Moving Things and Types of Motion
Class 6 Science · Chapter 5: Measurement of Length and Motion · NCERT Curiosity section 5.6–5.7
Learn
At a village fair, Anjali watches a toy train on a straight track, a giant wheel turning, and a big swing going to and fro. Each moves in a different way!
Linear motion: moving along a straight line: a train on a straight track, an apple falling, a ball rolling on a flat floor. Circular motion: moving in a circle around a centre: a merry-go-round, the tip of a fan blade, a stone whirled on a string.
Oscillatory motion: moving to and fro about a fixed point: a swing, a pendulum, a plucked guitar string, a see-saw. Motions that repeat after equal intervals of time, like a pendulum or a fan, are called periodic.
Some things show more than one type of motion at once: a bicycle moves forward in a straight line (linear) while its wheels spin (circular).
Explore: sort the motions.
- Linear, circular or oscillatory?
Remember
- Linear: straight line. Circular: round a centre. Oscillatory: to and fro.
- Motion that repeats after equal times is periodic; some objects show more than one motion.
Quick check
What type of motion does a swinging pendulum have?
- Oscillatory
- Linear
- Circular
- No motion
Answer
Oscillatory. A pendulum moves to and fro about a fixed point: oscillatory (and periodic).
Think about it
Name the types of motion you can spot in a moving bicycle and its rider's legs.
One answer
The bicycle as a whole moves in a line (linear), its wheels and pedals turn (circular), and the rider's knees move up and down again and again (to and fro, like oscillation).
Practice
Practise with fresh questions at three levels (easy, medium, hard), some answered hands-on, with hints and worked answers. Get 4 of your last 5 right to finish the topic.