Inelastic Collisions

Two football players with mass 75 kg and 100 kg run directly toward each other with speeds of -6 m/s and 8 m/s respectively. If they grab each other as they collide, the combined speed of the two players just after the collision would be:

• 2 m/s 

• 3.4 m/s 

• 4.6 m/s 

• 7.1 m/s

A large box slides across a frictionless surface with a velocity of 12 m/s and a mass of 4 kg,  collides with a smaller box with a mass of 2 kg that is stationary.  The boxes stick together. What is the velocity of the two combined masses after collision?

• 0 m/s
• 4 m/s
• 8 m/s
• 12 m/s

Joe is trying to tackle Carson while Carson is standing still. Joe is running at 15 m/s and has a mass of 32 kg. Carson has a mass of 64 kg. What is their final velocity, assuming this is a perfectly inelastic collision? (do not write units)

• 5

• 10

• 5.5

• 12.4

What is the the total momentum of the red and blue ball before the collision?

• 16 kg m/s
• 32 kg m/s
• 2 kg m/s
• 6 kg m/s

The momentum before objects collide is always written as:

Tags

112.45.c.7.E

The momentum after objects collide in a perfectly inelastic collision is written as:

Tags

112.45.c.7.E

In a physics experiment, two carts of mass 1.5 kg each are rolled towards each other.  The orange cart has a velocity of 2 m/s and the blue cart has a velocity of -1m/s.  The carts stick together when they collide.  Calculate their final speed.

• 0.5 m/s
• 1.0 m/s
• 0.33 m/s
• 0.67 m/s

A 9 kg blob moving at 5 m/s collides and sticks to a second blob with a mass of 5 kg. If the two blobs stick together, what will the velocity of the two blobs move at?

• 3.57 m/s

• 3.2 m/s

• 10.0 m/s

• 9.0 m/s

A 2000 kg car moves to the right with a speed of 30 m/s and collides with a 400 kg truck that is stationary. If this is an inelastic collision, what is the velocity of the car and truck after collision?

• 150 m/s

• 25 m/s

• 60,000 m/s

• 12,000 m/s

A 1.5 kg ball moves to the right with a velocity of 4 m/s and collides with a 2 kg ball that is stationary. If this is a perfectly elastic collision, what is the velocity of the 2 kg ball after the collision?

• 1.7 m/s

• 3 m/s

• 4 m/s

• 3.5 m/s