How Machines Help Us

What You'll Learn

A force is a push or pull that can change an object's motion, shape, or direction. Forces are measured in Newtons and can act through contact or at a distance.

Key Words

resistance
gravity

Materials Needed

weights
tape
ruler

Safety First

Work in a well-ventilated area when using vinegar or other strong-smelling substances.
Dispose of materials properly after the experiment.
Handle glass items carefully to avoid breakage.

Steps

Step 1 — Read

Read about Energy and write down three key facts.

Step 2 — Do

Set up a pendulum with string and a washer. Change the string length and count swings per minute for each. Graph your results.

Step 3 — Observe

Note any unexpected results and think about why they happened.

Step 4 — Record

Share your findings with the class or a partner and discuss what you learned.

Check Your Understanding

Question 1

1 of 3

Which is an example of potential energy?