Question

1.) A 1.7-kg falcon catches and holds onto a 0.675-kg dove from behind in midair. What is their final speed, in meters per second, after impact if the falcon’s speed is initially 27 m/s and the dove’s speed is 7.5 m/s in the same direction?

2.) a.) A bowling ball of mass m_b = 3.7 kg is rolled down the lane with a velocity of v₁ = 2.8 m/s. It strikes a single remaining pin m_p = 0.92 kg head on. After the collision the bowling ball has a velocity (in the same direction) of v₂ = 1.65 m/s. Write an expression for the velocity of pin in the horizontal direction after the impact, v_p.
b.) What is the pins speed in m/s?
c.) Assuming the coefficient of friction is μ_k = 0.1, how far in meters could the pin slide before stopping if it doesn't topple?

3.) A runaway train car that has a mass of 14500 kg travels at a speed of 5.8 m/s down a track.
Randomized Variables: m = 14500 kg, v = 5.8 m/s, F = 1250 N
Part (a) What is the time required for a force F to bring the car to rest, expressed in terms of m, v, and F?
Part (b) Compute this time, in seconds, for a force of 1250 N.

4.) A person slaps her leg with her hand, bringing her hand to rest in 265 ms from an initial speed of 3.85 m/s. What is the magnitude of the average force exerted on the leg, in newtons, taking the effective mass of the hand and forearm to be 1.7 kg?

Answer 1

con m S. ME 1.7kg and initial velocity dri= 27. m/s Dove mass, mp=0.675 kg and intercity ; 7.5 m/s Now, from momentum conservation, we get, mp Of it mo voi = (MF + m) [w, the ] L required velocity 5 v- MEVEitm ME VFi tmoupi met mo 1 v = 74x27 + 0-675x7.5 1.7 +0.675 - v = 21.46 m/s.