8+9 revision

Question 1

What properties do vectors have?

Answer 1

magnitude and direction

Question 2

What properties do scalars have?

Answer 2

Just magnitude, no direction

Question 3

Is energy a vector or a scalar?

Answer 3

scalar

Question 4

Is power a vector or a scalar?

Answer 4

scalar

Question 5

Is force a vector or a scalar?

Answer 5

vector

Question 6

Is weight a vector or a scalar?

Answer 6

vector

Question 7

What is velocity?

Answer 7

speed in a particular direction

Question 8

What is the formula for (average) velocity?

Answer 8

displacement/ time taken

Question 9

What is the formula for (average) speed?

Answer 9

distance/ time taken

Question 10

What is the relative velocity when two objects move in opposite directions?

Answer 10

The sum of the magnitudes of both velocities

Question 11

What is the relative velocity when two objects move in the same direction

Answer 11

The difference between the magnitudes of the two velocities

Question 12

How do you find the relative velocity of two objects?

Answer 12

Add the opposite of one velocity to both velocities. The resultant velocity not zero is the relative velocity.

Question 13

What is the area under a velocity time graph?

Answer 13

The distance travelled

Question 14

What happens when three forces acting on an object are in equilibrium?

Answer 14

The vectors form a closed triangle when added tip to tail

Question 15

What is Newton’s first law?

Answer 15

An object will move at a constant velocity unless acted upon by an external force

Question 16

What is Newton’s second law?

Answer 16

sum of forces = mass x acceleration

F=ma

Question 17

What is Newton’s third law?

Answer 17

Every action has an opposite and equal reaction

Question 18

How do you resolve a vector?

Answer 18

Split it into its horizontal and vertical components

Question 19

When are suvat equations used?

Answer 19

When there is an acceleration and it is constant

Question 20

What are the suvat equations?

Answer 20

v^2 = u^2+2as
v=u+at
s=ut + 1/2at^2
s=1/2(u+v)t

Question 21

For which component is suvat used for projectiles?

Answer 21

The vertical (this is where acceleration happens)

Question 22

When is the velocity 0 in the flight of an object?

Answer 22

At the top of the flight

Question 23

When is work done?

Answer 23

When a force moves its point of application

Question 24

What is the formula for work?

Answer 24

force x distance moved in direction of force

W=Fs

Question 25

What is kinetic energy?

Answer 25

The energy an object has because of its motion and mass

Question 26

What is the formula for kinetic energy?

Answer 26

1/2 x mass x v^2

v=speed not velocity in this equation

Question 27

What happens to an object’s energy when it falls?

Answer 27

Its gravitational potential energy is transferred to kinetic energy

Question 28

What is the formula for work done against gravity?

Answer 28

mgh

h = change in height

Question 29

What is power?

Answer 29

The rate of transfer of energy

Question 30

What are the units of work?

Answer 30

joules

Question 31

What are the units of power?

Answer 31

watts

Question 32

What are the formulae for power?

Answer 32

energy transferred/time
work done/time
force x velocity

Question 33

What is kinetic energy gained/lost?

Answer 33

force x displacement

Question 34

What is work done (in terms of kinetic energy)?

Answer 34

the change (loos/gain) in kinetic energy

Question 35

What is energy?

Answer 35

The capacity to do work

Question 36

What are the units of energy?

Answer 36

joules

Question 37

How is the instantaneous velocity found from a distance time graph?

Answer 37

The tangent