A bus decelerating with 4m/s2 changes its speed from 60 m s-1 to a certain value in 5 s. The final speed is:
Acceleration = – 4m/s2; Initial speed, u = 60 m s-1
Time taken = 5s
Acceleration = change in velocity per unit time
v= u + at
v = 60 – 4 x 5 = 40 m/s
If the upward direction is taken as positive what is the sign of velocity and acceleration when a body falls freely from a height.
A body moving along a straight line at 20m/s undergoes an acceleration of -4m/s2. After two seconds its speed will be
A boy throws a ball up and catches it when the ball falls back. In which part of the motion the ball is accelerating?
Choose the correct option:
Distance is a scalar quantity that refers to "how much ground an object has covered" during it's motion.
Acceleration is a vector quantity that is defined as the rate at which an object changes it's velocity.
Velocity is a vector quantity which refers to the speed of an object in a particular direction.
The ratio of C.G.S. to M.K.S. unit of acceleration is:
M.K.S. unit of acceleration = 1m/s2
C.G.S unit of acceleration/ M,K.S unit of acceleration =
1cm/s2 / 1m/s2
= 1cm / 100 cm
The S.I. unit of acceleration is:
Calculating acceleration involves dividing velocity by time Or we can say, dividing the meter per second by the second. i.e.
[ m/s2 = m/s / s ]
Therefore, option ( c) ms-2 is the correct answer.
If a moving body comes to rest, then its acceleration is-
If a moving body comes to rest, then its acceleration is negative, as it's velocity becomes zero.
If the velocity of a body changes uniformly from u to v in time t, the sum of average velocity and acceleration is:
The correct option is Option D
Average velocity = (u+v)/t
Acceleration = (v-u)/t
Thus sum of average velocity and acceleration
= (u + v )/t + (v-u)/t
Acceleration is defined as the rate of change of: