4. unbalanced forces

Post on 13-Apr-2017

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Transcript of 4. unbalanced forces

Hello again!

UNBALANCED FORCES

By: JINKY N> ORAIZ

1. Do all forces result in movement?

2. What do you think is the net force in

the example below?

3. Why?

LET’S RECALL! Balanced

Forces

NO!

ZERO!

Because the acting forces are equal and in opposite direction and there is no movement!

Kids, DON’T do this at home or anywhere!!!

WARNING!

Does the example below show

balanced forces?

Weight of the boat with people

pulling down (gravity)

Water pushing up the boat (buoyancy/resistance)

LET’S RECALL!

YES

What do you think could happen if the

forces acting here will be unequal?

Consider this!

The boat will sink!Which is very dangerous to passengers.

Consider this!

So, what is meant by

unbalanced forces?

the two interacting forces are not equal, so that there is a movement in one direction.

Examine this tug of war.  Each person can pull with exactly (1) force.

1. What is the force for the team on the left side?  

2. What is the force for the team on the right side?

3. Which direction will the rope move?

3 forces2 forces

To the left

3 forces 2 forces

1. What forces are interacting here?  

2. Which has greater force?

3. How can you tell?

Because the car moves towards the direction of the tires’ rotation.

Car’s tires rotating towards right Friction from the ground opposing the tires

Examine the moving car.

Balanced or Unbalanced Forces?TRY THIS!

Unbalanced

Balanced or Unbalanced Forces?TRY THIS!

Balanced

Balanced or Unbalanced Forces?TRY THIS!

Unbalanced

The Hippo Jump

Suppose, a hippo jumps from a

flying airplane, which direction will the hippo

moves?

Because of the pull (force)

of gravity

Why?

The Hippo Jump

How can we save the hippo?

The Hippo Jump

How can we save the hippo?

The Hippo Jump

Open the hippo’s

parachute!

Saved?Will the hippo continue to move?

Which direction will the hippo move?

Yes! Heeeelllp!

Hippo is still falling quickly

but not getting faster

force of gravity

force of air (air resistance)

How do we know?

Questions?

Unbalanced Forces

QUIZ TIME!

2. Draw and label the arrow of the

interacting forces.

1. Balanced or Unbalanced

Forces?

force of gravity

Force of air (air resistance)

3. How can we slow

“hippo” down?

Hippo is still falling quickly

but not getting faster

Let’s CHECK

Your Answers….

2. Draw and label the arrow of the

interacting forces.

1. Balanced or Unbalanced

Forces?

Unbalanced forces

Thrust of rocket engines

Pull of gravity

force of gravity

air resistance3. How can we slow

“hippo” down?Answer:

Increase air resistance by

giving “hippo” a bigger or

larger parachute.

ASSIGNMENT:Suppose, Superman and Hulk are pulling a truck at

the same time with 20 units of force each. What is

the net force acting on the object?

That’s all for today… more forces coming next…