Chapter 2

Question 1

Acceleration

Answer 1

Rate of change of velocity

Question 2

Straight line in v-t graph

Answer 2

Constant acceleration

Question 3

Steeper slope in v-t graph

Answer 3

Greater acceleration

Question 4

Gradient is 0 in v-t graph

Answer 4

Velocity is constant

Acceleration is 0

Question 5

Negative slope in v-t graph

Answer 5

Deceleration

Question 6

Changing slope in v-t graph

Answer 6

Acceleration is changing

Question 7

Gradient of v-t graph and

Area of v-t graph

Answer 7

Acceleration and

Displacement

Question 8

What measures velocity and acceleration

Answer 8

Accelerometer

Question 9

Using light gates to determine velocity and acceleration

Answer 9

Calculate initial and final acceleration:
u = L1/T2-T1
v= L2/ T4-T3
a = v-u/t3-t1

Question 10

Using ticker-timer to determine velocity and acceleration

Answer 10

Dots at certain interval represent time interval
Length of interval in cm is displacement
Gradient is the acceleration

Question 11

Equation 1 of equations of motion

Answer 11

V = u + at

Question 12

Equation 2 of equations of motion

Answer 12

S = (u+v)/2 x t

Question 13

Equation 3 of equations of motion

Answer 13

S = ut + 1/2at^2

Question 14

Equation 4 of equations of motion

Answer 14

V^2 = u^2 + 2as

Question 15

When the equations of motion be used

Answer 15

For motion in a straight line

For an object with constant acceleration

Question 16

Deriving equation 1 of the equations of motion

Answer 16

a = v-u/t

Make v the subject

Question 17

Deriving equation 2 of the equations of motion

Answer 17

Avg velocity = U+v/2
Displacement = avg velocity x time
S= u+v/2 x t

Question 18

Deriving equation 3 of the equations of motion

Answer 18

Equation 1: V = u + at
Equation 2: S = u+v/2 x t
Sub v from equation 1 into equation 2

Question 19

Deriving equation 4 of the equations of motion

Answer 19

Equation 1: v = u + at 
Equation 2: s = u+v/2 x t 
Sub t from equation 1 
Find lcd and multiply 
Make v^2 the subject

Question 20

How to find acceleration on a graph

Answer 20

Mark a point on the graph at time of interest
Draw a tangent to the curve at that point t
Make a right angled triangle to find gradient

Question 21

How to find acceleration caused by gravity

Answer 21

Acceleration of free fall 
V = 0 
Sub into s = ut + 1/2at^2 
Plot on a graph 
Find gradient 
Gradient = t^2 
t^2 = g/2 
g= 0.84/0.20 x 2

Question 22

How to find using a light gate

Answer 22

Find acceleration from initial and final velocity

Question 23

Component vectors

Answer 23

Y: cos
X: sin

Question 24

How to calculate the height of projectile

Answer 24

V^2 = U^2 + 2as 
Acceleration is negative 
U is known 
V is zero 
Find a

Question 25

How to find time of a projectile

Answer 25

s= it + 1/2at^2 
s=0
u is known 
G Acceleration is negative 
Find t

Question 26

How to find the final displacement after falling a cliff

Answer 26

Displacement is negative

Use s = ut

Question 27

The horizontal and vertical motion of a projectile and distance fallen

Answer 27

Horizontal: distance increase because unaffected by gravity so v = s/t
Vertical: accelerating downwards
Horizontal distance = v x t
Vertical distance: u = 0 so use s= ut

Question 28

How to find the time of a projectile thrown horizontally

Answer 28

Find for both vertical and horizontal planes: 
Find horizontal and vertical velocity
Find time: 
S = ut 
U= 0 
Calculate t^2
Distance travelled: 
Distance travelled = u x t

Question 29

How to find the range of a projectile

Answer 29

Velocity: 
Horizontal and Vertical components initial velocity 
Time: 
s = ut 
Horizontal displacement 
s = v x t