Force Diagrams

Question 1

Forces are vectors.

Answer 1

Forces are vectors.

Question 2

If a car is driving at a constant speed is the weight force bigger, smaller or the same size as the support force?

Answer 2

They’re the same size, otherwise, the car would be floating or sinking.

Question 3

If a car is driving at a constant speed is there a net force in the horizontal direction? Why or why not?

Answer 3

There can’t be a net force in the horizontal direction, otherwise, the car wouldn’t be travelling at a constant speed.

Question 4

If a boat is speeding up is the weight force bigger than, smaller than, or the same size as the buoyancy force?

Answer 4

The weight force is still the same size as the buoyancy force, otherwise it would sink in the water or float into the air.

Question 5

If a boat is speeding up is there a net force in the horizontal direction? Why or why not?

Answer 5

There has to be a net force to the right so that the boat speeds up.

Question 6

If a boat is speeding up explain how the relative sizes of each force create this acceleration.

Answer 6

For the boat to speed up, it must have a net force in the direction it is moving. If we assume
the boat is moving to the right, then it must have a net force to the right. This means that the thrust is bigger than the drag, which creates the net force.