Question

b) Two objects of masses 50g and 100g are moving along the same line and direction with
velocities of 5m/s and 10 m/s respectively. They collide and after the collision, the second
object moves at a velocity of 8 m/s. Determine the velocity of the first object?​

Answer 1

Answer:

velocity of first object is 9m/s.

Explanation:

mass 1= 50g

mass 2=100g

Initial velocity 1=5m/s

Initial velocity 2=10m/s

Final velocity 1=?

Final velocity 2=8m/s

now take momentum of the objects

p=mv (initial momentum)

50*5+100*10=1250gm/s-------------1

p=mv (final momentum)

50*v+

100*8=(50v+800)m/s------------2

Now combine 1 and 2-----

1250gm/s=50v+800m/s

1250-800=50v

450=50v

50v=450

v=450/50

v=9m/s.

Therefore velocity of the first object is 9m/s.

Answer 2

Explanation:

Given: M1= 50 g

U1 = 5 m/s

M2 = 100 g

U2 = 10 m/s

V1 = ?

V2 = 8 m/s

from law of conservation of momentum

m1u1 + m2u2 = m1v1 + m2v2

after putting values in it we determined that

v1 = 17 m/ s