Question

Find the energy in joules consumed in 10 hours by four devices of power 500 W each.

Answer 1

Given: 

Power of each device, \( P = 500 \, \text{W} \)
Number of devices, \( n = 4 \)
Time, \( t = 10 \, \text{hours} = 10 \times 3600 = 36000 \, \text{s} \)

Step 1: Total power

\[ P_{\text{total}} = n \times P = 4 \times 500 = 2000 \, \text{W} \]

Step 2: Energy consumed

Energy, \( E = P_{\text{total}} \times t \)
\[ E = 2000 \times 36000 = 7.2 \times 10^7 \, \text{J} \]

Answer:

The total energy consumed by the four devices in 10 hours = 7.2 × 10⁷ J