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
A stone is attached to one end of a string and rotated in a vertical circle. If string breaks at the position of maximum tension, it will break at
A
B
C
D
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 particle of mass m is projected with velocity v making an angle of 45° with the horizontal. When the particle lands on the level ground the magnitude of the change in its momentum will be
2 mv
mv √2
zero
The angle between the two vectors will be
0°
45°
90°
180°
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
50 km/h along west
70.7 km/h along north-west direction
A particle starting from the origin (0, 0) moves in a straight line in the (x, y) plane. Its coordinates at a later time are (√3, 3). The path of the particle makes with the x-axis an angle of
30°
60°
A body is whirled in a horizontal circle of radius 20 cm. It has an angular velocity of 10 rad/s. What is its linear velocity at any point on circular path?
√2 m/s
2 m/s
20 m/s
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
The resultant of × 0 will be equal to
zero vector
unit vector