Forces

Question 1

What are contact forces? Give examples.

Answer 1

Forces that require physical contact, like friction and push/pull forces.

Question 2

What are non-contact forces? Give examples.

Answer 2

Forces that act at a distance, like gravity and magnetic force.

Question 3

Define gravity.

Answer 3

A force that pulls objects toward each other, such as towards the Earth.

Question 4

Define Friction Force.

Answer 4

Force that opposes motion. One surface moves against another (kinetic energy -> heat energy). If friction and thrust force are equal and opposite the forces are balanced. This is a contact force.

Question 5

Define Thrust Force.

Answer 5

Force that pushes something forward usually through reaction of accelerating mass of gas. Opposite of friction force and a contact force.

Question 6

Define Support Force.

Answer 6

Opposite to gravity force. If in air - lift (upwards force by air). If in water -> buoyancy (upwards force by water. This is a contact force.

Question 7

Explain what is meant when forces are balance and unbalanced.

Answer 7

Equal Forces: Acting in opposite directions, causing no change in motion.

Unbalanced Forces: Causing a change in ab objects motion.