Question

If glider #2 is at rest and located halfway in between the photogates. What will the resultant motion be if glider #1 is moving to the right with a speed of 0.5 m/sec and they stick together when they collide?

Answer 1

glider #2 is at rest and located halfway in between the photogates.

Elasticity of collisions may be defined as,

e = (v_2f - v_1f) / (v_1i - v_2i)

where, v₁ and v₂ = velocity of glider 1 & 2

Using conservation of momentum,

m₁ v_1i + m₂ v_2i = m₁ v_1f + m₂ v_2f

where, v_1i and v_2i = initial velocity of the glider 1 & 2

v_1f and v_2f = final velocity of the glider 1 & 2

For an elatis collison between the two gliders, we have

(1/2) m₁ v_1i² + (1/2) m₂ v_2i² = (1/2) m₁ v_1f² + (1/2) m₂ v_2f²

The initial momentum of the sytem which will be given as :

p_initial = m₁ v_i               

The final momentum of the sytem which will be given as :

p_final = (m₁ + m₂) v_f

Conservation of momentum comes from the given equation :

F_external . t = [m₁ v_1i + m₂ v_2i]