Ram is standing on the edge of a cliff 30 m high. He throws ball vertically up with a velocity of 10 m/s at (time) $t = 0$ . The ball strikes the ground after the flight and does not rebound. Match the time intervals in column-I with description of motion in column-II.

Open in App

Solution

$A n s . : A \to 1, B \to 2, C \to 4, D \to 5$
$V^{2} = u^{2} - 2 g h$
$H = \frac{(10)^{2}}{(2 * 10)} = 5.0$ m ;
$T = \frac{u}{g} = \frac{10}{10} = 1.0$ sec ;
Ball is moving up upto 1 sec
$A \to 1$
Now, ball has reached the highest height with initial velocity u=0m/sec ;
For retuning it back to initial position i.e at height of 30 m ;
Distance covered back = 5 m ;
$H = u t + \frac{1}{2} g t^{2} = \frac{1}{2} (10 \times t^{2}) = 5$
$T = 1 s e c \Rightarrow 2 s e c i n t o t a l$
Speed of ball is increasing with final speed $= g t = 10 \times 1 = 10 m / s e c$
$B \to 2 a n d D \to 5$
After this initial velocity $= 5$ m/sec
Final velocity $= 0$ m/s as it does not rebound ;
Distance covered $= 30$ m ;
So, $h = 5 t + \frac{1}{2} 10 t^{2} = 30$
$T = 2 s e c \Rightarrow 4 s e c$ in total from initial position.;
$C \to 4$

Suggest Corrections

Similar questions

Q. Ram is standing on the edge of a cliff

30 m

. He throws ball vertically up with a velocity of

10 m / s

at (time)

t = 0

. The ball strikes the ground after the flight and does not rebound. Match the time intervals in column-I with description of motion in column-II

Q. A man is standing on top of a building

100 m

high. He throws two balls vertically, one at

t = 0

and other after a time interval less than

2

seconds. The later ball is thrown at a velocity of half the first. The vertical gap is found to remain constant. Calculate the velocity with which the balls were thrown(in m/s).

A boy is standing on the edge of the roof at a height 78.4 m. He throws a ball vertically upwards with velocity 19.6 m/s. After how much time (in s) the ball will reach the ground? (Take a = 9.8 $m / s^{2}$ downwards)

Q. A man is standing on top of a building 100 m high. He throws two balls vertically, one at t = 0 and other after a time interval (less than 2 s). The later ball is thrown at a velocity of half the first. The vertical gap between first and second ball is 15 m at t = 2 s. The gap is found to remain constant. The velocities with which the balls were thrown are (Take g = 10 m

s^{- 2}

A boy is standing on the edge of the roof at height of $78.4 m$ . He throws a ball vertically upwards with velocity of $19.6 m s^{- 1}$ . After how much time the ball will reach the ground? (Take $g = 9.8 m s^{- 2}$ )

Join BYJU'S Learning Program

Ram is standing on the edge of a cliff 30 m high. He throws ball vertically up with a velocity of 10 m/s at (time) t=0. The ball strikes the ground after the flight and does not rebound. Match the time intervals in column-I with description of motion in column-II.

Ram is standing on the edge of a cliff 30 m high. He throws ball vertically up with a velocity of 10 m/s at (time) $t = 0$ . The ball strikes the ground after the flight and does not rebound. Match the time intervals in column-I with description of motion in column-II.