# Air Resistance 2

In this worksheet, students will be helped to explore the effect of air resistance on a variety of objects in a range of situations so that they can put it into the context of forces as a whole.

Key stage:  KS 2

Curriculum topic:   Forces

Curriculum subtopic:   Resistance and Friction

Difficulty level:

### QUESTION 1 of 10

Air resistance is the force of the air pushing against objects. It might be the wind blowing against a tree or it might be caused by the object, like a lorry, moving through the air.

As you go through this worksheet think about how easily air is pushed out of the way by an object and how big the force of air resistance might be, pushing against the object - even though air is invisible!

Air resistance is a force that is mainly caused by what?

friction

gravity

wind

Modern car designers make sure that cars are shaped so that they are as slippery as possible - at least, slippery through the air! What is this slippery sort of shape better known as?

smooth

streamlined

sleek

In the popular TV series 'Star Trek', the spaceships of a group of aliens called The Borg looked like this:

These cubes are not slippery at all. Why do you think they could still go very fast?

they have powerful engines

they are made of a slippery material

there's no air resistance in space

The last space shuttle, Atlantis, landed at Kennedy Space Centre on 8 July 2011. When space shuttles re-enter Earth's atmosphere from space they glow red hot underneath.

Why do you think this is?

from the sheer speed that the shuttle is travelling at

this is heat from the after-burners

this is caused by friction with the air

Some plant seeds use air resistance to help them fall slowly at the same time as they are being blown away from the plant from where they were released.

Which one of these seeds do you think is designed to fall slowly using air resistance and not to be blown miles away?

 SYCAMORE ACORN DANDELION BLACKBERRY BURDOCK
Sycamore

Acorn (Oak)

Dandelion

Blackberry

Burdock

Mr. Young's class is investigating how fast feathers fall to the ground.

He gives his class two sorts of feather:

 BIG FEATHER SMALL FEATHER

Then he asks for their ideas about how long it is likely to take each one to fall to the ground.

Alfie said: "the big feather will fall fastest as it's heavier."

Oliver said: "the small feather will fall more slowly as it catches the air better."

Megan said: "the big feather will fall more slowly as there are more feathery bits."

Whose prediction do you agree with most?

Alfie

Oliver

Megan

Mr. Young asked his class what they needed to keep the same so that their test was fair.

The young scientists made a variety of suggestions; tick the ones you think are important.

drop each feather the same number of times

drop each feather at the same time

drop them from the same height

make sure the same person drops it each time

Apart from young scientists and feathers, what else do you think is necessary to carry out this investigation (choose only one)?

stopwatch

metre ruler

scissors

Here are the class's results:

BIG
FEATHER

SMALL FEATHER
Time to fall/sec 2 8

Elliot said: "The big feather took 2 seconds to fall while the small feather took 8 seconds to fall."

Tami said: "The big feather took less time to fall than the small feather."

Alisha said: "The small feather fell slower because it's light and more feathery."

Who do you think tried to explain the results rather than simply describing them?

Elliot

Tami

Alisha

What do you think is the most important reason for the small feather falling more slowly than the big feather?

it's lighter

it's curved

it's less streamlined

• Question 1

Air resistance is a force that is mainly caused by what?

friction
EDDIE SAYS
Air is made of tiny, tiny particles - billions of them - that have to be pushed out of the way in order to move through it - that causes friction: rubbing of the air particles against the object.
• Question 2

Modern car designers make sure that cars are shaped so that they are as slippery as possible - at least, slippery through the air! What is this slippery sort of shape better known as?

streamlined
EDDIE SAYS
Cars are much more STREAMLINED today than in days gone by - another way of expressing this is that they are AERODYNAMIC. That means the air moves over them more easily so they use less fuel to move through the air; very important in today's energy-conscious world.
• Question 3

In the popular TV series 'Star Trek', the spaceships of a group of aliens called The Borg looked like this:

These cubes are not slippery at all. Why do you think they could still go very fast?

there's no air resistance in space
EDDIE SAYS
In space there's no air, so nothing to push out of the way, nothing to slow you down, so a streamlined shape makes no difference in terms of going faster.
• Question 4

The last space shuttle, Atlantis, landed at Kennedy Space Centre on 8 July 2011. When space shuttles re-enter Earth's atmosphere from space they glow red hot underneath.

Why do you think this is?

this is caused by friction with the air
EDDIE SAYS
Even though there is much, much less air at the top of the atmosphere, it's still an awful lot more than no air at all; so when a shuttle travelling at 20 000mph re-enters the atmosphere from space, the friction caused by all those air particles creates a terrific amount of heat.
• Question 5

Some plant seeds use air resistance to help them fall slowly at the same time as they are being blown away from the plant from where they were released.

Which one of these seeds do you think is designed to fall slowly using air resistance and not to be blown miles away?

 SYCAMORE ACORN DANDELION BLACKBERRY BURDOCK
Sycamore
EDDIE SAYS
Sycamore seeds work like helicopters, whirling around as they float down, using air resistance to slow their descent. Dandelion seeds are light and will be blown a long way on the wind. Acorns and blackberries are heavy and burdock seeds catch in mammals' fur to be carried away.
• Question 6

Mr. Young's class is investigating how fast feathers fall to the ground.

He gives his class two sorts of feather:

 BIG FEATHER SMALL FEATHER

Then he asks for their ideas about how long it is likely to take each one to fall to the ground.

Alfie said: "the big feather will fall fastest as it's heavier."

Oliver said: "the small feather will fall more slowly as it catches the air better."

Megan said: "the big feather will fall more slowly as there are more feathery bits."

Whose prediction do you agree with most?

Oliver
EDDIE SAYS
Heavier things don't actually fall faster. The small feather creates more resistance to the air because of its shape so it will take longer to push the air out of the way. If you don't believe that take two identical pieces of paper, scrumple one up into a ball and drop them at the same time - the flat one will always take longer to float to the ground as it has more area to create air resistance.
• Question 7

Mr. Young asked his class what they needed to keep the same so that their test was fair.

The young scientists made a variety of suggestions; tick the ones you think are important.

drop each feather the same number of times
drop them from the same height
EDDIE SAYS
To make it fair both feathers must start at the same height and both must be dropped the same number of times. In an ideal world it would be the same person but in a class of young scientists there would be a cry of "that's not fair", so there we are! They don't need to be dropped at the same time - it makes no difference.
• Question 8

Apart from young scientists and feathers, what else do you think is necessary to carry out this investigation (choose only one)?

stopwatch
EDDIE SAYS
The young scientists have to be able to time accurately how long it takes each feather to reach the ground after it's been released, so a stopwatch is vital. A metre ruler might be a good idea but as long as the feather's released from the same place (like level with a shelf) it isn't necessary.
• Question 9

Here are the class's results:

BIG
FEATHER

SMALL FEATHER
Time to fall/sec 2 8

Elliot said: "The big feather took 2 seconds to fall while the small feather took 8 seconds to fall."

Tami said: "The big feather took less time to fall than the small feather."

Alisha said: "The small feather fell slower because it's light and more feathery."

Who do you think tried to explain the results rather than simply describing them?

Alisha
EDDIE SAYS
Both Elliot and Tami simply stated what the results showed: the small feather fell more slowly. Alisha had a go at explaining why this result might have happened.
• Question 10

What do you think is the most important reason for the small feather falling more slowly than the big feather?

it's less streamlined
EDDIE SAYS
As you\'ll learn, heavy things don\'t fall faster than light things; in fact an experiment with a feather was tried on the moon: an astronaut dropped a hammer and a feather at the same time and guess what? They hit the moon\'s surface at the same time! The reason the feather falls so much more slowly here is simply air resistance: it\'s shape is bad at pushing air out of the way, so it takes a long time to fall.
---- OR ----

Sign up for a £1 trial so you can track and measure your child's progress on this activity.

### What is EdPlace?

We're your National Curriculum aligned online education content provider helping each child succeed in English, maths and science from year 1 to GCSE. With an EdPlace account you’ll be able to track and measure progress, helping each child achieve their best. We build confidence and attainment by personalising each child’s learning at a level that suits them.

Get started