Kinematics Question 235
Question: A body falling from a high Minaret travels 40 meters in the last 2 seconds of it’s fall to ground. Height of Minaret in meters it’s (take $ g=10m/s^{2} $ ) [MP PMT 2002]
Options:
A) 60
B) 45
C) 80
D) 50
Show Answer
Answer:
Correct Answer: B
Solution:
Let height of minaret it’s H and body take time T to fall from top to bottom.
$ H=\frac{1}{2}gT^{2} $ -(i)
In last 2 sec. body travels distance of 40meter so in $ (T-2) $ sec distance travelled $ =(H-40)\ m $ . $ (H-40)=\frac{1}{2}g{{(T-2)}^{2}} $ -(ii)
By solving (i) and (ii) $ T=3 $ sec and $ H=45\ m $ .