Impulse 4 - What have we learned?

Airbags in cars work by gradually decreasing the momentum of humans inside cars during collisions. How do they work?

• Decreasing the distance over which the force acts

• Increasing the length of time the force acts

• Decreasing the mass of the driver

• Increasing the rate of acceleration of the driver

How would you find the impulse using this graph?

• Slope

• Inverse of Slope

• Area

• Linearize, the take slope

A woman runs off of a (short, close to the ground) ledge with velocity 'v' and jumps onto a stationary skateboard. The skateboard begins to roll while she stands on it. How does the final velocity of the woman on the skateboard compare to her initial velocity while running?

• She goes faster once she jumps onto the skateboard

• She goes slower once she jumps onto the skateboard

• She goes the same velocity once she jumps onto the skateboard

• It's impossible to know without knowing their relative masses

What is impulse?

• Momentum

• Inertia

• A change in momentum

• A change in inertia