The Equations of Motion

Lab Brief #6

🎯 Your mission

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

⚡ The twist

Nature loves to surprise the careful watcher.

What you'll learn

For constant acceleration, four equations link displacement, initial and final velocity, acceleration and time. The most used are v = u + at and s = ut + ½at². Pick the equation that contains the three quantities you know and the one you want.

Key words

initial velocity (u)
The velocity an object has at the start of the timed interval.
final velocity (v)
The velocity at the end of the timed interval.

Make a hypothesis first

Before you start: write down what you think will happen, and why.

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

Get ready

🧰 What you need

ball
tape measure
phone with slow-motion video

⚠️ Safety first

Drop from shoulder height only, and keep feet clear of the landing spot.

Step 1 of 4 · Read

Think about what you just learned: say what "initial velocity (u)" and "final velocity (v)" mean in your own words before you start.

Step 2 of 4 · Do

Drop a ball from a measured height and time the fall with a phone's slow-motion camera. Use s = ut + ½at² with u = 0 to calculate g from your measurement, then compare your value with 9.81 m/s² and account for the difference.

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

Which equation would you use to find final velocity from u, a and t?

How sure are you?😐 maybe

Question 2 of 2

An object starts from rest and accelerates at 2 m/s² for 5 s. How far does it travel?

How sure are you?😐 maybe

Mind = blown

🔬 The more you look, the more nature shows you.

Nice work!

You got 0 of 2 right.

Next: Free Fall and the Value of g All lessons

🎯

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✨ More to explore

🌍 Where you see this in real life: This shows up in your everyday life more than you'd think.

🏆 Stretch challenge (try it this week): Try one experiment in real life this week — even a tiny one.

👨‍👩‍👧 For the dinner table: “What's the most surprising thing you learned today?”

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