Two skaters collide and grab onto each other on frictionless ice. One of them (mass = 70.0 kg) is moving to the right at 4.00 m/s, while the other (mass = 65.0 kg) is moving to the left at 2.50 m/s. What are the magnitude and direction of the velocity of these skaters just after they collide?

The Two skaters collide and grab onto each moving to the right with a velocity of 0.87 m/s.

m₁ = 70 kg, m₂ = 65 kg, u₁ = velocity of first skater before collision = 4 m/s, u₂ = velocity of second skater before collision = - 2.5 m/s (left), v is the velocity of the skaters after they collide.

Total momentum before collision = Total momentum after collision

m₁u₁ + m₂u₂ = (m₁ + m₂)v

70(4) + 65(-2.5) = (70 + 65)v

135v = 280 - 162.5

135v = 117.5

v = 0.87 m/s

The Two skaters collide and grab onto each moving to the right with a velocity of 0.87 m/s.

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