Question

suppose we have two masses m1=2000 g and m2=4000g, where m1 is moving with initial velocity v1,i=24m/s and m2 is at rest at t=0s. they collide with each other at some time t=t1 after the collision they stick together and move as one. what is the final velocity, v1f, (magnitude and direction)

Answer 1

Answer:

The final velocity is 8 m/s and its direction is along the positive x-axis

Explanation:

Given :

Mass, m₁ = 2000 g = 2 kg

Mass, m₂ = 4000 g = 4 kg

Initial velocity of mass m₁, v₁ = 24i m/s

Initial velocity of mass m₂, v₂ = 0

According to the problem, after collision the two masses are stick together and moving with same velocity, that is, $v_{1f}$.

Applying conservation of momentum,

Momentum before collision = Momentum after collision

$m_{1} v_{1} +m_{2} v_{2} =(m_{1}+m_{2}) v_{1f}$

Substitute the suitable values in the above equation.

$2\times24 +4\times0 =(2+4}) v_{1f}$

$v_{1f}=8i\ m/s$