Write what you think. We will return to this idea at the end.
Read at the pointerBLUE METER
Read both scales
Follow the pointer across. Read the mass on the g scale and the weight on the N scale.
Read it yourself
What does the meter show?
Read both scales at the red pointer. Say your answers, or type them below.
Mass · grams150 gRead the g scale
Weight · newtons1.5 NRead the N scale
Count the spaces between labelled marks carefully.
Choose an example object
Example masses only. Measure your own classroom objects.
Each space between marks = 25 g or 0.25 N.
Mass → gThe amount of matter in an object.
Weight → NThe force of gravity pulling on it.
Same headings as your book
Our example results
Object
Mass (g)
Weight (N)
Read a meter, then add an example here.
These are demonstration readings, not measurements of your actual objects. This table clears when the page reloads.
Measure your classroom objects and record both units.
The invisible pull
What is gravity?
Gravity is a force that pulls objects with mass towards each other.
Earth’s gravity pulls objects towards the centre of Earth.
When you let go of a pencil, gravity pulls it towards the ground.
A pulling force
What is weight?
Weight is the force of gravity acting on an object.
We measure weight in newtons using a force meter.
Weight → newtons (N)
The object pulls on the spring. The spring stretches, and we read the N scale.
The matter in an object
What is mass?
Mass is the amount of matter in an object.
Matter is the stuff that objects are made from.
Mass → grams (g) or kilograms (kg)
Two identical blocks together have twice the mass of one block.
Spot the pattern · In the same place
How are mass and weight related?
In the same place, an object with a greater mass has a greater weight.
If you double the mass, you double the weight, because the strength of gravity is the same.
Greater mass → greater weight
On Earth: 100 g has a weight of about 1 N. These examples use our classroom approximation.
Explanation 1 of 4
Teacher reference
The relationship holds when gravitational field strength stays the same. Mass and weight are different quantities. The values above are illustrative, using 10 N/kg. Gravity and weight explanations checked against NASA Space Place: What is gravity? and NASA: weight equation.
Final reflection · Write in your book
What do you understand now?
Answer in full sentences. Use your measurements as evidence.
QUESTION 1
What is gravity?
Example answerGravity is a force that pulls objects with mass towards each other. Earth’s gravity pulls objects towards its centre.
QUESTION 2
What is weight?
Example answerWeight is the force of gravity acting on an object. We measure it in newtons (N).
QUESTION 3
What is mass?
Example answerMass is the amount of matter in an object. We measure it in grams (g) or kilograms (kg).
QUESTION 4
Explain the correlation between weight and mass.
Example answerIn the same place, greater mass means greater weight. Doubling the mass doubles the weight. For example, on Earth, 100 g weighs about 1 N and 200 g weighs about 2 N.
Return to “I think gravity is...” and explain how your thinking has changed.