Pulleys Lift Loads

Lab Brief #4

🎯 Your mission

Predict it first. Then prove yourself right (or wrong).

⚡ The twist

The opposite of what you expect is often what happens.

What you'll learn

A pulley is a grooved wheel that holds a rope and lets you change the direction of a force. Pulling down on one side lifts a load on the other, and combining several pulleys makes heavy objects far easier to raise.

Key words

direction
The way something moves or points, like up, down, or left.
force
A push or pull that can make an object move or stop.
pulley
A wheel with a rope that helps you lift heavy things.

Make a hypothesis first

Predict: what happens if you double the force?

Say your guess out loud — then find out if you were right.

Get ready

🧰 What you need

weights
spring scale

⚠️ Safety first

Have an adult check your set-up before you start, and tidy everything away afterwards.

Step 1 of 4 · Read

Look at the vocabulary words and write a definition for each in your own words.

Step 2 of 4 · Do

Test friction: pull a weighted box across 4 surfaces (carpet, tile, sandpaper, foil). Use a spring scale to measure the force needed for each.

Step 3 of 4 · Observe

Draw a detailed diagram of what you observe.

Step 4 of 4 · Record

Write a conclusion: what did your results show? Did they match your prediction?

Question 1 of 3

What is a fulcrum?

How sure are you?😐 maybe

Question 2 of 3

What causes an object to accelerate?

How sure are you?😐 maybe

Question 3 of 3

Which is NOT a simple machine?

How sure are you?😐 maybe

Mind = blown

🔥 A bolt of lightning is 5 times hotter than the surface of the sun.

Nice work!

You got 0 of 3 right.

Next: How Sound Waves Travel All lessons

🎯

Next Smart Experiment

We'll pick an experiment that matches exactly how you're thinking right now.

✨ More to explore

🌍 Where you see this in real life: You use this every time you flip a light switch, ride a bike, or kick a ball.

🏆 Stretch challenge (try it this week): Time how long a small ball rolls down something, then change the slope and try again.

👨‍👩‍👧 For the dinner table: “Show me something at home that uses this kind of energy.”

⚡Share card

Share this experiment

Send it to a parent who's looking for a 10-minute kitchen science win.

Pulleys Lift Loads

Next Smart Experiment

Share this experiment

Pulleys Lift Loads

Done with science? Try something else

Your Cart (0)