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 bullet is fired from a gun with a speed of 100 m/s in order to hit a target 100m away. At what height above the target should the gun be aimed? (The resistance of air is negligible and g = 10 m/s2)
5 cm
10 cm
15 cm
20 cm
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)
Two particles A and B are connected by a rigid rod AB. The rod slides along perpendicular rails as shown here. The velocity of A to the right is 10 m/s. What is the velocity of B when angle α = 60°?
9.8 m/s
10 m/s
5.8 m/s
17.3 m/s
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
If , then the value of is
(A2 + A2 + AB)1/2
A + B
(A2 + B2 + √3 AB)1/2
The angle between the two vectors will be
0°
45°
90°
180°
A stone tied to the end of a string of 1 m long is whirled in a horizontal circle with a constant speed. If the stone makes 22 revolutions in 44s, what is the magnitude and direction of acceleration of the stone?
and direction along the radius towards the centre
π2 ms-2 and direction along the radius away from centre
π2 ms-2 and direction along the radius towards the centre
π2 ms-2 and direction along the tangent to the circle
