Anh 10 - Bài 3- issac newton (mai anh)

Astronauts orbiting the earth don’t have weight.. Other bodies in the universe have a pull just as the earth does.. The pull of the earth is called gravity... The pull of the earth is ca

Who is he?

What did he discover?

When did he discover the law of gravity ?

Isaac Newton the law of gravity

UNIT 3

GRAVI

TY

VOCABULARY

PLANET

A ROCKET

Take off

SPEED escape from

A man-made satellite

Float about

ASTRONAUT

= spaceman

Space capsule / space ship

Space suit helmet

Weightless (adj)

Weightlessness (n)

Space flight

Anchor (v)

Do you agree or disagree?

1 Gravity pull everything down

2 A champion high jumper can jump more than ten feet

off the ground

3 As the earth whirl around, everything is thrown off the

earth

4 Man-made satellites leaves the earth at very great

speeds

5 Every person has a weight on the earth

6 Astronauts orbiting the earth don’t have weight

7 Weightlessness is a big problem

8 Other bodies in the universe have a pull just as the

earth does

9 The sun exerts a pull on other planets in its system

Even a high jumper can jump only about

seven and a feet off the ground The earth pulls him so hard that he cannot jump any higher The pull of the earth is called gravity

How high can a high jumper jump?

He can jump only about seven and

a half feet off the ground.

Why can’t he jump higher?

Because the earth pull him very hard.

What do you call the pull of the earth?

The pull of the earth is called gravity.

Gravity makes water run downhill It makes balls thrown into the air fall back down, and ripe apples drop from trees

Gravity keeps us all from being hurled off the earth as it whirls around It keeps the moon travelling around and around the earth instead of shooting off into space.

What would happen if there were not gravity?

If there were not gravity,

Water wouldn’t run down hill.

Ball thrown into the air wouldn’t fall back down Ripe apple wouldn’t drop from trees.

We would be hurled off the earth.

The moon would be shot into space.

Some man-made satellites have escaped from the earth and gone into outer space never to return But to do so they had to take off from the earth at a speed of more than 25,000 miles an hour.

Can man-made satellites escape from the earth? Yes, it can.

How can they escape from the earth?

They had to take off from the earth at a speed of more than 25,000 miles

an hour.

1km = 0.6214mile 25,000 miles ≈ 40,231km

1foot = 30.48 cm  7.5 feet = 228.6cm ≈ 2.28m

A person can easily find out how hard the earth is pulling him All he has to do is weigh himself If there weren’t gravity,

no one would weigh anything at all.

Can a person find out how hard the earth is puling him? How?

Yes, he can He can weigh himself.

What would happen if there were not gravity?

No one would weigh anything at all.

Astronauts orbiting the

earth in space capsules are weightless Before

anyone had made a

space flight, scientists

wondered whether a

person could stand

weighing nothing Actually weightlessness has been

no problem except for the nuisance of having to

anchor every object in a space capsule in place to keep it from floating

about

Do astronauts in space capsules have a weight?

No, they don’t They are weightless.

Is weightlessness a big problem?

No, it isn’t but they have to anchor every object in a space capsules in place to keep it from floating about.

All other bodies in the universe exert a pull just as the earth does The pull of the sun keeps its whole family of planets from

running away.

What do all the bodies in the universe exert?They exert a pull of the sun to keep its whole family of the planets from running away.

Do you agree or disagree?

1 Gravity pull everything down

2 A champion high jumper can jump more than ten feet

off the ground

3 As the earth whirl around, everything is thrown off the

earth

4 Man-made satellites leaves the earth at very great

speeds

5 Every person has a weight on the earth

6 Astronauts orbiting the earth don’t have weight

7 Weightlessness is a big nuisance

8 Other bodies in the universe have a pull just as the

earth does

9 The sun exerts a pull on other planets in its system

Even a high can jump only about seven and a half feet off

him so hard that he cannot jump

any higher The pull of the earth is

jumper

gravity

Gravity makes water run

It makes balls into the air fall back down, and ripe

hurled off the earth as it whirls

It keeps the moon around and around the earth instead of shooting off

space.

into travelling

around

from from

thrown downhill

Some satellites have escaped from the earth

to return But to do so they had

speed of more than 25,000

man-made

space take off

hour

A person can easily find out how

All he has to do is

himself If there weren’t ,

no one would weigh anything at all.

earth

weigh

gravity

Astronauts orbiting the earth in

are weightless

Before anyone had made a , scientists wondered whether a person could stand weighing

Actually has been no problem except for the nuisance of

having to anchor every object in a

in place to keep it from floating

space capsules

space flight

nothing weightlessness

space capsule

about

All other bodies in the

exert a pull just as the

does The pull of the sun keeps its whole family

from running away.

universe

earth planets

GOOD BYE!