P2.1

Question 1

What apparatus is used to measure precise times e.g for a tennis ball falling?

Answer 1

Light gates

Question 2

How do you work out speed?

Answer 2

Distance / Time

Question 3

How many metres in a mile?

Answer 3

1609

Question 4

How many seconds in an hour?

Answer 4

3600

Question 5

How many orders of magnitude are between 5m/s and 123m/s

Answer 5

2

Question 6

What is the difference between vectors and scalars?

Answer 6

Vectors have a magnitude and direction,but scalar only has a magnitude

Question 7

If you walk in a circle at a constant speed,why does velocity change?

Answer 7

Velocity is vector so has a direction

If you walk in a circle you change direction,changing velocity

Question 8

If you run around a stadium to where you started, what is your displacement?

Answer 8

0m

Question 9

How do you work out velocity?

Answer 9

Displacement / Time

Question 10

What is acceleration?

Answer 10

The rate of change of speed/velocity

Question 11

How can you work out acceleration?

Answer 11

A = ( V - U ) / T

Change in velocity / time

Question 12

In what situation would something have a negative acceleration?

Answer 12

If it is slowing down

Question 13

On a distance time graph, where can you find speed?

Answer 13

The gradient of the graph

Question 14

What does a straight line on a distance time graph mean?

Answer 14

The speed is constant

Question 15

How do you work out velocity on a displacement time graph where there is a curve

Answer 15

Draw a tangent touching that point, and do change in displacement / change in time

Question 16

If there is a flat line on a distance time graph, what is the speed?

Answer 16

0m/s

Question 17

On a velocity time graph, what is the gradient equal to?

Answer 17

Acceleration

Question 18

How do you work out displacement from a velocity time graph?

Answer 18

Calculate the area underneath the graph

Question 19

How do you know if a graph is velocity time instead of speed time (without labels)

Answer 19

Velocity will have a positive and negative y axis

Question 20

How do you work out the acceleration of a trolley down a ramp?

Answer 20

Measure the length of the trolley
Use light gates at different points at the ramp,and they will measure how long the trolley takes to pass.
Do distance / time for speed at both/all gates
For change in speed use those speeds and for time use the difference in time between light gates.
Then do change in speed / time

Question 21

What is important to remember when writing units for acceleration

Answer 21

Its always unit squared

E.g m/s^2

Question 22

What are the equations of motion?

Answer 22

V^2 - U^2 = 2as - most important
V = U + at
s = 0.5(v + u) x t
S = ut + 0.5at^2
remember to rearrange when needed

Question 23

What is the equation for kinetic energy?

Answer 23

KE = 0.5 x mass x s^2 (speed in m/s)

Question 24

What is energy measured in?

Answer 24

Joules (J)

Question 25

If you double the speed how much is kinetic energy increased by?

Answer 25

4 , as in the equation speed is squared