Kinematics Question 214
Question: A stone is thrown with an initial speed of 4.9 m/s from a bridge in vertically upward direction. It falls down in water after 2 sec. The height of the bridge it’s [AFMC 1999; Pb. PMT 2003]
Options:
A) 4.9 m
B) 9.8 m
C) 19.8 m
D) 24.7 m
Show Answer
Answer:
Correct Answer: B
Solution:
Speed of stone in a vertically upward direction is 4.9 m/s. So for vertical downward motion we will consider $ u=-4.9\ m/s $
$ h=ut+\frac{1}{2}gt^{2}=-4.9\times 2+\frac{1}{2}\times 9.8\times {{(2)}^{2}} $
$ =9.8\ m $