Weight Is a Force, Mass Is Not

Lab Brief #9

🎯 Your mission

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

⚡ The twist

Energy never disappears — it just hides somewhere else.

What you'll learn

Mass is the amount of matter and is measured in kilograms. Weight is the pull of gravity on that mass and is measured in newtons. On Earth every kilogram weighs about 10 N; on the Moon it weighs less than 2 N.

Key words

gravitational field strength
The force gravity exerts on each kilogram, about 10 N/kg on Earth.
newton
The unit force is measured in.

Make a hypothesis first

Before you start: which will move faster, and why?

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

Get ready

🧰 What you need

newton meter
slotted masses
clamp stand
graph paper

⚠️ Safety first

Weight the base of the clamp stand and keep feet clear beneath hanging masses.

Step 1 of 4 · Read

Think about what you just learned: say what "gravitational field strength" and "newton" mean in your own words before you start.

Step 2 of 4 · Do

Hang five known masses from a newton meter and record the reading for each. Plot weight against mass, find the gradient, and use it to predict the weight of a 2.5 kg object.

Step 3 of 4 · Observe

Record what actually happened, including anything that did not match what you expected.

Step 4 of 4 · Record

Write a conclusion that answers the question this lesson opened with, and state your uncertainty.

Question 1 of 2

A 3 kg bag on Earth weighs about:

How sure are you?😐 maybe

Question 2 of 2

Taken to the Moon, the bag's mass would be:

How sure are you?😐 maybe

Mind = blown

⚡ Static electricity is the same physics as lightning, just smaller.

Nice work!

You got 0 of 2 right.

Next: Gravity Reaches Across Space All lessons

🎯

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✨ More to explore

🌍 Where you see this in real life: This is why airplanes can fly and why rockets reach space.

🏆 Stretch challenge (try it this week): This week, find one thing in your house that turns one kind of energy into another.

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

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