Science

Question 1

What’s the formula for pressure?

Answer 1

P = f / a

f = force a=unit area

Question 2

What is the unit for pressure?

Answer 2

Pascals

Question 3

What is the formula for a right triangle?

Answer 3

AB / 2

A = height b= base

Question 4

What are light sources referred to as?

Answer 4

They are reffered to as luminous.

Question 5

What are the three ways light can affect objects?

Answer 5

It can be transmitted, reflected or absorbed.

Question 6

What happens when an object absorbs light?

Answer 6

It is converted into thermal energy and heats the object up.

Question 7

Does light need a medium?

Answer 7

No

Question 8

What happens to light that is far away?

Answer 8

It spreads out and thus gets dimmer.

Question 9

What is the initial ray of light called in a reflection?

Answer 9

Incident ray

Question 10

What is another name for a flat mirror

Answer 10

A plane mirror

Question 11

What are the two types of images?

Answer 11

Virtual and real

Question 12

What is a real image?

Answer 12

Its an image you don’t need to look through anything to see.

Question 13

What is the law of reflection?

Answer 13

It states that angle of incidence = angle of reflection

Question 14

What is a laterally inverted image?

Answer 14

Its an image that is flipped to be opposite of the object.

Question 15

What is refraction?

Answer 15

It is the bending of light

Question 16

How do you calculate angle of refraction?

Answer 16

Same as reflection but on the other side of the material.

Question 17

Do refracted objects appear higher or lower than they are?

Answer 17

Higher

Question 18

What does the speed in different materials depend on?

Answer 18

It depends on the density of the material.

Question 19

How do you calculate the refractive index?

Answer 19

Speed of light in a vacuum / speed of light in the medium

Question 20

How many times does light refract in an object?

Answer 20

2 times

Question 21

What are the colours of the white light spectrum?

Answer 21

Red, orange, yellow, green, blue, indigo and violet

Question 22

What is the process of splitting white light into a spectrum called?

Answer 22

Dispersion

Question 23

Why can you only see a rainbow when the sun is behind you?

Answer 23

Light reflects backwards off of raindrops so can only be seen behind.

Question 24

How can you recombine the light spectrum?

Answer 24

By using another prism upside down.

Question 25

What are the three primary colours?

Answer 25

Red, green and blue

Question 26

How do televison coloured screens work?

Answer 26

They work by emitting primary colours and placing a filter over them.

Question 27

What happens to the image formed on the retina?

Answer 27

It is upside down

Question 28

Why would an object look red?

Answer 28

It's because the object absorbed all other forms of light except red which it reflects.

Question 29

Is light a wave or a particle?

Answer 29

Wave-particle

Question 30

What transfers signals from your eye to your brain?

Answer 30

The optic nerve

Question 31

Where is the retina?

Answer 31

At the back of the eye

Question 32

What is the muscle that controls the size of the pupil called?

Answer 32

The iris

Question 33

What is the hole light goes in called?

Answer 33

The pupil

Question 34

What is the transparent outer layer of the eye called?

Answer 34

The cornea

Question 35

What part of the eye focuses light on the retina? | besides the cornea

Answer 35

The lens

Question 36

What is the critical angle in refraction?

Answer 36

It's the angle where refracted light is at 90 degrees to the normal

Question 37

What is internal reflection?

Answer 37

It's when the refracted angle exceeds the critical angle

Question 38

What is the name of the effect which allows raindrops to cause a rainbow?

Answer 38

Dispersion

Question 39

What is a regular reflection?

Answer 39

It's when light reflects off of a smooth surface.

Question 40

Does a blue filter absorb or let blue pass through?

Answer 40

It lets blue pass through and absorbs everything else.

Question 41

What happens if you remove a magnet from steel after putting it near one?

Answer 41

The steel remains magnetized.

Question 42

How can you demagnetize an object?

Answer 42

By heating it up or hitting it with a hammer

Question 43

How could you see a magnet?

Answer 43

By using a plotting compass or iron filings

Question 44

What is an electromagnet?

Answer 44

It's a magnet that is powered by electricity.

Question 45

What can make an electromagnet stronger?

Answer 45

Coils

Question 46

What influences the strength of an electromagnet?

Answer 46

* The number of turns of the coil * The voltage * The type of core (magnetic materials are better)

Question 47

What is the advantage of an electromagnet over regular magnets?

Answer 47

You can turn it on and off

Question 48

What are relays?

Answer 48

They're a device to use current in one circuit to power another circuit. | usually when it's too dangerous to handle normally

Question 49

What are some uses of electromagnets?

Answer 49

Relays, fire doors, electric bells and MRI machines

Question 50

What is the difference between primary and secondary energy sources?

Answer 50

Primary comes from nature while secondary comes from refined primaries.

Question 51

What will happen if you move a magnet towards a voltmeter?

Answer 51

It will induce a voltage.

Question 52

What will happen if you move a South magnet towards a voltmeter instead of North?

Answer 52

The direction of movement for the coil will be reversed.