Forces

Question 1

A force can be ….

Answer 1

Push and pull

Question 2

A force can be measured by a newton meter

Question 3

What is a force?

Answer 3

A force can be a push or a pull.

Question 4

How can forces be measured?

Answer 4

Forces can be measured using a newtonmeter.

Question 5

What unit is used to measure forces?

Answer 5

Forces are measured in newtons (N).

Question 6

What are contact forces?

Answer 6

Contact forces occur when objects are touching, for example:
* friction
* drag forces (air resistance and water resistance)
* support forces (e.g., reaction forces)

Question 7

What are non-contact forces?

Answer 7

Non-contact forces work at a distance, for example:
* gravity
* magnetic force
* electrostatic force

Question 8

What are interaction pairs?

Answer 8

Forces always occur in pairs called interaction pairs.

Question 9

What happens when forces are balanced?

Answer 9

When forces are balanced, they are the same size and act in opposite directions, cancelling each other out.

Question 10

What is equilibrium in terms of forces?

Answer 10

An object is in equilibrium when balanced forces cancel out.

Question 11

What are unbalanced forces?

Answer 11

Unbalanced forces are when the forces are not the same size and do not cancel each other out.

Question 12

What effect do unbalanced forces have on an object?

Answer 12

The larger the difference between unbalanced forces, the quicker the object will change speed.

Question 13

Define gravity.

Answer 13

Gravity is a non-contact force that attracts objects towards each other.

Question 14

What is Hooke’s Law?

Answer 14

Hooke’s Law states that the force exerted by a spring is proportional to its extension.

Question 15

What is a reaction force?

Answer 15

A reaction force is a support force that counteracts the weight of an object.

Question 16

What is friction?

Answer 16

Friction is a force that opposes the motion of objects sliding against each other.

Question 17

What is air resistance?

Answer 17

Air resistance is a type of drag force that opposes the motion of an object through air.

Question 18

What is water resistance?

Answer 18

Water resistance is a drag force that opposes the motion of an object through water.

Question 19

What is upthrust?

Answer 19

Upthrust is the upward force exerted by a fluid on an object submerged in it.

Question 20

Fill in the blank: A solid moving through a gas has to push _______ out of the way.

Answer 20

particles

Question 21

What is the effect of drag forces?

Answer 21

Drag forces can slow down the motion of objects.

Question 22

What is the significance of weight in making an object sink or float?

Answer 22

Your weight compared to the upthrust determines if an object sinks or floats.

Question 23

What is the role of a support force?

Answer 23

A support force counteracts the weight of an object.

Question 24

True or False: All forces can be classified as either contact or non-contact.

Answer 24

True

Question 27

What is friction?

Answer 27

A contact force that occurs when two objects move against each other.

Question 28

How can friction be reduced?

Answer 28

By adding lubrication (e.g., oil or grease).

Question 29

Why is friction useful?

Answer 29

* Needed to walk across surfaces * Required for bike brakes to work.

Question 30

What is a drag force?

Answer 30

A force that occurs when a solid moves through a liquid or gas, pushing particles out of the way.

Question 31

What are examples of drag forces?

Answer 31

* Water resistance * Air resistance.

Question 32

How can drag forces be useful?

Answer 32

They can help slow something down, such as using parachutes.

Question 33

What happens when you stand on the floor?

Answer 33

Your weight pushes the particles in the floor together.

Question 34

What is a reaction force?

Answer 34

A support force that balances the weight of an object.

Question 35

What is another example of a support force?

Answer 35

Upthrust.

Question 36

What happens to particles when weight is applied?

Answer 36

The bonds between the particles are compressed.

Question 37

What does making an object more streamlined do?

Answer 37

Reduces the drag forces on it.

Question 38

Define 'interaction pair'.

Answer 38

A pair of forces that are equal in size and opposite in direction.

Question 39

What is the elastic limit?

Answer 39

The maximum extent to which a solid can be stretched without permanent deformation.

Question 40

What is tension?

Answer 40

The force transmitted through a string, rope, or wire when it is pulled tight.

Question 41

What is the definition of mass?

Answer 41

The amount of matter in an object, measured in kilograms.

Question 42

What is weight?

Answer 42

The force exerted on an object due to gravity.

Question 43

What is the relationship between weight and mass?

Answer 43

Weight is proportional to mass and gravity.

Question 44

What is Hooke's law?

Answer 44

The principle that the force needed to extend or compress a spring is proportional to the distance it is stretched or compressed.

Question 45

Fill in the blank: A solid moving through a liquid experiences ______.

Answer 45

drag force.

Question 46

True or False: Friction can sometimes be detrimental.

Answer 46

True.

Question 47

What is lubrication?

Answer 47

A substance used to reduce friction between surfaces in mutual contact.

Question 48

What is a non-contact force?

Answer 48

A force that does not require direct contact between objects. ## Footnote Examples include electrostatic force, magnetic force, and gravitational force.

Question 49

What is a field in physics?

Answer 49

A special region where certain objects experience a force. ## Footnote Examples include gravitational fields and magnetic fields.

Question 50

What does a mass experience in a gravitational field?

Answer 50

A force due to gravity. ## Footnote The gravitational field strength on Earth is about 10 N/kg.

Question 51

What force does a charged object experience in an electrostatic field?

Answer 51

A force due to electrostatic interactions.

Question 52

What is weight and how is it measured?

Answer 52

Weight is a force measured in newtons (N). ## Footnote Weight is calculated as weight (N) = mass (kg) x gravitational field strength (N/kg).

Question 53

What is the difference between mass and weight?

Answer 53

Mass is the amount of 'stuff' something is made of and is measured in kilograms (kg). Weight is the force due to gravity acting on that mass.

Question 54

How does gravitational field strength affect weight?

Answer 54

Your weight depends on the gravitational field strength, but your mass remains constant everywhere.

Question 55

What does Hooke's law state?

Answer 55

The extension of a spring doubles when you double the force applied to it. ## Footnote This indicates a linear relationship between force and extension.

Question 56

What is extension in the context of springs?

Answer 56

The amount a spring stretches when a force is applied.

Question 57

What force causes a spring to return to its original length?

Answer 57

Tension, unless the spring has exceeded its elastic limit.

Question 58

What is water resistance?

Answer 58

A type of frictional force that opposes the motion of a solid moving through a liquid.

Question 59

What is the formula to calculate weight?

Answer 59

Weight (N) = mass (kg) x gravitational field strength (N/kg).

Question 60

True or False: The field strength gets weaker as you move away from a mass, magnet, or charged object.

Answer 60

True.

Question 61

What is the unit of measurement for gravitational field strength?

Answer 61

N/kg.

Question 62

Fill in the blank: The amount a spring stretches is called _______.

Answer 62

extension.

Question 63

What are the types of forces mentioned?

Answer 63

* Electrostatic force * Magnetic force * Upthrust * Friction * Tension * Water resistance