Question

How much time is needed for a 15,000 W engine to do 1,800,000 J of work? (Power: P = W/t)

0.008 s
8 s
120 s
1,785,000 s

Answer 1

To find the time needed for the engine to do 1,800,000 joules of work with a power of 15,000 watts, we can use the formula for power:

\[
P = \frac{W}{t}
\]

where:
- \( P \) is power in watts (W),
- \( W \) is work in joules (J),
- \( t \) is time in seconds (s).

Rearranging the formula to solve for time, we have:

\[
t = \frac{W}{P}
\]

Now, substituting in the values provided:

\[
t = \frac{1,800,000 \, \text{J}}{15,000 \, \text{W}}
\]

Calculating this gives:

\[
t = 120 \, \text{s}
\]

So, the time needed for the engine to do 1,800,000 J of work is **120 seconds**.