Newtons Laws

Question 1

Define Force

Answer 1

The vector sum of all the forces on an object gives a net or resultant force.

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Question 2

Describe the outcome of a situation where an object has forces of equal magnitude in perfeclty opposing directions acting on it at the same time

Answer 2

There is no ‘net’ or resultant force on the mass: the forces are balanced.

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Question 3

State Newton’s First Law (the law of inertia)

Answer 3

Objects moving in free space with no forces acting on them will continue to move in a straight line at a constant velocity until a force causes them to change speed or direction.

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Question 4

State Newton’s Second Law

Answer 4

If there is a resultant force on an object, it accelerates in the direction of that force. Its acceleration is directly proportional to the force, and inversely proportional to the object’s mass.
Meaning:
F = ma
F in N
m in kg
a in ms^-2

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Question 5

State Newton’s Third Law

Answer 5

For every action there is an equal and opposite reaction. Forces always come in pairs.
Newton’s third law applies only to forces between objects. Pairs of action and reaction forces are of the same kind.

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