Electric Power

Given: The power of the bulb is

60%20%5C%2C%20%5Ctext%7BW%7D

, and the time of operation is

2%20%5C%2C%20%5Ctext%7Bhours%7D

. Step 1: Convert time to seconds Since

1%20%5C%2C%20%5Ctext%7Bhour%7D%20%3D%203600%20%5C%2C%20%5Ctext%7Bseconds%7D

, the total time is:

t%20%3D%202%20%5Ctimes%203600%20%3D%207200%20%5C%2C%20%5Ctext%7Bseconds%7D

Step 2: Formula for energy Energy is given by the formula:

E%20%3D%20P%20%5Ctimes%20t

where: -

P

is the power in watts, -

t

is the time in seconds. Step 3: Substitute the values Substitute the given values into the formula:

E%20%3D%2060%20%5Ctimes%207200%20%3D%20432000%20%5C%2C%20%5Ctext%7BJ%7D%20%3D%204320%20%5C%2C%20%5Ctext%7BkJ%7D

Answer: The correct answer is option (4): 4320 J.

Chapter Questions
2 MCQs