Learning Outcomes

- Identify different forces

- Describe the effects of balanced

and unbalanced forces

- Calculate the resultant force

Learning Outcomes

- Identify different forces

- Describe the effects of balanced

and unbalanced forces

- Calculate the resultant force

A New Hope

A New Hope

What is a forces?

Working in pairs

Forces

How many forces can you think of?

What forces are acting on you now?

Balanced and unbalanced forces

Equal forces acting on one object in opposite directions

Acceleration is zero

Speed is constant

(NO CHANGE IN MOTION)

Balance Forces

40N

40N

Balanced

Unbalanced Force

100N

40N

Forces are unequal

Unbalanced

All forces have direction

Forces change the speed and direction of movement

Force is measured in Newtons

Force is nearly almost push or a pull

Resultant Force

If two forces are unbalanced there is a resultant force.

It could replace all the others to give the same effect.

The difference between two forces is the resultant force.

The resultant force is 100N – 20N = 80N

Hint: work out the difference between the two forces.

100N

20N

Calculate the resultant force

10N

7N

5N

50N

200N

80N

105N

1N

Which direction does the box move?

1

2

4

3

**Well done everyone on your last assessment**

Fantastic work

Fantastic work

**The Empire Strikes back**

**Learning Outcomes**

• State what the speed equation is

•Use equation to work out the speed

•Be able to rearrange equation

•Describe factors that effect speed

• State what the speed equation is

•Use equation to work out the speed

•Be able to rearrange equation

•Describe factors that effect speed

**2. WHO WOULD NEED TO KNOW THIS?**

1. HOW DO YOU THINK WE CAN MEASURE SPEED?

Calculating Average Speed

average

speed

total distance

total time

Question 1

A group set off from home and walk at an average speed of 3.6 km/h. How far would they travel in two hours?

Give your answer in km.

Question 2

How long would it take a woman to walk 10 km if her average speed is 5.4 km/h ?

D

D

S

S

T

T

Rearranging the Equation

Homework

Worksheet -

Speed Equation

in for Tuesday

**Return of the Jedi**

**Learning Objective**

•Give some examples of factors that

affect friction

•Suggest ways of reducing friction

•Explain extra features such as spoilers

•Give some examples of factors that

affect friction

•Suggest ways of reducing friction

•Explain extra features such as spoilers

**What is Friction?**

Give examples when we use friction in application

How can we reduce friction?

Rub your hands together for a minute. How does that feel?

There is resistance to the rubbing motion.

The name of this resistant force is FRICTION

Friction can;

Produce heat

Wear things away

Slow things down

Make a noise

Friction is a ___________________ caused by two __________________ moving over each other. ___________________ surfaces produce more friction than __________________ surfaces.

Friction always tries to slow moving objects down. It opposes motion.

1. force 2. rough

3. smooth 4. surfaces

**The Phantom Menace**

Why do objects float?

Which item will float and which will sink?

Predict

Explain your prediction using scientific ideas

Where you correct?

Predict which of these items will float

1. Empty can of coke

2. Tennis ball

3. Book

4. Pencil

5. Brick

6. Boat

7. Full can of coke

8. You

Learning Objectives

**Attack of the Clones**

Learning Objective

- You must be able to explain the direction an object will move if the forces are unbalanced

- You should be able to measure how much force is acting on an object

- You could link how the amount of force to how much a spring stretches.

How much force pulls a spring down??

In compression the particles making up the material are pushed closer together

When it is under tension the particles making the material are pulled further apart

When a force is exerted on a spring it will either compress (push the spring together) or stretch the spring if the weight is hung on it.

Compression

Tension

Investigate how far a spring can stretch

What equipment do you need?

Make a prediction

What did you find out?

How could you improve

**Revenge of the Sith**

Learning Objective

Use a Newton meter

Describe what causes weight

Describe differences between mass and weight

Newton meter

The

MASS

of an object is a measure of how much “stuff” it contains”.

The

WEIGHT

of an object is the amount of force that pulls it downwards due to gravity.

This object has a MASS of 1Kg…

…and a WEIGHT of 10N

Record results in the table

Draw graph when finished

Where will the object move to?

**Why do you think this happened?**

Could you make a better bridge?

Learning Outcomes

• Identify the direction forces act in

• Use arrows on diagrams to represent direction of forces

• Make a series of observations about forces

Lockheed SR-71 Blackbird

The Peregrine Falcon

The Insano

The Cheeta

Usain Bolt

Hennessey Venom GT

The Venturi VBB-3

2193.2 mph

200 mph

65mph

70mph

27.79mph

265.7 mph

400 mph

Order from slowest to fastest

**On your white boards**

How can we work out the speed of The Big One?

Explain to theme park manager how they could work out the speed of The Big One

Describe factors that would show problems with calculating speed from just numbers.