Write true or false of the following statement.
A ball is thrown vertically upwards. Its motion is uniform throughout.
Match the following:
|Column A||Column B|
|(a) Circular motion||(1) a running fan|
|(b) periodic motion||(2) a car moving in a market|
|(c) Vibratory motion||(3) revolution of earth around the sun|
|(d) Rotatory motion||(4) motion of wire of a guitar|
|(e) Non uniform motion||(5) motion of pendulum of a clock|
Select the correct alternative
A boy goes from his house to school by bus at a speed of 20 km h_1 and returns back through the same route at a speed of 30 km h_1. The average speed of his journey is.