Work Energy And Power Question 269
Question: A force applied by an engine of a train of mass $ 2.05\times 10^{6} kg $ changes its velocity from 5m/s to 25 m/s in 5 minutes. The power of the engine is
Options:
A) 1.025 MW
B) 2.05 MW
C) 5 MW
D) 6 MW
Show Answer
Answer:
Correct Answer: D
Solution:
[d] $ Power=\frac{Work done}{Time}=\frac{\frac{1}{2}m( v^{2}-u^{2} )}{t} $
$ P=\frac{1}{2}\times \frac{2.05\times 10^{6}\times [ {{( 25 )}^{2}}-( 5^{2} ) ]}{5\times 60} $
$ P = 2.05\times 10^{6}W= 2.05 MW $