Work Energy And Power Question 196
Question: A car of mass 1000 kg accelerates uniformly from rest to a velocity of 54 km/hour in 5s. The average power of the engine during this period in watts is (neglect friction) [Kerala PET 2002]
Options:
A) 2000 W
B) 22500 W
C) 5000 W
D) 2250 W
Show Answer
Answer:
Correct Answer: B
Solution:
Power $ =\frac{\text{Work done}}{time}=\frac{\text{Increase in K}\text{.E}\text{.}}{time} $
$ P=\frac{\frac{1}{2}mv^{2}}{t}=\frac{\frac{1}{2}\times 10^{3}\times {{(15)}^{2}}}{5}=22500W $
