1 - M&F - Newtons Laws

Question 1

What is Newton’a First Law?

Answer 1

• If the resultant force on a body is zero, the body is moving at a constant velocity or is at rest
• If the resultant force is not zero, the speed and/or direction of the body changes

Question 2

What is Newton’s Second Law?

Answer 2

force = mass x acceleration

Question 3

What happens to an object moving in a Circular Orbit at constant speed?

Answer 3

• It is constantly changing direction, so constantly changing velocity
• This means it’s accelerating

Question 4

What is the result of an object in Circular Motion?

Answer 4

There must be a resultant force on it, known as centripetal force acting towards the centre of the circle

Question 5

What is Inertial Mass?

Answer 5

• A measure of how difficult it is to change the velocity of an object
• The ratio of force/acceleration

Question 6

What is Newton’s Third Law?

Answer 6

When two forces interact, the forces they exert on each other are equal and opposite

Question 7

How does Newton’s Third Law describe equilibrium situations?

Answer 7

When something pushes against something, an equal force (normal contact) pushes back. The forces are the same size
eg. a book resting on a table is equilibrium, weight of book pulls it down and the ncf from the table pushes it up