Forces

Question 1

What is a force?

Answer 1

A force is a push or a pull exerted on an object.

Forces can vary in size and direction.

Question 2

What units are used to measure force?

Answer 2

Newton (N)

The unit is named after Sir Isaac Newton, who formulated the laws of motion.

Question 3

What happens when you gently push your hands against a partner’s hands?

Answer 3

You observe an exertion of force in both directions.

This demonstrates the concept of action and reaction forces.

Question 4

Fill in the blank: A force can be described as a _______ or a pull.

Answer 4

push

Forces can act on objects in various ways.

Question 5

What forces act on you even when standing still?

Answer 5

1. Gravity
2. Air particles hitting your body
3. Normal force from the ground

These forces are constantly at work.

Question 6

True or False: Forces usually act alone.

Answer 6

False

Forces often act in pairs, demonstrating action and reaction.

Question 7

What can forces change in an object?

Answer 7

Forces can change the shape of an object, cause it to move, cause a moving object to stop or change its direction.

Examples include flattening putty, moving a cart, and hitting a ball.

Question 8

True or False: Forces can be seen directly.

Answer 8

False

Forces themselves cannot be seen, but their effects on objects can be observed.

Question 9

What are the two broad categories of forces?

Answer 9

Contact forces and non-contact forces

Question 10

Define tensile force.

Answer 10

Something being stretched

Question 11

What are contact forces?

Answer 11

Forces that result when two objects are touching each other

Question 12

Provide examples of contact forces.

Answer 12

• Tensile force
• Compression force
• Friction force

Question 13

What is a compression force?

Answer 13

When something is squashed

Question 14

What is friction force?

Answer 14

A force that resists motion and causes a heating effect

Question 15

What are non-contact forces also known as?

Answer 15

Field forces

Question 16

What are examples of non-contact forces?

Answer 16

• Gravitational forces
• Electrostatic forces
• Magnetic forces

Question 17

Define gravitational forces.

Answer 17

The forces that objects have on each other due to their masses

Question 18

What is the direction of the gravitational force that Earth exerts on objects?

Answer 18

Always downwards

Question 19

What is the relationship between weight and mass?

Answer 19

Weight is determined by gravitational force; mass is the amount of matter in an object

Question 20

How is weight measured?

Answer 20

In Newtons (N)

Question 21

How is mass measured?

Answer 21

In kilograms (kg)

Question 22

Does an object’s mass change regardless of its location?

Answer 22

No, an object’s mass does not change

Question 23

What is the weight of a person on the moon compared to Earth?

Answer 23

1/6th of that on Earth

Question 24

If an object has a weight of 600 N on Earth, what would its weight be on the moon?

Answer 24

100 N

Question 25

What is a magnetic force?

Answer 25

Magnets exert a non-contact force on other magnetic materials.

Question 26

Which metals are magnetic?

Answer 26

Iron, cobalt, and nickel are the only three magnetic metals.

Question 27

What are the two ends of a magnet called?

Answer 27

The two ends of a magnet are known as the north pole and south pole.

Question 28

What is the magnetic field?

Answer 28

The area around the magnet in which another object experiences a force is known as the magnetic field.

Question 29

What happens when opposite poles of magnets interact?

Answer 29

Opposite poles will attract each other.

Question 30

What happens when like poles of magnets interact?

Answer 30

Like poles will repel each other.

Question 31

What is the effect of north poles on south poles?

Answer 31

North poles are attracted to south poles.

Question 32

What is the effect of north poles on other north poles?

Answer 32

North poles will be repelled by another north pole.

Question 33

How can you observe magnetic effects?

Answer 33

Use a bar magnet to see which objects are affected by the magnet.

Question 34

What is the Earth's magnetic field used for?

Answer 34

Direction and protection from Solar winds ## Footnote The Earth's magnetic field functions similarly to a bar magnet.

Question 35

What are the two types of electric charges?

Answer 35

Positive charges and Negative charges ## Footnote These charges interact with each other through electrostatic forces.

Question 36

What is static electricity?

Answer 36

Charges that stay where you put them ## Footnote Static electricity occurs when charges are placed on insulators like glass, plastic, rubber, and wood.

Question 37

What materials are classified as insulators?

Answer 37

Glass, plastic, rubber, and wood ## Footnote Insulators do not allow charges to move freely through them.

Question 38

What occurs when two objects with like charges are near each other?

Answer 38

They will repel or push each other ## Footnote This is an example of repulsive electrostatic forces.

Question 39

What happens when two objects with unlike charges are near each other?

Answer 39

They will attract or pull each other ## Footnote This is an example of attractive electrostatic forces.

Question 40

Fill in the blank: Materials like glass and plastic are called _______.

Answer 40

insulators