Between Floors

Ride inside a cutaway lift and investigate its hidden connections: the counterweight, gripping ropes, moving pulleys, door locks and brakes. Explain what changes when people board, the car speeds up or power disappears. Seven investigations for ages 12 and up.
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Course cover

Heavy and Light

Lesson 1
An Empty Lift Is Still Heavy image

An Empty Lift Is Still Heavy

An empty lift is heavy. How can its motor make electricity while lifting it upstairs?
Start
Lesson 2
The Moment Your Knees Notice image

The Moment Your Knees Notice

Why do you feel heavier for a moment when a lift starts moving up?
Start

Rope and Wheel

Lesson 3
The Rope That Is Not Tied On image

The Rope That Is Not Tied On

The ropes holding a lift wrap around a powered wheel, but are not tied to it. How can that wheel pull the ropes without slipping?
Start
Lesson 4
A Wheel That Travels With the Car image

A Wheel That Travels With the Car

A lift hangs from ropes that pass under wheels attached to its roof. Why loop the ropes under those wheels instead of tying them straight to the lift?
Start
Lesson 5
A Floor That Sinks a Little image

A Floor That Sinks a Little

Nobody pressed a button, and the floor still moved under your feet.
Start

Locked, Braked, Caught

Lesson 6
A Call the Lift Refuses image

A Call the Lift Refuses

A lift’s doors are closed, but an unlocked door on a different floor stops it moving. How can a door far away hold the lift still?
Start
Lesson 7
Stopped Without Electricity image

Stopped Without Electricity

When every wire in the building goes dead, something still has to stop the car.
Start

Review and assessment

Lesson 8

Test: Between Floors

Review the course ideas by applying them to new situations, with kind feedback after every answer.
Locked till you take the prior lesson