WAEC SSCE - Physics - 2009 (Objective)

Question 1 Report

An ammeter connected to an a.c circuit records 5.5. The peak current in the circuit is

7.8A

7.1A

3.8A

3.5A

Answer Details

In an AC circuit, the current is constantly changing direction and amplitude, and we use the root mean square (rms) value to measure the effective current flowing in the circuit. The peak value is the maximum value the current can reach, and it is equal to the square root of 2 times the rms value. So, in this case, we can use the formula: Peak value = sqrt(2) x rms value Given that the ammeter records 5.5, which is the rms value, we can calculate the peak value as follows: Peak value = sqrt(2) x 5.5 Peak value = 7.77 Rounded to one decimal place, the answer is 7.8A. Therefore, option A is the correct answer.






Press & Hold to Drag Around
Click Here to Close