Grade by Grade
D. Structures and Mechanisms · Simple Machines and Movement

Inclined Planes: Ramps

D2.3 D2.4 D2.5 A1.2 A1.5About 40 minutes
Learning goals
  • I can describe an inclined plane: a flat, slanted surface, like a ramp.
  • I can find inclined planes in daily life, like wheelchair ramps, slides and loading ramps.
  • I can measure and compare the force needed to lift something straight up and to pull it up a ramp.
  • I can explain that a longer, gentler ramp needs less force but a longer trip.

Words to know

inclined plane
A flat surface with one end higher than the other. A ramp is an inclined plane.
ramp
A slanted path that joins a low place and a high place.
steep
Slanted a lot, going up quickly. A steep hill is hard to climb.
gentle slope
Slanted only a little, going up slowly.
measure
To find out how long, how much or how big something is, using a tool like a ruler.

Up the steps or up the ramp?

Look at the front of a school, a library or a community centre. You will often see steps and also a long, slanted path called a ramp.

A person using a wheelchair, a parent with a stroller, or a delivery worker with a heavy cart cannot easily go up steps. But they can go up the ramp! A ramp is a simple machine called an inclined plane.

The front of a brick school with steps leading up to the doors and a long ramp with railings beside them.
The ramp is an inclined plane. It is longer than the steps, but it lets wheelchairs, strollers and carts roll up to the door. AI-generated image

What is an inclined plane?

An inclined plane is a flat surface with one end higher than the other. Inclined means slanted. Plane means a flat surface.

An inclined plane does not move. You move the load along it.

How does a ramp help?

Lifting a heavy box straight up onto a truck takes a big force. Pushing or pulling it up a ramp takes a smaller force. The box ends up just as high!

But there is a trade: you have to move the box a longer distance along the ramp.

liftpush up the rampramp = inclined plane
Lifting a box straight up takes a big force. Pushing it up the ramp (an inclined plane) takes a smaller force, but the trip is longer.

Steep or gentle?

Not all ramps are the same.

  • A short, steep ramp goes up quickly. It takes a bigger push.
  • A long, gentle ramp goes up slowly. It takes a smaller push, but you travel farther.

That is why wheelchair ramps are long and gentle. Roads that climb big hills or mountains often curve back and forth so they are not too steep.

short, steep rampharder pushlong, gentle rampeasier push, longer trip
Both ramps reach the same height. The long, gentle ramp needs a smaller push, but it is a longer trip.
Inclined planeHow it makes work easier
wheelchair ramppeople using wheelchairs, walkers or strollers can get into a building
loading ramp on a moving truckroll or push heavy furniture up instead of lifting it
boat launchback a boat on a trailer down into the lake instead of carrying it
slide at the parkyou slide down smoothly instead of jumping
curb cut at a crosswalkthe sidewalk slopes down to the road so wheels can roll across
Inclined planes in daily life
Worked example

Let's measure: lift it or ramp it?

We tie a rubber band to a toy car with some coins taped on top. We make a ramp with a board leaning on a stack of books. We measure how far the rubber band stretches.

  1. Question: Does a ramp make it easier to raise the car to the top of the books?
  2. Predict: I think pulling it up the ramp will need a smaller pull.
  3. Fair test: Same car, same coins, same rubber band, same height (the top of the book stack).
  4. Test 1: Lift straight up. Hold the rubber band and lift the car up beside the books. The band stretches 10 cm.
  5. Test 2: Long, gentle ramp. Pull the car slowly up a long board. The band stretches 3 cm.
  6. Test 3: Short, steep ramp. Use a shorter board to the same height. The band stretches 7 cm.
  7. Compare: 3 cm is the smallest. The long, gentle ramp needed the smallest pull.

Both ramps needed less force than lifting straight up. The long, gentle ramp needed the least force, but the car travelled the farthest. (Your numbers will be different, but the pattern should be the same.)

Just for fun

What did the playground slide say to the kids?

"Don't worry, I'll always let you down... gently!"

How we raised the carRubber band stretch
lifted straight up10 cm
short, steep ramp7 cm
long, gentle ramp3 cm
Our results. A bigger stretch means a bigger force.
Hands-on activity

Rubber band ramp test

You need: a toy car, a few coins and tape, a rubber band, string, a ruler, a stack of books, and two flat boards or stiff pieces of cardboard (one long, one short).

  1. Tape the coins on top of the car. Tie the string to the car and loop the rubber band onto the string.
  2. Stack books about as high as your ruler is long.
  3. Lift the car straight up to the top of the books by holding the rubber band. Measure the stretch with the ruler.
  4. Lean the long board on the books. Pull the car slowly up. Measure the stretch.
  5. Lean the short board on the books. Pull the car slowly up. Measure the stretch.
  6. Make a results chart. Circle the smallest stretch.
  7. Share: Tell a grown-up which way needed the least force and why.

Safety: Keep the book stack steady and low. Don't let the rubber band snap toward anyone.

Your turn

1

What is an inclined plane?

2

Is it easier to lift a heavy box onto a truck or to push it up a ramp?

3

What is the trade when you use a ramp?

4

Which needs a smaller push: a long, gentle ramp or a short, steep ramp?

5

Why do many schools and libraries have a ramp beside the steps?

6

Name an inclined plane at the playground.

7

In our test, lifting stretched the band 10 cm and the long ramp stretched it 3 cm. How much smaller was the ramp's stretch?

More practice: warm-up

1

Is a ramp an inclined plane?

2

Does an inclined plane move when you use it?

3

What does "steep" mean?

4

Name one place you have seen a ramp.

5

Which is harder to walk up: a steep hill or a gentle hill?

More practice: on your own

1

Movers use a ramp to put a fridge into their truck. How does the ramp help them?

2

Why are wheelchair ramps long and gentle, not short and steep?

3

In a fair ramp test, what must stay the same?

4

A rubber band stretched 6 cm on Ramp A and 2 cm on Ramp B. Which ramp is probably longer and gentler?

5

Why do roads up a big mountain curve back and forth?

Challenge

1

Ramps A and B both go up to the same porch. Ramp A is 2 metres long. Ramp B is 6 metres long. Which needs less force to push a wagon up? Which trip is longer?

2

Your town is building a new library with only steps at the door. Write a short note explaining why it needs a ramp too.

3

Is a slide an inclined plane even though you go down it, not up? Explain.

Check your understanding

Quiz

1.

An inclined plane is...

2.

Pushing a box up a ramp takes ___ force than lifting it straight up.

3.

Which ramp needs the smallest push to the same height?

4.

Which is an inclined plane?

5.

In a rubber band test, a bigger stretch means...

6.

What is the trade when you use a ramp?

For parents and teachers

Big idea: An inclined plane (ramp) is a flat, slanted surface that lets you raise a load with less force than lifting it straight up, over a longer distance (D2.3, D2.4). The rubber band test is a quantitative comparison of force, measured in centimetres (D2.5), done as a fair test (A1.2) and shared in a chart (A1.5).

How to help: Notice ramps in your community: at school, the library, stores, curb cuts, moving trucks. Talk about who they help. This connects to the next lessons on how simple machines affect people's lives.

Common difficulties:

  • Thinking a ramp makes the load lighter. The load weighs the same; the ramp spreads the work over a longer distance.
  • Reading the ruler. Help your child line the ruler up with the rubber band's resting length and read where it stretches to.
  • Unfair test. Make sure both ramps reach the same height.