03 Dynamics

Question 1

What are the 4 forces in nature?

Answer 1

-strong nuclear force
-electromagnetic force
-weak nuclear force
‐gravitational force

Question 2

Put the 4 forces in nature in order from strongest to weakest?

Answer 2

strongest
Strong nuclear force
Electromagnetic force
Weak nuclear force
Gravitational force
Weakest

Question 3

What does strong nuclear force (SNF) do?

Answer 3

Binds the nucleus

Question 4

What does Weak nuclear force do?

Answer 4

Changes quark flavour

Question 5

What does Electromagnetic force do?

Answer 5

Force binds atoms

Question 6

What does gravitational force do?

Answer 6

Binds the solar system

Question 7

Which of the forces in nature prevents the nuclei from collapsing?

Answer 7

Strong nuclear force

Question 8

Which of the forces in nature binds neutrons together in the nucleus?

Answer 8

Strong nuclear force

Question 9

Which of the forces in nature binds protons together in the nucleus?

Answer 9

Strong nuclear force

Question 10

Which of the forces in nature keeps electrons orbiting the nucleus?

Answer 10

Electromagnetic force

Question 11

Which of the forces in nature causes the normal contact force?

Answer 11

Electromagnetic force

Question 12

Which of the forces in nature causes drag?

Answer 12

Electromagnetic force

Question 13

Which of the forces in nature causes air resistance?

Answer 13

Electromagnetic force

Question 14

Which of the forces in nature causes beta radiation?

Answer 14

Weak nuclear force

Question 15

Which of the forces in nature red-giant stars to collapse?

Answer 15

Gravitational force

Question 16

Which of the forces in nature changes quark flavour?

Answer 16

Weak nuclear force

Question 17

Which of the forces of nature keeps the earth orbiting the sun?

Answer 17

Gravitational force

Question 18

What is force measured in?

Answer 18

Newton’s (N)

Question 19

What is the definition of a Newton?

Answer 19

A force of one Newton gives a mass of 1 kg and an acceleration of 1 m s‐²

Question 20

What is weight equal to?

Answer 20

Weight=force of gravity=mg

Question 21

What is the definition of gravitational field strength?

Answer 21

The force due to gravity on a mass of 1 kilogram.

Question 22

What are the units for gravitational field strength?

Answer 22

m s‐²
N kg‐¹

Question 23

What is mg?

Answer 23

Force of gravity

Question 24

How do you lable an objects weight on a diagram?

Answer 24

With a downward arrow from the centre of mass labelled ‘mg’.

Question 25

In which direction does friction happen?

Answer 25

In the opposite direction to the motion of the object.

Question 26

When does friction decrease?

Answer 26

When the 2 surfaces are made smoother and the weight of the object decreases.

Question 27

When does friction increase?

Answer 27

When the 2 surfaces are made rougher and the weight of the object increases.

Question 28

What are frictional forces acting on an object moving through a gas or liquid also known as?

Answer 28

Fluid friction, drag and air resistance.

Question 29

What does normal mean?

Answer 29

Perpendicular

Question 30

At what angle does the normal contact force act?

Answer 30

At 90° (perpendicular) to the surfaces in contact.

Question 31

What is normal contact force?

Answer 31

A force acting perpendicular to a surface.

Question 32

What type of diagram shows the forces acting on a car?

Answer 32

A free body diagram

Question 33

What is the resultant force?

Answer 33

The overall or net effect of all the forces of an object.

Question 34

What does newton's 1st law of motion state?

Answer 34

An object remains at rest or continues with constant velocity unless acted upon by a resultant force.

Question 35

If opposite arrows on a free body diagram are the same length how do you describe them?

Answer 35

Equal and opposite.

Question 36

In a free body diagram if the arrows are equal and opposite, what is the resultant force?

Answer 36

0N

Question 37

If the resultant force is 0N what is concluded about the speed?

Answer 37

It is constant / no acceleration

Question 38

What does newton's 2nd law of motion state?

Answer 38

An objects acceleration is directly proportional to the resultant force acting on the object and inversely proportional to its mass (f = ma)

Question 39

What does newton's 3rd law state?

Answer 39

If body A exerts a force on a body B then body B exerts and equal but opposite force on body A.

Question 40

What is the criteria for Newtons 3rd law forces?

Answer 40

1. Be equal in magnitude 2. Act along the same line of action 3. Be forces of the same kind 4. Act in opposite directions.

Question 41

What is terminal velocity?

Answer 41

The maximum velocity achieved when there is no resultant force acting on a falling body