Question

If a car stops suddenly, you feel "thrown forward." We’d like to understand what happens to the passengers as a car stops. Imagine yourself sitting on a very slippery bench inside a car. This bench has no friction, no seat back, and there’s nothing for you to hold onto.(a) identify all of the forces action on you as thecar travels at a perfectly steady speed on level ground.(b) repeat part A with the car slowing down(c) describe what happens to you as the car slowsdown(d) suppose now that the bench is not slippery. as the carslows down, you stay on the bench and dont slide off. what force isresponsible for you deceleration?

Answer 1

A)

The forces acting on you are:

• The gravitational pull of the Earth (an others Celestial objects)

• The Normal Force that balance the gravitational pull and points upward.

That is. There is not need for any other force, cause the car its going at constant speed, so the acceleration its zero, as the net force its mass multiplied by acceleration, the net force is zero.

B)

The forces acting on you are:

• The gravitational pull of the Earth (an others Celestial objects)

• The Normal Force that balance the gravitational pull and points upward.

That is. Again. The car its slowing down. But, it cant apply a force in you against the direction of movement to slow you down.

C)

As you can't be slowed down, you will go forward at the same speed you had when the car went steady, and will crash against whatever its in front of you.

D)

The friction force, will pull you against the direction of movement, and slow you down will the car slows down.