Work Energy And Power Question 191
Question: A car of mass 1250 kg is moving at 30m/s. Its engine delivers 30 kW while resistive force due to surface is 750N. What max acceleration can be given in the car [RPET 2000]
Options:
A) $ \frac{1}{3}m/s^{2} $
B) $ \frac{1}{4}m/s^{2} $
C) $ \frac{1}{5}m/s^{2} $
D) $ \frac{1}{6}m/s^{2} $
Show Answer
Answer:
Correct Answer: C
Solution:
Force produced by the engine
$ F=\frac{P}{v}=\frac{30\times 10^{3}}{30} $ =103N
Acceleration= $ \frac{\text{Forward force by engine–resistive force}}{\text{mass of car}} $
$ =\frac{1000-750}{1250}=\frac{250}{1250} $ = $ \frac{1}{5}m/s^{2} $
