Advertisements
Advertisements
Question
Name the physical quantity whose SI unit is :
(a) m/s (b) m/s2
Advertisements
Solution
(a) Speed or velocity is expressed in m/s.
(b) Acceleration or retardation is expressed in m/s2.
APPEARS IN
RELATED QUESTIONS
When will you say a body is at non-uniform acceleration?
Give one example of a situation in which a body has a certain average speed but its average velocity is zero.
Explain the meaning of the following equation of motion :v = u + at, where symbols have their usual meanings.
A car starting from rest acquires a velocity 180m s-1 in 0.05 h. Find the acceleration.
The figure shows the displacement - time graph for four bodies A, B C and D. In each case state what information do you get about the acceleration (zero, positive or negative).

Derive the following equations for uniformly accelerated motion:
(i) v = u + at
(ii) `"S = ut" + 1/2 "at"^2`
(iii) v2 = u2 + 2aS
where the symbols have their usual meanings.
How can you find the following?
Velocity from acceleration – time graph.
A packet is dropped from a stationary helicopter, hovering at a height ‘h’ from ground level, reaches the ground in 12s. Calculate
- the value of h
- final velocity of packet on reaching the ground. (Take g = 9.8 ms−2)
Area under a v – t graph represents a physical quantity which has the unit
The velocity-time graph (Fig. 8.5) shows the motion of a cyclist. Find (i) its acceleration (ii) its velocity and (iii) the distance covered by the cyclist in 15 seconds.

