A body constrained to move in Y-direction is subjected to a force given by . What is the work done by this force in moving the body through a distance of 10 m along Y-axis?
190 J
160 J
150 J
20 J
A boat is sent across a river with a velocity of 8 km h-1. If the resultant velocity of boat is 10 km h-1 , then velocity of river is
12.8 km h-1
6 km h-1
8 km h-1
10 km h-1
A person swims in a river aiming to reach exactly opposite point on the bank of a river. His speed of swimming is 0.5 m/s at an angle 120° with the direction of flow of water. The speed of water in stream is
1.0 m/s
0.5 m/s
0.25 m/s
0.43 m/s
An electric fan has blades of length 30 cm measured from the axis of rotation. If the fan is rotating at 120 rev/min, the acceleration of a point on the tip of the blade is
1600 ms-2
47.4 ms-2
23.7 ms-2
50.55 ms-2
A bus is moving on a straight road towards north with a uniform speed of 50 km/h. If the speed remains unchanged after turning through 90°, the increase in the velocity of bus in the turning process is
7.07 km/h along south-west direction
zero
50 km/h along west
70.7 km/h along north-west direction
Which of the following is not a vector quantity?
Speed
Velocity
Torque
Displacement
When milk is churned, cream gets separated due to
centripetal force
centrifugal force
frictional force
gravitational force
The vectors and are such that | + | = | - | then angle between the two vectors will be
45°
60°
75°
90°
The angle between the two vectors will be
0°
180°
The position vector of a particle, is . The velocity of the particle is
directed towards the origin
directed away from the origin
parallel to the position vector
perpendicular to the position vector
