Laws Of Motion Question 199
Question: A rocket has an initial mass of $ 20\times 10^{3}kg $ . If it is to blast off with an initial acceleration of $ 4m{{s}^{-2}} $ , the initial thrust needed is $ (g\tilde{=}10m{{s}^{-2}}) $ [Kurukshetra CEE 1996]
Options:
A)$ 6\times 10^{4}N $
B) $ 28\times 10^{4}N $
C) $ 20\times 10^{4}N $
D) $ 12\times 10^{4}N $
Show Answer
Answer:
Correct Answer: B
Solution:
$ F=m(g+a)=20\times 10^{3}\times (10+4)=28\times 10^{4}N $
