Kinematics Question 227
Question: A man throws a ball vertically upward and it rises through 20 m and returns to his hands. What was the initial velocity $ (u) $ of the ball and for how much time $ (T) $ it remained in the air $ [g=10m/s^{2}] $ [MP PET 2001]
Options:
A) u = 10 m/s, T = 2s
B) u = 10 m/s, T = 4s
C) u = 20 m/s, T = 2s
D) u = 20 m/s, T = 4s
Show Answer
Answer:
Correct Answer: D
Solution:
$ u=\sqrt{2gh}=\sqrt{2\times 10\times 20}=20\ m/s $
and $ T=\frac{2u}{g}=\frac{2\times 20}{10}=4 $ sec
