3.1 Dynamics

Question 1

3.1.1 Mass is the property of an object that

Answer 1

Is the property of an object that resists change in motion.

Question 2

3.1.2 a) What is the relationship between Force, Mass, and acceleration and what units are used?
b) and what two properties are in the same direction?

Answer 2

a) F = ma
Force in Newtons (N)
Mass in (kg)
Acceleration in (ms^-2)

b) Acceleration and resultant force always act in the same direction.

Question 3

3.1.3 Define linear momentum

Answer 3

Linear momentum is the product of mass and velocity.

Question 4

3.1.4 Define force:

Answer 4

Force is the rate of change of momentum. Force = Momentum/time

Question 5

3.1.5 State Newton’s first law:

Answer 5

Objects either stay at rest or remain in uniform motion unless acted on by an external resultant force.

Question 6

3.1.5 State Newton’s second law:

Answer 6

The rate of change of momentum of an object is directly proportional to the resultant force applied and is in the direction of the resultant force.

Question 7

3.1.5 State Newton’s third law:

Answer 7

When two objects interact they exert equal and opposite forces on each other.

Question 8

3.1.5 What are the conditions of Newton’s third law pairs?

Answer 8

They must be the same type of force.
They must act on the same pair of objects.
Must have the same line of action, and magnitude but in an opposite direction.
Must act on a different object within the pair.

Question 9

3.1.6 What is the effect of a gravitational field on a mass?

Answer 9

The concept of weight.

Question 10

3.1.6 What is the weight of an object equal to?

Answer 10

It is equal to the product of its mass and the acceleration of free fall.