P5.2 Contact and non-contact forces

According to Newton's Third Law, what happens when two objects interact?

• Only one object experiences a force.

• They exert equal and opposite forces on each other.

• The larger object exerts a greater force.

What is a "contact force"?

• A force that acts over a distance.

• A force that requires objects to be in physical contact to interact.

• A force caused by gravity.

Which of the following is an example of a non-contact force?

• Friction.

• Air resistance.

• Gravity.

What does the weight of an object represent?

• Its mass.

• The force of gravity acting on it.

• Its density.

When a car moves forward, what is the direction of the friction on the tyres by the road?

• In the backward direction.

• In the forward direction.

• Perpendicular to the direction of motion.

If you push on a door, what force does the door exert back on you?

• A smaller force in the same direction.

• An equal and opposite force.

• No force, as you are the one applying the force.

What kind of forces are applied when a person applies toothpaste from a tube?

• Non-contact forces.

• Only pushing forces.

• Pushing, pulling, squeezing, twisting, or shaping forces.

What is the relationship between the resultant force on an object and its acceleration?

• Acceleration is always in the opposite direction of the force.

• The resultant force causes the object to accelerate.

• Acceleration only occurs if there are no forces acting.

When you walk, what type of force allows you to move forward?

• Magnetic force.

• Normal contact force from the ground.

• Gravitational force.

What factors influence how much a car can accelerate or decelerate?

• Only the engine power.

• The friction between the tyres and the road.

• The colour of the car.