physics

Question 1

What is a force?

Answer 1

A push or a pull

Question 2

What units are used to measure force?

Answer 2

Newtons (N)

Question 3

What is force measured by?

Answer 3

Newton Balance

Question 4

What direction will an object move when a force is unbalanced?

Answer 4

It will move in the direction of the larger force

Question 5

The larger the unbalanced force…

Answer 5

the greater the acceleration

Question 6

To find total force acting on an object

Answer 6

forces acting in the same direction can be added together and forces acting in opposite directions can be subtracted

Question 7

what is friction?

Answer 7

friction is when two surfaces rub together

Question 8

What does friction always do?

Answer 8

opposes motion and slows things down

Question 9

What increases friction?

Answer 9

rough surfaces or surfaces with large surface area

Question 10

What increases grip?

Answer 10

Increasing friction

Question 11

What is water resistance?

Answer 11

When water rubs on a body

Question 12

What is streamlining?

Answer 12

Streamlining is when we change the shape of an object to decrease air or water resistance.

Question 13

What is air resistance?

Answer 13

When air rubs on a body

Question 14

What also reduces friction?

Answer 14

lubrication

Question 15

What are streamlined objects usually like?

Answer 15

Streamlined objects are smooth and curved are smooth and curved and usually close to the ground.

Question 16

What do cyclists do to reduce friction?

Answer 16

They wear skin tight clothing, wear streamlined helmets and bend over their handlebars to reduce friction

Question 17

What do swimmers do to reduce friction?

Answer 17

They wear skin tight clothing, shave hair from their arms and legs and wear swimming caps

Question 18

What do FINA state that swimmers must do when swimming?

Answer 18

They state that swimmers must break the surface before 15m, because swimming underwater is easier and faster, using less energy

Question 19

What is newton’s third law of motion?

Answer 19

Newton’s third law of motion states that for every acting force, there is an equal and opposite reaction force.

Question 20

Give an example of Newton’s third law

Answer 20

In swimming, we push water backwards, and the water pushes us forward.

Question 21

What are the four main types/strokes of swimming?

Answer 21

Freestyle, breaststroke, backstroke and butterfly

Question 22

how do parachutes work?

Answer 22

Parachutes have a large surface area, they increase air resistance and slow things down.

Question 23

What is an object called when it is kicked or thrown?

Answer 23

a projectile.

Question 24

What is the name of the curved path a projectile follows?

Answer 24

a trajectory.

Question 25

Do all objects fall to earth at the same rate?

Answer 25

yes, regardless of their mass due to the pull of gravity.

Question 26

What is vertical motion caused by?

Answer 26

It is caused by gravity.

Question 27

When does vertical motion increase?

Answer 27

When gravity is present.

Question 28

When does horizontal motion decrease?

Answer 28

When air resistance is present.

Question 29

What is the range of a projectile?

Answer 29

It is the horizontal distance.

Question 30

What is horizontal distance affected by?

Answer 30

the force of the kick and the angle.

Question 31

How do you measure speed in m/s?

Answer 31

measure the distance travelled in one second.

Question 32

How to you calculate the speed in m/s

Answer 32

Calculate distance divided by time.

Question 33

What units are used in a distance/time calculation?

Answer 33

meters/second (m/s)

Question 34

What is reaction time?

Answer 34

Reaction time is the time between a stimulus (something happening) and a muscular response (the body doing something).

Question 35

When we see a stimulus, how does this lead to our muscles moving?

Answer 35

We see the stimulus with our eyes. The eyes send a message to the visual cortex in the brain. The brain then sends a message to our motor cortex. The motor cortex sends a message to the spinal cord, which sends a message to make the muscles move.

Question 36

Give an example of when reaction time is important.

Answer 36

in sports (like racing) reaction time is important because of the small margins between winning and losing.