Race Against Time: Exploring Speed, Motion & Pendulums through STEM

Motion and Time Experiment For Class 7

Curiosity Questions:

Have you ever wondered why a cheetah can run faster than a human or how a train’s speed is calculated?
Why do we need clocks and stopwatches to measure movement?
Can we show how something moves using a simple graph?

STEM Challenge Introduction:

In this exciting experiment, you’ll investigate how fast or slow different objects move, measure their speed, and even plot a distance-time graph to understand motion like a scientist. You’ll also observe how a simple pendulum works and use it to understand the concept of time period. This challenge is not just about movement it’s about thinking like an engineer, calculating like a mathematician, and observing like a physicist. Let’s explore how motion and time are deeply connected.

Materials Required:

Measuring Speed of Objects:

A smooth flat surface (like a floor or table).
Toy car or ball (preferably small and smooth-rolling).
Measuring tape or ruler (at least 1 meter).
Stopwatch or mobile phone with stopwatch feature.
Notebook and pencil.
Masking tape or chalk.

Simple Pendulum:

Thread (about 1 meter).
Small weight (metal nut, pebble, or key).
Ruler.
Stopwatch.
Hook or a place to hang the pendulum.

Eco-friendly Tip: Use recycled items like old toys, reused string, and keys instead of new materials.

Safety Precautions:

Ensure the floor or test surface is clear to avoid tripping.
When handling the pendulum, avoid swinging it near someone’s face.
Use scissors (for cutting thread) under adult supervision.

Step-by-Step Process:

Measure Speed of an Object

Use masking tape or chalk to mark 0 cm and 100 cm on the flat surface.
Place the toy car at the starting point (0 cm).
When ready, gently push the car and start the stopwatch.
Stop the watch the moment the car crosses the 100 cm line.
Record the time taken in seconds.
Use the formula:
Speed = Distance ÷ Time (Make sure distance is in meters and time in seconds.)
Repeat with different objects (ball, bottle cap) and compare their speeds.

Plot a Distance-Time Graph

Record the distance covered by the toy car at equal intervals (e.g., every 2 seconds).
Use graph paper to plot time on the x-axis and distance on the y-axis.
Connect the points to see if the motion is uniform (straight line) or non-uniform.

Observing a Simple Pendulum

Tie a small weight to one end of the thread and hang it from a fixed point.
Measure the length of the pendulum from the hook to the center of the weight.
Pull the pendulum slightly to one side and release it gently.
Use the stopwatch to measure the time for 10 complete swings.
Divide the total time by 10 to get the time period.

Expected Outcome:

Students will be able to calculate the speed of different moving objects.
They will create a distance-time graph that helps visualize motion.
They will observe that the time period of a pendulum remains nearly the same regardless of small swing angles.

Observation:

Which object moved the fastest? Why do you think so?
Did all objects take the same time to cover the same distance?
What did the shape of your graph tell you about how the object was moving?

STEM Concepts Behind It:

Science: Motion, speed, time period, gravity.
Technology: Use of stopwatch and measuring tools.
Engineering: Designing a setup to test motion.
Math: Calculations using formulas, graph plotting.

Concept Elaboration:

When an object moves, it covers a certain distance in a certain time. By calculating the speed, we understand how fast it is moving. The distance-time graph helps us see if the object moves at a constant speed (uniform motion) or changes its pace. The pendulum experiment demonstrates the concept of periodic motion, which is used in clocks and timing devices.

Real-Life Applications:

Speedometers in vehicles use the same formula to show how fast you’re going.
Railway and metro systems use distance-time graphs to plan efficient and safe journeys.
Pendulums were once the heart of mechanical clocks they still help us understand time.

Your STEM Challenge:

Try designing your own stopwatch-free experiment.
Can you estimate speed without using a stopwatch? Use claps, count numbers, or a metronome app to estimate time and test your accuracy by comparing with a stopwatch.

Think Further & Explore More:

How would your results change if the surface was rough or uphill?
Explore how acceleration works when objects speed up or slow down.
Research how motion sensors and automated systems use similar principles in robotics and self-driving cars.

Watch Here: Motion and Time Animation Video

Read Here : Heat Experiment For Class 7