Motion .

Question 1

Define position and reference point ?

Answer 1

Position - location of object .

Reference point - point from which location of object is measured.

Question 2

What are instantaneous speed ?

Answer 2

It is the speed of an object at a particular moment ( instant ) in time…

Question 3

What are instantaneous velocity ?

Answer 3

It is the velocity of an object at any moment (instant ) in time.

Question 4

What is retardation?

Answer 4

If velocity of object decreases with time and its direction is opposite to the direction of velocity, then that motion is negative acceleration.

Examples : when we apply breaks velocity decrease and vehicle will decelerate .

Question 5

A boy throws a ball up and catches it when the ball falls back . In which part of the motion is the ball declarating ?

Answer 5

As the ball goes up , it’s speed decreases and as it comes down , it’s speed increases. Thus, it declarates while going up .

Question 6

What does speedometer measure ?

Answer 6

It is used to measure the instantaneous speed of car .

Question 7

If a body is moving at constant speed in circular path it’s velocity and acceleration is ?

Answer 7

Velocity is constant . Acceleration is zero .

Question 8

Object moving with uniform velocity has_____ acceleraeion r?

Answer 8

Zero .