Question

A bulb rated 60 W operates for 2 hours. How much energy does it consume in this time?

• A. 120 J
• B. 1200 J
• C. 720 J
• D. 4320 J

Hint:

Remember: Energy consumed is calculated as power multiplied by time. Make sure to convert time into seconds if given in hours.

Answer 1

The Correct Option is B

Step 1: Use the formula for energy consumption The energy consumed by an electrical device is given by the formula: \[ E = P \times t \] where: - \( E \) is the energy consumed (in joules), - \( P \) is the power of the device (in watts), - \( t \) is the time for which the device operates (in seconds). Step 2: Convert time to seconds Given: - Power \( P = 60 \, \text{W} \), - Time \( t = 2 \, \text{hours} = 2 \times 3600 = 7200 \, \text{seconds} \). Substitute these values into the formula: \[ E = 60 \times 7200 = 432000 \, \text{J} \] Answer: Therefore, the energy consumed by the bulb is 432000 J. So, the correct answer is option (4).