Understanding Elastic and Inelastic Collisions

The law of conservation of momentum states that, 

• p before is less than p after
• p before is the same as p after
• p before is more than p after

Tags

NGSS.HS-PS2-2

A 2.5 kg ball moving at 4.2 m/s collides with a 2.5 kg stationary ball. If the first ball is at rest after the collision, what is the velocity of the second ball? 

• 2.1 m/s
• 2.5 m/s
• 4.2 m/s
• 8.4 m/s

Tags

NGSS.HS-PS2-2

A 3,000 kg truck moving at +10 m/s hits a 1,000 kg parked car which moves off at +15 m/s. What is the velocity of the truck?

• 10 m/s
• 0 m/s
• 5 m/s
• 2 m/s

Tags

NGSS.HS-PS2-2

While playing pool, the white cue ball strikes the 8 ball. Before the collision, the cue ball's velocity was 10 m/s and the 8 ball was at rest. If both ball's have a mass of 0.15 kg and the cue ball's velocity after the collision is 2 m/s, what is the 8 ball's velocity?

• 2 m/s
• 8 m/s
• -2 m/s
• 1.5 m/s

Tags

NGSS.HS-PS2-2

What makes it possible to determine the motion of objects before or after colliding?

• Conservation of Energy
• Conservation of Strength
• Conservation of Momentum
• Conservation of Homework

Tags

NGSS.HS-PS2-2

Collisions can be ____________or ___________.

• fast or slow
• far or near
• elastic or inelastic
• none of the above

The total momentum before a collision is _________ the total momentum after a collision. (conservation of momentum)

• equal to 
• less than 
• more than
• It depends on the type of collision

Tags

NGSS.HS-PS2-2

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

Tags

NGSS.HS-PS2-2

A dart with a mass of 0.5kg is thrown at 15m/s and sticks into a 1kg apple hanging on a string.  What is the velocity of the dart and apple just after the dart is embedded? 

• 0 m/s
• 5 m/s
• 10 m/s
• 15 m/s

Tags

NGSS.HS-PS2-1

NGSS.HS-PS2-2

When is momentum conserved in a collision?

• When the collision is inelastic.
• When the collision is elastic.
• When the collision is inelastic OR elastic but never an explosion.
• All collisions.

Tags

NGSS.HS-PS2-2