1. Lucky Larry was in a car crash. He hit a brick wall going 40 mph. But his airbag inflated and saved him because
A. it reduced the time of the collision.
B. it reduced his initial velocity.
C. it reduced his change in momentum.
D. it reduced his average
force.

Ablock having mass m slides down an inclined plane. the force of friction between the block and the inclined plane is f, the block's weight is m g, and the normal force is n. (a) draw a free – body force diagram showing the forces acting on the block. (b) write down all relevant newton’s equations for a given situation.