Question 1 What is meant by the term acceleration?
Question 2 State the S.I. unit of acceleration?
Question 3 Define the term uniform acceleration. Give one example?
Question 4 Define the term non-uniform acceleration. Give one example?
Question 5 What is the acceleration of a body moving with uniform velocity?
Question 6 What type of motion is exhibited by freely falling body?
Question 7 What is retardation?
It is defined as rate of change of velocity with time.
Acceleration = Change in velocity / Time taken for change
= Final velocity – Initial velocity / Time taken for change
a = (v-u)/t
S.I. unit is m/s2 or cm/s2.
Acceleration is a vector quantity.
If a body moves with uniform velocity its acceleration will be zero because its velocity is zero.
A body has a uniform acceleration if it travels in a straight line and its velocity increases by equal amount in equal intervals of time.
For Example: Motion of freely falling body, bicycle going down the slope, ball rolling down in inclined plane.
A body has a non-uniform acceleration if its velocity increases by unequal amount in equal intervals of time.
For Example: Car running on a crowded city road(At one moment its velocity increases and at other velocity decreases.)
Acceleration can be
1) Negative(velocity decreases):Acceleration
2) Positive(velocity increases):Deceleration
A body is said to be retarded if its velocity decreases.
For Example: A train is retarded when it slow down on reaching station because its velocity decreases.
Retardation is indicated by negative sign. It means velocity of body is decreasing.
Average velocity = (v+u) / 2