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
Which of the following is not a vector quantity?
Speed
Velocity
Torque
Displacement
The resultant of × 0 will be equal to
zero
A
zero vector
unit vector
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
When milk is churned, cream gets separated due to
centripetal force
centrifugal force
frictional force
gravitational force
The vector sum of two forces is perpendicular to their vector differences. In that case, the forces
are not equal to each other in magnitude
cannot be predicted
are equal to each other
are equal to each other in magnitude
The magnitudes of vectors are 3,4 and 5 units respectively. If , the angle between is
cos-1 (0.6)
The angle between the two vectors will be
0°
45°
90°
180°
The maximum range of a gun of horizontal terrain is 16 km. If g = 10 ms-2 , then muzzle velocity of a shell must be
160 ms-1
200√2 ms-1
400 ms-1
800 ms-1
Two bodies of same mass are projected with the same velocity at an angle 30° and 60° respectively. The ratio of their horizontal ranges will be
1 : 1
1 : 2
1 : 3
1 : √2
