ENERGY SOURCES. GRAVITY, FORCE & MOTION

Gravity :

it is a force that pulls objects toward each other. It’s what makes things fall to the ground when you drop them.

How does gravity work ?

Mass & Gravity , Distance & Gravity

Mass & Gravity :

The more massive an object is, the stronger its gravitational pull.

Distance & Gravity :

The closer two objects are to each other, the stronger the gravitational pull between them.

How does gravity work in space :

Planets & Orbits , Tides

Planets & Orbits

Gravity is what keeps the planets in our solar system orbiting around the Sun. The Sun’s gravity pulls on the planets, and the planets’ motion keeps them in orbit rather than falling into the Sun.

Tides :

The Moon’s gravity pulls on Earth’s oceans, causing the tides. When the Moon is directly overhead or on the opposite side of Earth, its gravitational pull causes the water to bulge out, creating high

Force :

A force is a push or a pull on an object. Forces can make things move, stop, or change direction. Forces can be strong or weak, & can act in different directions.

Types of forces :

Contact forces & non contact forces

Contact Forces :

These forces happen when two objects touch each other.

Friction :

This is the force that slows down or stops objects when they rub against each other.

Non~Contact Forces :

These forces act at a distance without the objects touching.

Applied force :

This is the force you apply to an object.

Which type of force does Gravity use ?

Non Contact Forces

Which type of force does Friction use ?

Contact Forces

Which type of force does Applied force use ?

Contact Forces

Magnetic Force

This is the force between magnets & magnetic materials.

Electric Force :

This is the force between charged particles.

How do forces affect motion?

Starting & Stopping, Changing Direction, Changing Speed

Starting & Stopping :

Forces can start or stop the motion of an object.

Changing Direction :

Forces can change the direction of an objects motion.

Changing Speed :

Forces can make objects speed up or slow down.

Balenced forces :

When forces on an object are equal and opposite, they cancel each other out, and the object doesnt move.

Unbalanced Forces :

When forces on an object are not equal, they don’t cancel out, and the object moves.

Motion :

It is the change in the position of an object over time. When something moves, it’s in it. It can be fast or slow, straight or curved, and it can change direction.

What are the types of motion :

Linear Motion, Rotational Motion, Periodic Motion, Random Motion

Linear Motion :

This is motion in a straight line.

Rotational Motion :

This is a motion around a central point.

Periodic Motion :

This is the motion that repeats at regular intervals.

Random Motion :

This is the motion that doesn’t follow a specific path.

Describing motion :

We often talk about speed, velocity , & acceleration.

Speed

This tells us how fast something is moving. It’s the distance an object travels in a certain amount of time.

Velocity :

This is similar to speed but includes the direction of motion.

Acceleration :

This is the change in velocity over time. If an object speeds up, slows down, or changes direction, it’s accelerating.

Force & Motion :

Forces causes motion. When you apply à force to an object , you can change its motion.

What are sir Isaac Newton’s famous 3 important laws of motion ?

Inertia

Force & Acceleration

3. Action & Reaction

Inertia :

An object at rest stays at rest, and an object in motion stays in motion unless acted on by a force.

Force & Acceleration

The of an object depends on the mass of the object and the amount of force applied.

Action & Reaction :

For every , there is an equal & opposite reaction.

How does gravity force & Motion work together ?

Gravity is a force that affects motion

Forces cause motion

Motion happens when forces act on an object

What’s an example of gravity ?

Imagine you have a ball. When you let go of it, gravity pulls it down to the Earth.

What does the strength of gravity depend on?

Thé mass of the objects & thé distance between them

Example of mass & gravity

Earth has a lot of mass, so it has a strong gravitational pull that keeps us on the ground. The Sun, which is much more massive than Earth, has an even stronger gravitational pull that keeps the planets in our solar system in orbit around it.

Example of Distance & Gravity

If you move farther away from Earth, the gravitational pull you feel becomes weaker.

Examples of forces :

pushing à door open, pulling a wagon , kicking à soccer ball

Example of contact forces

when you slide a book across a table, friction between the book and the table slows it down.

Example of magnectic force

a magnet can pull a paperclip towards it without touching it.

Example of electric force

static electricity can make your hair stand up when you rub a balloon on it.

Example of starting & stopping

kicking a soccer ball starts its motion, and friction with the ground eventually stops it.

Example of changing direction

when you hit a baseball with a bat, the force of the bat changes the direction of the ball.

Example of changing speed

when you pedal a bicycle, you apply a force that makes the bike go faster.

Example of balenced forces

if two people push on a box from

opposite sides with equal force, the box won’t move.

example of unbalanced forces :

if one person pushes a box harder than the other, the box will move in the direction of the stronger force.

Example of balenced & un balenced forces :

If both teams pull with equal force, the rope doesn’t move because the forces are balanced.

If one team pulls harder, the rope moves toward that team because the forces are unbalanced.

Example of motion :

À car driving down the street

À bird flying through the sky

À person running in à race

Example of linear Motion :

A car driving down à straight road or à ball rolling across the floor

Example of rotational Motion :

À spinning top or the earth rotating on its axis

Example of periodic Motion :

À swinging pendulum or a bouncing ball

Random Motion :

À butterfly flying around à garden

Example of speed :

If a car travels 70 kilometres in one hour, it’s blank is 60 kilometres per hour

Example of velocity

If a car is moving at 60km or h to the north, Thats it’s blank

Examples of forces & motion :

Pushing à swing : You apply à force that makes it move back and forth

Throwing a ball : you apply à force that makes it move through the air

Braking à bike : you apply à force that slows it down

Example of first law ( inertia ) :

À soccer ball won’t move until you kick it

Example of second law ( force & acceleration ) :

It’s easier to push an empty shopping cart than à full one because the empty cart has less mass

Example of 3rd law ( action & reaction )

When you jump off a boat, the boat moves in the opposite direction

Example of how gravity force & Motion work together

Gravity is when you throw a ball up in the air , it pulls it back down

Thé force of your makes the ball move

Motion is when the ball moves because of the force of your kick & the pull of the gravity

Example of how gravity force & Motion work together

When you slide down a slide, gravity pulls you down. When you push a swing, you’re applying a force to make it move. When you’re running around, you’re in motion because of the forces your legs create.