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READING 2 Answer the questions. Work with a partner.
1. What is the first thing you do when you sit in a roller coaster?
1 Listen and read. TR: 9.8 2. How do you feel when you go fast down the hill?
Up, Down, and All Around! 3. How do you feel when you go fast up the loop the loop?
4. Why do some people feel dizzy or sick on roller coasters?
You are going on a roller-coaster ride. Sit in the car and pull down the safety
bar. Are you ready? Let’s go! 3 Complete the chart. Work with a partner. When do you
First you go up a steep hill. The roller coaster goes slow. Next gravity pulls you experience these forces in roller coasters and on bicycles?
down the hill. The roller coaster moves fast. You feel very light!
Roller coaster Bicycle
A big circle, known as the “loop the loop,” is many people’s favorite. When you
go fast up the circle, you feel heavy. Gravity is pulling you down. When you reach
the top, you are high in the sky. And you’re hanging upside down! So why don’t you Gravity
fall out of your seat? Your body wants to fly off, but the speed of the car and a force
called centripetal force keep you moving in a circle, and keep you in your seat!
The roller coaster uses friction to stop. If it stops quickly, your body wants to
continue moving. That is called inertia. But the safety bars keep you in place! Centripetal force
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Not everyone loves roller coasters. They make some people feel dizzy or sick
because the forces change. In fact we experience forces like friction, centripetal
force, and gravity every day. For example you feel gravity when you jump Friction
with your bike and come down. You feel centripetal force when you turn,
and you feel friction when you use the brakes to stop the bike.
How do you want to experience the forces? Do you want to ride
your bicycle or a roller coaster? Inertia
Russians invented the roller coaster. They
made the “cars” from ice. And they put straw 4 Look and discuss. Work with a partner.
on the seats to keep the passengers warm.
Describe a ride on a roller coaster.
What does the roller
coaster look like?
It looks like a spaceship!
What happens first?
You go straight toward a
moon, but then you turn!
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