Motions 2

Question 1

What is friction?

Answer 1

The force that acts when one surface moves over another.
It always opposes the motion (this means that if an object is trying to slide to the left, friction will act to the right)
Friction converts kinetic energy into heat.

Question 2

What are the two types of friction?

Answer 2

-Static friction
Occurs when the two surfaces are trying to slide over each other.
-dynamic friction
Occurs when one of the surfaces is actually moving.
Static friction is greater than dynamic friction

Question 3

What is Newton’s 1st law?

Answer 3

In the absence of a resultant force an object will remain at rest or continue to move at a constant velocity.
ie. balanced forces do not produce acceleration.

Question 4

What is Newton’s 2nd law?

Answer 4

The acceleration of an object is directly proportional to the resultant force acting on it and inversely proportional to the mass f the object.

Question 5

What is Newton’s 3rd law?

Answer 5

If body A exerts a force on body ab, there is an equal and opposite force exerted on A by B.
(Sometimes called the reaction force.

Question 6

What is a Newton?

Answer 6

A force equal to 1N will accelerate 1kg at 1m/s

Question 7

Equation for force?

Answer 7

Force = mass x acceleration

Question 8

How do you work out the average velocity?

Answer 8

Av. Velocity = Displacement/time