Science ~ Forces

Question 1

What is a force?

Answer 1

A push or pull on an object

Question 2

What are forces measured in?

Answer 2

Newtons, N

Question 3

What are contact forces? Give examples

Answer 3

The objects are touching for the force to act

Examples:
friction, air resistance, tension, and normal contact force

Question 4

What are non-contact forces? Give examples

Answer 4

The objects do not need to touch for the force to act

Examples:
magnetic force, gravitational force, electrostatic force

Question 5

How are forces represented on a diagram?

Answer 5

• By an arrow

Question 6

What is meant by the term resultant force?

Answer 6

Overall force acting on an object

Question 7

How can you calculate resultant force from a diagram?

Answer 7

• If the forces are in the same direction add them
• If the forces are in opposite directions subtract them

Question 8

What will happen to an objects motion if the resultant force is 0?

Answer 8

The object will remain stationary or at a constant speed.

Question 9

What will happen to an objects motion if the resultant force is above 0?

Answer 9

The objects motion will change.

Question 10

What is weight?

Answer 10

The force acting on an object due to gravity

Question 11

What is the equation for weight?

Answer 11

• Weight (N) = mass (kg) x gravitational field strength (N/kg)
• W = mg

Question 12

What is mass?

Answer 12

The amount of matter an object is made up of

Question 13

What is the gravitational field strength on Earth?

Answer 13

9.8 N/kg

Question 14

How does location affect gravitational field strength?

Answer 14

Closer objects, the stronger gravitational field strength

Question 15

What is the relationship between mass and weight?

Answer 15

Weight and mass are directly proportional.

Question 16

What does directly proportional mean?

Answer 16

• As one value increases the other increases by the same percentage
• Straight line of best fit through the origin

Question 17

What is a permanent magnet?

Answer 17

Permanent magnet is an object that is magnetic all the time

Question 18

What is an induced magnet?

Answer 18

Object that becomes a magnet when placed in a magnetic field

Question 19

What is a magnetic field?

Answer 19

Magnetic field is the region where the force of magnetism acts

Question 20

What happens when two like poles of a magnet come together?

Answer 20

Two like poles will repel

Question 21

What happens when two opposite poles of a magnet come together?

Answer 21

Opposite poles will attract

Question 22

What is the direction of a magnetic field line?

Answer 22

From the north (seeking) pole of a magnet to the south (seeking) pole of the magnet

Question 23

Draw the magnetic field lines on this bar magnet.

Answer 23

See image here:
https://tinyurl.com/yrycl3m5

Question 24

Name 4 magnetic materials:

Answer 24

Iron, Nickel, Steel, Cobalt

Question 25

What is the source of the Earth’s magnetic field?

Answer 25

Earths’ core is made of iron and the source of the magnetic field

Question 26

Draw the magnetic field lines on the Earth.

Answer 26

See image here: https://tinyurl.com/yvweqfzj

Question 27

What is the relationship between extension and force applied?

Answer 27

Extension is directly proportional to the force applied unless it has exceeded its limit of proportionality

Question 28

What happens, in terms of energy, when you stretch or compress an object?

Answer 28

* Energy is transferred to elastic potential energy store of the object * Work is done

Question 29

What is a linear relationship?

Answer 29

- Increase one variable and the other variable increases by the same percentage - Straight line of best fit