Question

A 0.32−kg puck at rest on a horizontal frictionless surface is struck by a 0.22−kg puck moving in the positive x-direction with a speed of 8.8 m/s. After the collision, the 0.22−kg puck has a speed of 1.7 m/s at an angle of θ=60

counterclockwise from the positive x-axis. (a) Determine the velocity of the 0.32−kg puck after the collision. magnitude m/s direction - (clockwise from the +x-axis) (b) Find the percent of kinetic energy lost in the collision. 100 ∣ KE ∣ / ∣ ΔKEᵢ ∣ =

Answer 1

The velocity of the 0.32-kg puck after the collision is determined using the conservation of momentum, and the percent of kinetic energy lost is calculated by comparing the initial and final kinetic energies of the system.

Step-by-step explanation:

The student is asking about the results of a two-dimensional inelastic collision between two hockey pucks on a frictionless surface. Using the conservation of momentum, the final velocity of the 0.32-kg puck can be found. To find the percent of kinetic energy lost, we would compare the initial and final kinetic energies of the system.

Part (a): Velocity of the 0.32-kg Puck After Collision

To calculate the velocity of the 0.32-kg puck after the collision, we must use the principle of conservation of momentum because the collision is inelastic. The total momentum before the collision must equal the total momentum after the collision. We use the given speed and angle of the 0.22-kg puck to find the velocity components of both pucks after the collision.

Part (b): Percent of Kinetic Energy Lost

The kinetic energy of the system is not conserved in an inelastic collision. To find the percent of kinetic energy lost, we calculate the kinetic energies before and after the collision and then compare them to find the difference, which gives us the kinetic energy lost during the collision. The calculation can be done using the kinetic energy formula (KE = 1/2 mv^2) and the results from part (a).