Page 28 - Science Class 6 Times Publication

Worked out example
A man travels 240 m distance in 1 minute. Calculate his speed.
Solution:

Distance (d) = 240m

Time (t) =1 minute = 60s

Speed (v) = ?

We have, Distance covered (d)
Speed =
Time taken (t)
= 24060
= 4 m/s

Therefore, the speed of the man is 4m/s.

Main Points to Remember

1. A body is said to be at rest if it does not change its position
with respect to its surrounding.
2. A body is said to be in motion if it changes its position with
respect to its surrounding.

3. Linear motion, circular motion, rotatory motion, oscillatory
motion and random motion are various types of motion.
4. Force is an external agency that changes or tries to change
the state of motion or rest of an object.

5. Force can change:
i) state of rest or motion

ii) shape and size of an object
iii) direction of an object

iv) speed of motion
6. Speed is de ned as the distance covered by an object in unit
time.

7. Velocity is dened as the displacement travelled in unit time.

Times' Crucial Science and Environment 24 Book 6