Work Energy And Power Question 194
Question: A 60 kg man runs up a staircase in 12 seconds while a 50 kg man runs up the same staircase in 11, seconds, the ratio of the rate of doing their work is [AMU (Engg.) 2001]
Options:
A) 6 : 5
B) 12 : 11
C) 11 : 10
D) 10 : 11
Show Answer
Answer:
Correct Answer: C
Solution:
$ P=\frac{mgh}{t} $
therefore $ \frac{P_1}{P_2}=\frac{m_1}{m_2}\times \frac{t_2}{t_1} $ (As h = constant) \ $ \frac{P_1}{P_2}=\frac{60}{50}\times \frac{11}{12}=\frac{11}{10} $