1.3 Dynamics

Newtons 3rd Law

• If body A exerts

• that is equal in magnitude

• then body B exerts a force

• and opposite in direction on body A.

• a force on body B

What is the definition of Newtons 2nd Law?

F=?

What is the definition of momentum?

Momentum, p, is an objects ​ (a)   multiplied by its ​ (b)   .

• mass
• velocity
• speed
• bananas
• distance
• force
• time

What is an alternative definition of Newton's 2nd Law?

The Principle of the Conservation of Momentum

The total ​ (a)   of a system ​ (b)   a collision is ​ (c)   to the total momentum ​ (d)   a collision as long as there is no external ​​ (e)   force.

• momentum
• before
• equal
• after
• resultant
• greater than
• less than
• bananas
• energy
• explosion

True or False? An elastic collision is one in which the kinetic energy before and after a collision is the same.

• True

• False

Select all the options that apply.

In an inelastic collision....

• energy may be dissipated into raising the internal energy of the surroundings (heat)

• some kinetic energy is transferred to other types of energy

• the kinetic energy before the collision/explosion is different to the kinetic energy afterwards.

• energy may be lost as work done against friction

Which of the following must be true if an object is accelerating?

• It is going really fast.

• It is moving away from the frame of reference point.

• Balanced forces are acting upon it.

• Unbalanced forces are acting upon it.

A body at rest remains at rest, or, if in motion, remains in motion at a constant velocity unless acted on by a net external force. This statement is known as

• Law of Inertia

• Law of Acceleration

• Law of Interaction

• Law of Gravitation

• Conservation of Energy

1 Newton of force is equal to

• 1 kg m/s

• 1 kg m/s²

• 1 kg /ms²

• 1 m/ kg s²

• 1 s/ kg m