Newtons Laws

Question 1

Weight (Fg)

Answer 1

The gravitational force the Earth exerts on any object on or near its surface


Question 2

Normal force (FN)

Answer 2

The perpendicular force exerted by a surface on an object in contact with it

Question 3

Frictional force due to a surface (Ff)

Answer 3

The force that opposes the motion of an object and acts parallel to the surface with which the object is in contact


Question 4

Newton’s First Law of Motion

Answer 4

An object continues in a state of rest or uniform (moving with constant) velocity unless acted upon by a net or resultant force


Question 5

Newton’s Second Law of Motion

Answer 5

When a net force, Fnet, is applied to an object of mass, m, it accelerates in the direction of the net force. The acceleration, a, is directly proportional to the net force and inversely proportional to the mass


Question 6

Newton’s Third Law of Motion

Answer 6

When object A exerts a force on object B, object B simultaneously exerts an oppositely directed force of equal magnitude on object A


Question 7

Newton’s Law of Universal Gravitation

Answer 7

Every particle with mass in the universe attracts every other particle with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centres


Question 8

Gravitational field

Answer 8

The force acting per unit mass

Question 9

Tension in a string/cable

Answer 9

The tension in a string/cable is the same throughout the entire string/cable.