 # Motion and Measurement of Distances

### Question:

What type of motion do the following objects have?
(a) the galloping of a horse
(b) the needle of a sewing machine
(c) the movements of a mosquito
(d) the blades of an electric fan
(e) the smoke from a lighted dhoopbatti
(f) wheels of moving car.

(a) The galloping of a horse: Linear motion.
(b) The needle of a sewing machine: Periodic motion.
(c) Movement of a mosquito: Random motion.
(d) Blade of an electric fan: Circular motion.
(e) The smoke from a lighted dhoopbatti: Random motion.
(f) Wheels of moving car: Linear motion and Rotational motion.

### Motion and Measurement of Distances

#### Q 1.

Give two examples each of modes of transport used on land, water and air.

#### Q 2.

Define rest and motion.

#### Q 3.

While measuring the length of a knitting needle, the reading of the scale at one    end is 3.0 cm and at the other end is 33.1 cm. What is the length of the needle?

#### Q 4.

How can a measured length be expressed?

#### Q 5.

Why can a pace or a footstep not be used as a standard unit of length?

#### Q 6.

The distance between Radha's home and her school is 3250 ,m. Express this distance in km.

#### Q 7.

Why do we need standard unit for measurement?

#### Q 8.

The height of a person is 1.65 m. Express it in cm and mm.

#### Q 9.

Are senses reliable for accurate measurement?

#### Q 10.

Give one example of linear motion.

#### Q 11.

Give one example each of the following types of motion:

(a) Linear
(b) Translation
(c) Circular
(d) Periodic.

#### Q 12.

Why could you not use an elastic measuring tape to measure distance? What would be some of the problems you would meet in telling someone about a distance you measured with an elastic tape?

#### Q 13.

Fill in the blanks:
(i) One metre is___________
(ii) Five kilometre is___________
(iii) Motion of a child on a swing is_____________ .
(iv) Motion of the needle of a sewing machine is_______________ .
(v) Motion of wheel of a bicycle is_____________ .

#### Q 14.

Give an example of circular motion.

#### Q 15.

Name the measuring device which can be used for measuring the girth of a tree.

#### Q 16.

Find the length and breadth of given rectangle in mm and cm. #### Q 17.

Name the device used to measure the following:
(e) Cloth for curtain.
(f) Circumference of round table.

#### Q 18.

How many centimetres are there in 1 m?

#### Q 19.

Why can hand span and arm length not be used as standard units of length?

#### Q 20.

Give two examples for each of the following motions:
(i) Linear motion
(ii) Spinning motion
(iii) Oscillatory motion
(iv) Periodic motion
(v) Vibrational motion
(vi) Circular motion
(vii) Random motion

#### Q 21.

Give two examples of periodic motion.

#### Q 22.

Arrange the following lengths in their increasing magnitude :
1 metre, 1 centimetre, 1 kilometre, 1 millimetre.

#### Q 23.

Name the types of motion in which a body moves along a straight path

#### Q 24.

State two precautions to be observed while measuring length with the help of a metre scale.

#### Q 25.

Define the term standard unit.

#### Q 26.

Write the similarities and differences between the motion of a bicycle and a ceiling fan that has been switched on.

#### Q 27.

What type of motion do the following objects have?
(a) the galloping of a horse
(b) the needle of a sewing machine
(c) the movements of a mosquito
(d) the blades of an electric fan
(e) the smoke from a lighted dhoopbatti
(f) wheels of moving car.

#### Q 28.

Give the unit for measuring the following:
(a) Distance between Delhi and Jaipur.
(b) Thickness of a coin.