the horizontal plane. As we move closer to the magnetic poles, the angle of dip increases. At the magnetic poles, the angle of dip is 90 degrees, indicating that the magnetic field lines are perpendicular to the horizontal plane.
The second statement that the angle of dip is greater at higher altitudes than at lower altitudes is incorrect. The angle of dip is primarily affected by the latitude or distance from the equator and the proximity to the magnetic poles, rather than the altitude. So, the angle of dip remains consistent at a specific latitude regardless of the altitude above sea level.
The third statement that the angle of dip is positive in the northern hemisphere and negative in the southern hemisphere is also incorrect. The angle of dip is positive in the northern hemisphere and negative in the southern hemisphere. This means that the magnetic field lines are inclined downwards in the northern hemisphere and upwards in the southern hemisphere.
The fourth statement that the angle of dip is constant at all points on Earth is incorrect as well. The angle of dip varies depending on the latitude and the proximity to the magnetic poles, as explained earlier. So, it is not constant across all points on Earth.
To summarize, the correct statement is that the angle of dip is zero at the equator and 90 degrees at the magnetic poles. It is important to note that the angle of dip is not affected by altitude but is primarily determined by latitude and proximity to the magnetic poles.

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As light ray enters a drop of water the light is refracted at the surface and at the end of the drop, it is totally internally reflected in which the reflected light returns to the front surface, where it again undergoes refraction as it moves from water to air. The result of this is a dispersed light of colours of different wavelengths.

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Detalhes da Resposta

To calculate the work done against gravitational force, we can use the formula:
Work = Force x Distance
In this case, the force we are working against is the gravitational force. The gravitational force is the force with which the Earth pulls objects towards its center. The formula for gravitational force is:
Force = Mass x Acceleration due to gravity
The mass of the object is given as 3.0 kg. The acceleration due to gravity on Earth is approximately 9.8 m/s^2.
Now, we need to find the distance the object is being carried, which is 240 m.
Plugging these values into the formulas, we have:
Force = 3.0 kg x 9.8 m/s^2 = 29.4 N
Work = 29.4 N x 240 m
Therefore, the work done against the gravitational force is equal to 29.4 N x 240 m = 7056 J = 7.1 kJ (rounded to one decimal place).
So, the correct answer is 7.2 kJ.

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Detalhes da Resposta

When a water droplet is placed on a freshly cut piece of wood, it spreads out to form a thin layer because the wood is adhesive to water.

Adhesion is the attraction between different substances, in this case, water and wood. Wood is a porous material, meaning it has tiny holes or gaps in its surface. These tiny holes create a large surface area for the water droplet to interact with.

When the water droplet comes into contact with the wood, the adhesive forces between the water molecules and the wood molecules are stronger than the cohesive forces between the water molecules. This causes the water droplet to spread out, trying to maximize its contact with the wood surface.

The spreading out of the water droplet forms a thin layer because the wood surface is not completely smooth. Instead, it has irregularities and imperfections, which allow the water to seep into those gaps and spread out further.

Therefore, when a water droplet is placed on a freshly cut piece of wood, it spreads out to form a thin layer due to the adhesive forces between the water and the wood surface.

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To find the tension in the rope, we can first use the formula for centripetal force, which is given by:
F_centripetal = (m * v^2) / r
where: - F_centripetal is the centripetal force - m is the mass of the object - v is the velocity of the object - r is the radius of the circular path
In this case, the mass of the object (m) is given as 2 kg and the radius (r) is given as 1.2 m.
Now, to find the velocity (v), we need to convert the given value of 120 rev/min to m/s.
Here's how we can do that:
1. First, convert the revolutions per minute (rev/min) to revolutions per second (rev/s) by dividing by 60 (since there are 60 seconds in a minute):
120 rev/min = 120/60 rev/s = 2 rev/s
2. Next, we need to convert the revolutions per second to the linear velocity in meters per second (m/s). To do this, we need to find the circumference of the circular path.
The circumference of a circle is given by the formula:
C = 2πr where r is the radius of the circular path.
Substituting the value of the radius (r = 1.2 m) into the formula, we have:
C = 2π * 1.2 = 2.4π Now, to find the linear velocity (v), we can multiply the circumference (C) by the number of revolutions per second (2 rev/s):
v = C * rev/s = 2.4π * 2 = 4.8π m/s
Now that we have the values of m (2 kg) and v (4.8π m/s), we can substitute them into the centripetal force formula to find the tension in the rope:
F_centripetal = (m * v^2) / r = (2 * (4.8π)^2) / 1.2
Simplifying further:
F_centripetal = (2 * 23.04π^2) / 1.2
F_centripetal = 38.4π^2
Finally, to get a numerical value for the tension in the rope, we can approximate the value of π to 3.14 and calculate the centripetal force:
F_centripetal ≈ 38.4 * 3.14^2 ≈ 379 N
Therefore, the tension in the rope is approximately 379 N.
Therefore, the correct answer is 379.

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The property of the wave shown in the diagram is diffraction.
Diffraction is the bending or spreading out of waves as they encounter an obstacle or pass through an opening. It occurs when waves encounter an obstacle that is comparable in size to their wavelength.
In the diagram, you can see that the wave is encountering an opening or a slit, and as a result, it is spreading out or bending around the edges of the opening. This bending or spreading out is characteristic of diffraction.
Diffraction is an important phenomenon in wave behavior and is observed in various situations, such as when sound waves pass through a doorway or when light waves pass through a narrow slit. It helps us understand how waves interact with obstacles and openings in their path.
In summary, the property of the wave shown in the diagram is diffraction, which is the bending or spreading out of waves as they encounter an obstacle or pass through an opening.

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Classical mechanics is a branch of physics that deals with the motion of macroscopic objects. It is based on the principles of Newton's laws of motion and is not considered to be part of elementary modern physics.

The other three options, quantum mechanics, special relativity, and nuclear physics, are all considered to be part of elementary modern physics because they deal with the behavior of matter and energy at the atomic and subatomic levels.

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Detalhes da Resposta

A pyrometer thermometer measures temperature from the thermal radiation emitted by objects.

When objects are heated, they emit thermal radiation, which is a form of electromagnetic radiation. This radiation is primarily in the infrared wavelength range. A pyrometer thermometer is specifically designed to measure the intensity of this thermal radiation and convert it into a temperature reading.

The pyrometer thermometer works based on the principle of measuring the amount of thermal radiation reaching the sensor. This is done using a detector that is sensitive to the infrared wavelength range. The detector absorbs the thermal radiation emitted by the object and generates an electrical signal proportional to the intensity of the radiation.

The electrical signal from the detector is then processed by the thermometer's electronics to calculate and display the corresponding temperature. The calibration of the thermometer ensures accurate temperature readings based on the known relationship between the intensity of thermal radiation and temperature.

Pyrometer thermometers are commonly used in industrial applications where contact-based temperature measurement methods are not feasible or accurate enough. They can measure temperatures of objects from a distance without physically touching them, which makes them suitable for measuring high temperatures, moving objects, or objects in hazardous or inaccessible environments.

Therefore, the pyrometer thermometer is the correct option for measuring temperature from thermal radiation emitted by objects.

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The name of the model of the atom that describes electrons as orbiting the nucleus in specific energy levels is the Bohr model.

The Bohr model was proposed by Danish physicist Niels Bohr in 1913. According to this model, electrons revolve around the nucleus in specific energy levels or shells. Each energy level corresponds to a certain amount of energy that an electron possesses. The energy levels are represented by whole numbers, with the closest energy level to the nucleus having the lowest energy and subsequent energy levels having higher energies.

Bohr's model also stated that electrons can only exist in certain fixed orbits around the nucleus. These orbits have a specific distance from the nucleus and are called stationary states. Electrons can move between these energy levels by absorbing or emitting energy in the form of photons.

The Bohr model successfully explained the observed emission and absorption spectra of atoms, as well as the stability of atoms. However, it has limitations in fully describing the behavior of electrons. It does not accurately represent the path or trajectory of electrons and does not account for other quantum effects.

Overall, the Bohr model provides a simplified and understandable framework for visualizing the arrangement of electrons in an atom, with electrons occupying specific energy levels or shells around the nucleus.

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To calculate the charge on each plate of a parallel plate capacitor, we can use the formula Q = CV, where Q is the charge, C is the capacitance, and V is the voltage applied. The capacitance of a parallel plate capacitor can be calculated using the formula C = εA/d, where C is the capacitance, ε is the permittivity of the medium (in this case, air), A is the area of each plate, and d is the distance between the plates. Given: Area of each plate (A) = 0.8 m^2 Distance between the plates (d) = 20 mm = 0.02 m Permittivity of air (ε) = 8.85 x 10^-12 F/m Using the formula for capacitance, we can calculate C: C = εA/d = (8.85 x 10^-12 F/m)(0.8 m^2)/(0.02 m) = 8.85 x 10^-12 F/m * 40 F = 3.54 x 10^-10 F Now, we can use the formula Q = CV to calculate the charge on each plate: Q = (3.54 x 10^-10 F)(120 V) = 4.25 x 10^-8 C = 42.5 x 10^-9 C = 42.5 nC Therefore, the charge on each plate of the parallel plate capacitor is **42.5 nC**.

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Detalhes da Resposta

The sensitivity of a thermometer refers to the smallest temperature change that it can detect or measure. In other words, it measures how fine or precise the thermometer is in detecting changes in temperature. A thermometer with high sensitivity is able to detect even small changes in temperature, while a thermometer with low sensitivity may only detect larger temperature fluctuations.

Therefore, in the given options, the statement "the smallest temperature change that can be detected or measured" accurately describes the sensitivity of a thermometer.

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The decay constant of a radioactive material represents the probability that an atom of the material will decay in a unit of time. In this case, we are given the half-life of the material which is the time it takes for half of the radioactive atoms to decay.
The relationship between the decay constant (λ) and the half-life (T½) is given by the formula:
λ = ln(2) / T½
where ln(2) is the natural logarithm of 2.
To find the decay constant, we can plug in the given half-life value into the formula. In this case, the half-life is 12 days.
λ = ln(2) / 12
Using a calculator, we can calculate the value of ln(2) ≈ 0.6931.
λ = 0.6931 / 12 ≈ 0.05775 day^(-1)
Therefore, the decay constant for this radioactive material is approximately 0.05775 day^(-1).
The correct answer is 0.05775 day^(-1).

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Detalhes da Resposta

Detalhes da Resposta

The polarities at X and Y would be north and north.

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A couple is a pair of forces that are equal in magnitude but opposite in direction, and that are applied to a body at different points. The forces of a couple do not produce any translation, but they do produce a rotation.

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In an AC circuit, resonance occurs when the impedance of the circuit is minimum.

Impedance is the total opposition to the flow of alternating current in a circuit, and it consists of two components: resistance (R) and reactance (X).

Reactance can be further divided into two types: inductive reactance (XL) and capacitive reactance (XC).

At resonance, the inductive reactance and the capacitive reactance are equal in magnitude and opposite in sign. This means that their effects cancel each other out, resulting in a minimum total reactance.

Since impedance is the combination of resistance and reactance, when the reactance is at its minimum, the impedance of the circuit is also at its minimum.

So, in summary, resonance occurs in an AC circuit when the impedance is minimum. At resonance, the inductive reactance and the capacitive reactance cancel each other out, resulting in a minimum total reactance and minimum impedance.

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Let's understand how a convex mirror forms images. In a convex mirror, the center of curvature and the focal point lie behind the mirror. Convex mirrors always produce virtual, upright, and diminished images.
Here, we are given that the object is placed 35 cm away from the convex mirror and the mirror has a focal length of 15 cm.
To find the location of the image, we can use the mirror formula, which states:
1/f = 1/v - 1/u
Where: - f is the focal length of the mirror, - v is the distance of the image from the mirror (negative for virtual image), - u is the distance of the object from the mirror (negative for real object in front of the mirror).
In this case, f = 15 cm and u = -35 cm (negative because the object is in front of the mirror).
Substituting these values into the formula, we get:
1/15 = 1/v - 1/-35
Simplifying the equation, we get:
1/v = 1/15 + 1/35
To add the fractions, we find the common denominator, which is 105. Then, we have:
1/v = (7 + 3)/105
1/v = 10/105
Simplifying further, we get:
1/v = 2/21
To solve for v, we take the reciprocal on both sides of the equation:
v = 21/2
Therefore, the location of the image is 10.5 cm behind the mirror.

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When light of a certain frequency is incident on a metal surface, no photoelectrons are emitted. This is because the energy of the photons in the light is not enough to overcome the work function of the metal, which is the minimum amount of energy required to remove an electron from the metal surface.
If the frequency of the light is increased, it means that the energy of the photons increases. This increase in energy means that there is now enough energy to overcome the work function of the metal. As a result, photoelectrons are now emitted from the metal surface.
Now, let's consider the stopping potential. The stopping potential is the minimum potential difference that needs to be applied across a pair of electrodes in order to stop the flow of photoelectrons from reaching the other electrode.
When the frequency of the light is increased, the energy of the photons also increases. This means that the photoelectrons have more kinetic energy when they are emitted from the metal surface. As a result, a higher stopping potential is required to stop the more energetic photoelectrons from reaching the other electrode.
Therefore, the stopping potential increases when the frequency of the light is increased.

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Detalhes da Resposta

The branch of physics that deals with the motion of objects and the forces acting on them is called mechanics.

Mechanics is the foundation of physics that studies how objects move and interact under the influence of forces. It encompasses both the study of the motion of macroscopic objects, such as cars and planets, and the behavior of microscopic particles, such as atoms and molecules.

Mechanics is divided into two main branches:

• Classical mechanics: This branch deals with the motion of objects that are larger than atoms and are not moving near the speed of light. It includes the well-known laws of motion formulated by Sir Isaac Newton, such as Newton's laws of motion, which describe how the velocity and acceleration of an object are related to the forces acting upon it.
• Quantum mechanics: This branch deals with the behavior of particles at the atomic and subatomic levels. It is based on probabilities and wave-particle duality, rather than classical concepts of motion and force. Quantum mechanics is essential for our understanding of the behavior of electrons, photons, and other quantum particles.

Therefore, when referring to the branch of physics that specifically focuses on the motion of objects and the forces acting on them, the correct answer is mechanics.