The ratio of SI units to CGS units of retardation is
10-2
102
10
10-1
The moon is m from the earth. A radar signal transmitted from the earth will reach the moon in about
5.2 s
1.3 s
2.6 s
0.70 s
A body covers half the distance with a speed of 20 m/s and the other half with a speed of 30 m/s. The average velocity of the body during the whole journey is
zero
24 m/s
25 m/s
none of these
A train passes over a 400 m long bridge. If the speed of the train is 30 m/s and the train takes 20 s to cross the bridge, find the length of the train.
400 m
600 m
800 m
200 m
Which of the following distance-time graph (fig.1.45) represents the acceleration motion of a body ?
The SI unit for angular velocity is
m/s
rad
rad/s
m/rad
Choose the wrong statement :
Retardation is a vector quantity
Acceleration due to gravity is a vector quantity
Average speed is a vector quantity
Displacement is a vector quantity
The velocity of a body at rest is always
unity
negative
infinite
The velocity-time graph of a body moving in a fixed direction is a straight line.Then the body has
constant speed
constant velocity
constant acceleration
variable acceleration
In Fig.1.34, BC represents a body moving
backward with uniform velocity
forward with uniform velocity
backward with non-uniform velocity
forward with non-uniform velocity
