What do the following letters stand for?

SUVAT

How many equations can you remember using those variables?

Constant acceleration

• Know the 5 constant acceleration equations.• Understand how you can choose an equation

with the unknowns given• To be able to use them to solve problems

involving constant acceleration.

The constant acc. equations

S = displacement (m)U = initial velocity (m/s) (ms-1)V = final velocity (m/s) (ms-1)A = acceleration (m/s2) (ms-2)T = time taken (s)

The constant acc. equations

atuv 2

21 atuts

tvus 21

asuv 222

221 atvts

10 Quick Questions

10 Quick Answers

a)v= 11 b) s= 16 c) a= -1.5

d) s= 45 e) s= 102 f) a= 1.2

g) t= 14 h) t= 2.5 i) v= 24

j) a= -26.7

Question h

22935 tt 03592 2 tt

0355142 2 ttt 07572 ttt

0752 tt

7t5.2tQuadratic!

Doing SUVAT questions

1. For each question list the unknown values.2. Choose your equation.3. Substitute the values in.4. Solve to find the unknown.

Questions 6-10 require more thought!You will need to set up simultaneous equations.

Worksheet Answers

1) (a) 98m 2) (d) 16ms-1

3) (b) 0ms-2 4) (a) -2ms-1

5) (c) -0.3ms-2 6) (d) 4/75 ms-2

7) (a) 52/3 ms-1 8) (a) 2/3 ms-2

9) (d) 5/3 ms-1 10) (a) 25/12 m

Independent Study

Exercise E p22 (solutions p142) Mixed Questions p24 (solutions p142)

STARTER• 1. A parachutist jumps out of an aeroplane and

accelerates uniformly at 9.8 ms-2 for ten seconds. • a. How far does she travel? • b. What is her final velocity?• • 2. A car accelerates uniformly from 5 ms-1 to

20 ms-1 over a distance of 500m. • a. How long does this take? • b. What is the car’s acceleration?

Acceleration due to Gravity

• Know the links between speed, distance and time.

• To discuss vector and scalar terms.• To introduce vector notation

Acceleration due to Gravity• Famous scientist Galileo was probably

the first to look at how objects fall.• He noticed that objects fall

with a constant acceleration.• He also noticed that objects with a

different mass fall with the same acceleration.

• Legend has it that he tested this by dropping objects from the leaning tower of Pisa.

• The reason this is not always true on earth is due to air resistance.

• The theories of Galileo were tested on the moon landing mission.

• Moon Landing• Vacuum chamber

Acceleration due to Gravity

All objects, when dropped, fall towards the Earth in a vertical line with the same constant acceleration,

provided that there is no air resistance. (M1 always assumes no air resistance!)

The Value of “g”

• Acceleration due to gravity is denoted by the lowercase letter “g”

• It varies slightly across the Earth surface varying with latitude and altitude.

9.789ms-2

9.832ms-2

• The average value for g on Earth is 9.80665ms-2.• In maths we use an approximation for the

acceleration due to gravity to be g = 9.8ms-2

• Everywhere on Earth g = 9.8ms-2 when rounded to 2s.f.

• Other approximations then this will have a greater impact on our solutions.

The Value of “g”

Example 1

Dropping objectsA stone is dropped from rest at a height 10 metres above the ground. Find the velocity just before it hits the ground.

10m

t

msa

v

msu

ms

2

1

8.9

0

10asuv 222 114 msv

Example 2Objects Projected UpwardsA ball is thrown vertically upwards and rises a height of 10 metres. Find the speed with which it was thrown and the time it takes to return to the original height. 10

m

t

msa

v

u

ms

28.9

10a is now negative. Think about it, if you throw something up, it will slow to a stop. At the very top v = 0ms-1

Example 2To find speed, use the fact the final velocity

at top is v = 0.To find time, double the time it takes to reach

the top of its height.

10m

t

msa

v

u

ms

28.9

10 asuv 222 114 msu

atuv 43.1t

st 86.2

Have a go at the questions• Working in small groups answer each question.

• When you have an answer to a question get your answer checked then collect the next question.

• Make sure you work as a group and everyone is happy with the solution.

Exam Questions

Mark Scheme

Mark Scheme

Independent Study

Go to moodle and watch the videos on– Video 1 – Vectors Intro– Video 2 – SUVAT and Vectors