pl answer Q 20 OBJECT
19. A body of mass 6Kg makes an elastic collision with another body which is at rest. The first body
then moves in the same direction with its speed reduced by one half. Then the mass of the second
20. They are small elastic balls placed at rest on a smooth horizontal surface which are circulated at the
. Find the least velocity Which
21.
22.
23.
24.
25,
extremes with radius 2m. The masses of balls are M' 7' 22
should be provided to the first ball of mass m such that 5th ball completes a vertical circle (nearly)
[in ms-ll•
Two balls A and B of masses 0.10 kg and 0.25kg respectively are connected by a stretched spring.
The system is placed on a smooth table. The initial acceleration of ball B is 2m/s2 westward when
system is released. Find the magnitude and direction of acceleration of ball A (in m/s2) in
eastward.
A ball is projected from a point in a horizontal plane so as to strike a vertical wall at right angle. The
ball after striking the horizontal plane returns to the point of projection. The coefficient of restituticm
for the two collisions, assuming same for both collisions is K x 1/4. Determine the value of K
A body of mass 2M in motion undergoes one dimensional semi elastic collision With a stationary
body of mass 3M. If the final kinetic energy of the system is 7/16 times the initial K.E of the
system, then l/e is equal to (e is the coefficient of restitution for the concerned collision)
A sphere of mass 2Kg strikes another sphere of mass 3Kg at rest with a velocity Of 5ms-l. If they
m/sec
move together after collision, then the common velocity is
Two particles of equal masses 4M are initially at rest. A particle of mass M moving at speed u
collides elastically with one of the larger balls. How many collisions Occur ?
4M
KEY SHEET
I)BC 3)ACD
5) BCD 6)AD 7)AC 8)ABCD
10)C
II)A 12)C 13)B 14)A
16) B-R; c-P; D-PQRS
19)2
20) 3
21)5
22) 2
23) 4
24) 2
25) 2
LECTURE SHEET - 2
(Collision in Two dimensions, Recoil of gun, Rocket propulsion)
Section -A
1. A small particle travelling with a velocity v collides elastically With a spherical body of equal
and radius r initially kept at rest. The centre of this spherical body is located a distance r)
A) particle stops and spherical body move in the direction of particle
B) both particle and spherical body move perpendicular to each other
C) velocity of particle after collision is —
D) velocity of the spherical body after collision Is r —