Unit 2

Question 1

What is a vector quantity?

Answer 1

Has magnitude and direction

Question 2

Give an example of a scalor quantity

Answer 2

Distance, speed, time, power, etc.

Question 3

Give an example of a vector quantity

Answer 3

Displacement, velocity, acceleration, force

Question 4

What is displacement?

Answer 4

The direct distance from start to end

Question 5

What is speed?

Answer 5

The distance traveled per unit time

Question 6

What is velocity?

Answer 6

The displacement per unit time

Question 7

To find a resultant force what would be used?

Answer 7

Pythagoras and trigonometry

Question 8

Vectors can be combined to produce what?

Answer 8

A resultant vector

Question 9

What is acceleration?

Answer 9

The change in velocity per unit time

Question 10

What causes an object to accelerate when dropped?

Answer 10

An unbalanced force

Question 11

Ignoring friction do all objects in free fall accelerate at the same rate?

Answer 11

Yes

Question 12

On a velocity time graph, how is displacement calculated?

Answer 12

Area of each shape is found then added together

Question 13

What is the unit of force and how can it be measured?

Answer 13

Newtons (N), using a Newton balance

Question 14

When does a balanced force occur?

Answer 14

When an object has equal sized forces acting in opposite direction

Question 15

What happens to the motion of an object when the forces are balanced?

Answer 15

Will be at rest or traveling in a straight line at a constant velocity

Question 16

What happens to the motion of an object when the forces are unbalanced?

Answer 16

Object will be accelerating or decelerating

Question 17

An object falling at terminal velocity will have what kind of forces acting on it?

Answer 17

Balanced forces. Weight down will balance with air resistance upwards

Question 18

When does an unbalanced force occur?

Answer 18

When an object has forces acting on it that do not cancel each other out

Question 19

When does friction occur?

Answer 19

When two surfaces are in contact while moving past each other

Question 20

What is a scalor quantity?

Answer 20

Quality that only has magnitude

Question 21

How can friction be reduced?

Answer 21

If the surface contact area is reduced or surface is smoother

Question 22

When friction acts between surfaces what types of energy are there?

Answer 22

Kinetic energy is transformed into heat energy

Question 23

What is Newton’s first law?

Answer 23

An object will remain at rest or remain at a constant velocity unless acted on by an unbalanced force

Question 24

What is Newton’s second law?

Answer 24

The acceleration of an object is directly proportional to the unbalanced force and inversely proportional to the mass of an object

Question 25

What is Newton's third law?

Answer 25

If object A exerts a force on object B, then object A exerts an equal but opposite force on object A

Question 26

What is mass?

Answer 26

The amount of matter in an object

Question 27

What is weight?

Answer 27

The force on an object caused by the force of gravity

Question 28

What is work done?

Answer 28

An amount of energy being transferred

Question 29

When is a object a projectile?

Answer 29

If it has both vertical and horizontal motion

Question 30

What happens to the vertical and horizontal motion in a projectile?

Answer 30

Horizontal velocity is constant. Vertical velocity is increasing

Question 31

As the height (altitude) of a satellite increases, what happens to the period?

Answer 31

It increases

Question 32

What are some uses of satellites?

Answer 32

Telecommunications, weather forecasting, satnav

Question 33

How does a rocket take off in terms of forces and motion?

Answer 33

If the up thrust force remains constant, the unbalanced force increases and acceleration increases

Question 34

When a space craft re enters Earth's atmosphere, what does friction cause?

Answer 34

It transforms kinetic energy into heat energy

Question 35

If the angle of re-entry is too steep what happens to the spacecraft?

Answer 35

Drag force is too large, too much heat and space craft is destroyed

Question 36

If the angle of re-entry is too shallow what happens to the spacecraft?

Answer 36

Drag force is too small, spacecraft returns to orbit

Question 37

What is used to protect spacecrafts during re entry?

Answer 37

Silica tiles?

Question 38

Why are silica tiles used to protect spacecrafts?

Answer 38

They have a high melting point, good insulators, will remain a constant temperature as they melt. Painted black to radiate heat

Question 39

What is specific latent heat?

Answer 39

The heat energy needed to change the state of 1kg of material

Question 40

What is specific latent heat of vaporisation used for?

Answer 40

The change between liquid and gas

Question 41

What is specific latent heat of fusion used for?

Answer 41

The change between a liquid and a solid

Question 42

What type of energy is either absorbed or released when a material changes state?

Answer 42

Heat energy

Question 43

What can be used to identify elements present within stars?

Answer 43

Spectra

Question 44

Where does a continuos spectrum come from?

Answer 44

A hot white light source

Question 45

Where does a line spectrum come from?

Answer 45

A hot gaseous element. Shows frequencies on a black background

Question 46

What is a light year?

Answer 46

The distance light travels in one year

Question 47

What is one light year?

Answer 47

9.47 x 10^15 m

Question 48

What does a continuous spectrum contain?

Answer 48

All the wavelengths (colours) of light