Motion and time,Fibre and fabric-vii

Fill in the blanks:

The S.I unit of speed is ___________________________ The resting position of a bob of pendulum is called _______________________position. When a body does not change its position with respect to its surrounding it is said to be at_____________________________________________ Speed of a motor vehicle is measured by an instrument called______________________ Distance travelled by a vehicle is measured by an instrument called__________________ Time taken by a pendulum to complete one oscillation is called_____________________ The metallic ball used in the pendulum is called_________________________________

What is the use of speedometer?

State the difference between uniform motion and non-uniform motion.

Ritesh was riding a bicycle on the road, he said that the wheels of the bicycle are moving along a straight line. But his friend. Saket, who was also riding a bicycle said that the wheels of the bicycle are moving circular. They then decided rather than fighting among themselves it is better to ask their science teacher.

(a) Write some types of motion.

(b) What is rectilinear motion.

(c) What is rotatory or circular motion.

What is motion?

What is the basic unit of time?

What is average speed?

Classify the following as motion along a straight line, circular or oscillatory motion :

(i) Motion of your hands while running.

(ii) Motion of a horse pulling a cart on a straight road.

(iii) Motion of a child in a merry-go-round. •

(iv) Motion of a child on a see-saw.

(v) Motion of the hammer of an electric bell.

(vi) Motion of a train on a straight bridge

.A simple pendulum takes 32s to complete 20 oscillations, what is the time period of the pendulum?

Ans.

.The distance between two stations is 240 km. A train takes 4 hours to cover this distance. Calculate the speed of the train.