In an automobile collision, how does an airbag lessen the blow to the passenger? Assume as a result of the collision, the passenger stops. * 5 The air bag decreases the momentum change of the passenger in the collision. During the collision, the force from the air bag is greater than would be the force from the windshield or dashboard so the passenger cannot hit the hard objects. The stopping impulse is the same for either the hard objects or the airbag. Unlike the windshield or dashboard, the air bag increases the time for the slowing process and thus decreasing the average force on the passenger. The airbag is there to insure the seatbelt holds.

About  ELASTIC collisions: (both questions are related to each other.) Please answer it short and easy to understand What happens if the cars have the same mass but one car has twice the velocity?  If one car has twice the mass as the second car, can you still get the cars to bounce back equally?  Explain how.

I am unsure how to do this problem with out the final velocity of the second object.

Conservation of Momentum 1. Refer to figure 1. The orange cart (m₁) collides with the red cart (m₂). Calculate the red cart's final velocity after impact. Prior to impact m₁ m₂ m₁ = 10.0 kg V₁ = 10.0 m/s Figure 1 m₂ = 5.00 kg V₂ = 5.00 m/s m₁ Post impact m₁ = 10.0 kg V₁ = 8.00 m/s m₂ m₂ = 5.00 kg V₂ = ?

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I.  A lump of clay (m = 3.01 kg) is thrown towards a wall at speed v = 3.15 m/s.  The lump sticks to the wall.  (a) What kind of collision is it?  Is momentum conserved during this collision?  Why or why not? (b) Calculate the impulse imparted on the lump by the wall. (c) Calculate percent of initial kinetic energy lost during this collision.   II.  Same lump is thrown towards the same wall, but this time it bounces off the wall at speed of 3.15 m/s. (a) What kind of collision is it?  Is momentum conserved during this collision?  Why or why not? (b) Calculate the impulse imparted on the lump by the wall. (c) Calculate percent of initial kinetic energy lost during this collision.   III.  Same lump is thrown towards the same wall, but this time it bounces off the wall at speed of 2.24 m/s. (a) What kind of collision is it?  Is momentum conserved during this collision?  Why or why not? (b) Calculate the impulse imparted on the lump by the wall. (c) Calculate percent of initial kinetic…

For each of these collisions, can we see that momentum is conserved? Show why or why not, based on your data.

2. Conservation of Linear Momentum See Figure 2. Block 1 of mass m₁ slides from rest along a frictionless ramp from an unknown heighth and then collides with stationary block 2, which has mass m₂ = 3m₁ . The collision is an elastic one. After the collision, block 2 slides into a friction-filled region where the coefficient of kinetic friction is 0.5 and comes to a stop through a distance d = 10 m in that region. (a) What is the height h? (ANSWER: h = 20 m) (b) What is the velocity of block 1 just after the collision? (ANSWER: (-)10 m/s) (If the collision were instead, completely inelastic (that is, the objects stick together, what is the height h?)