Physics (P6)

Question 1

What are ultrasound waves?

Answer 1

Waves above the frequency of what humans can hear

Question 2

What is the range of human hearing?

Answer 2

20 to 20,000 Hz

Question 3

Name 3 uses of ultrasound

Answer 3

SONAR (radar)
Pre-natal scans
Crack detection in metal

Question 4

What are the 2 types of seismic waves

Answer 4

S-waves
P-waves

Question 5

Describe P-waves

Answer 5

Longitudinal
Can travel through both solid and liquid rock
Provide useful information about the Earth’s core

Question 6

Describe S-waves

Answer 6

Transverse
Can only travel through solid rock
Travel in curved paths as they cant travel through the Earth’s molten core

Question 7

What is the law of reflection?

Answer 7

Angle of reflection = Angle of incidence

Question 8

What type of reflection happens at smooth surfaces?

Answer 8

Specular reflection (all rays reflected at same angle)

Question 9

What type of reflection happens at rough surfaces?

Answer 9

Diffuse reflection (rays are reflected at different angles)

Question 10

Why do light rays change direction when they enter a different medium at an angle?

Answer 10

Different parts of the wave front change medium at different times, slowing down at different times and hence changing direction

Question 11

What is a convex lens?

Answer 11

A lens that is thickr in the middle than at the edges
Parallel light rays that go through the lens converge at focal point

Question 12

What is a concave lens?

Answer 12

A lens that is thicker at the edges than in the middle
Parallel rays that go through the lens diverge

Question 13

What is focal length?

Answer 13

The distance from the middle of the lens to the focal point

Question 14

What is a real image?

Answer 14

Image formed an be seen on a screen

Question 15

What is a virtual image?

Answer 15

Image formed can only be seen by the person looking through the lens

Question 16

What is an upright image?

Answer 16

The image faces the same direction as the object

Question 17

What is an inverted image?

Answer 17

The image in the opposite direction to the object

Question 18

What is a diminished object?

Answer 18

The image is smaller than the object

Question 19

What is an enlarged object?

Answer 19

The image is larger than the object

Question 20

What equation is used for image magnification?

Answer 20

Magnification= Image height/Object height

Question 21

What is seperation of white light into the spectrum of visible colour?

Answer 21

Dispersion

Question 22

Which colour of light has the longest wavelength?

Answer 22

Red

Question 23

Which colour of light has the highest frequency?

Answer 23

Violet

Question 24

What makes an object appear white?

Answer 24

It reflects all wavelengths of light

Question 25

What makes a colour appear balck?

Answer 25

It absorbs all wavelengths of light

Question 26

How does a red filter work?

Answer 26

It absorbs all wavelengths of light except red It transmits red light

Question 27

All object emit radiation True or False?

Answer 27

True

Question 28

All object absorb radiation True or False?

Answer 28

True

Question 29

When do object heat up?

Answer 29

When the rate of energy absorption is higher than the rate of energy emission

Question 30

When do objects cool down?

Answer 30

When the rate of energy absorption is lower than the rate if energy emission