KinematicsHard
Question
A wooden block of mass 10 gram is dropped from the top of a tower of height 100 m. Simultaneausly a bullet of mass 10 g is fired from the foot of the tower vertically upwards with a velocity of 100 m/s. If the bullet is embedded in it, how high will the block rise above the tower before it starts falling? (g = 10 m/s2) :-
Options
A.75 m
B.85 m
C.80 m
D.10 m
Solution
The bullet and block will meet after time,
t =
= 1sec.
distance travelled by block during this time
S -
gt2 = 5m
distance travelled by bullet,
100 - 5 = 95 m
Velocity of bullet before collision
⇒ v1 = u - gt
= 100 - 10 × 1 = 90 m/sec
Velocity of block before collision
⇒ v2 = gt = 10 m/sec
m1v1 + m2v2 = (m1+ m2)v
⇒ v =
= 40m / sec
max. height reached by block =
= 80 m
from the top of tower = 80 - 5 = 75 m
t =
distance travelled by block during this time
S -
distance travelled by bullet,
100 - 5 = 95 m
Velocity of bullet before collision
⇒ v1 = u - gt
= 100 - 10 × 1 = 90 m/sec
Velocity of block before collision
⇒ v2 = gt = 10 m/sec
m1v1 + m2v2 = (m1+ m2)v
⇒ v =
max. height reached by block =
from the top of tower = 80 - 5 = 75 m
Create a free account to view solution
View Solution FreeMore Kinematics Questions
A ball is thrown vertically upward with speed 10 m/sec and it returns to ground withspeed of 8 m/sec. There exists a con...A particle starts moving from time $t = 0$ and its coordinate is given as $x(t) = 4t^{3} - 3t$.A. The particle returns t...A small ball rolls of the top of a stairway horizontally with a velocity of 4.5 m s-1. Each step is 0.2 m high and 0.3 m...A particle is thrown vertically upward. Its velocity at half of the height is 10 m/s, then the maximum height attained b...There are two values of time for which a projectile is at the same height. The sum of these two times is equal to (T = t...