The postion vector of a particle is
The velocity vector of the particle is
1. parallel to position vector
2. perpendicular to position vector
3. directed towards the origin
4. directed away from the origin
A force N displaces the body by m in 2 s. Power generated will be
1. 11 W
2. 6 W
3. 22 W
4. 12 W
A particle moves in the x-y plane under the influence of a force such that its linear momentum is
where A and k are constants. The angle between the force and momentum is
1. 0
2. 30
3. 45
4. 90
At what angle must the two forces (x+y) and (x-y) act so that the resultant may be ?
1.
2.
3.
4.
A particle is moving eastwards with a velocity of 5 ms-1. In 10 s the velocity changes to 5 ms-1 northwards. The average acceleration in this time is
1. towards north-east
2.
3. zero
4. towards north-west
Consider a collection of large number of particles each with speed v. The direction of velocity is randomly distributed in the collection. The magnitude of the relative velocity between a pair of particles averaged over all the pairs in the collection is
1.
2. greater than
3. less than
4. zero
A man stqanding on a road has to hold his umbrella at 30o with the vertical to keep the rain away. He throws the umbrella and starts running at 10 . He finds that raindrops are hitting his head vertically. The actual speed of raindrops is
1. 20
2.
3.
4. 10
A particels of mass m is moving in a horizontal circle of radius r, under a centripetal force , where k is a constant
1. The potential energy of the particle is zero
2. The potential energy of the particle is
3. The total energy of the particle is
4. The kinetic energy of the particle is
A particle is moving with a constant speed v in a circle. What is the magnitude of average after half rotation
1. 2v
2.
3.
4.
A point P moves in counter-clockwise direction on a circular path as shown in the figure. The movement of P is such that it sweeps out a length 5 , where s is in metre and t is in second. The radius of the path is 20 m. The acceleration of P when t = 2s is nearly
1. 13
2. 12
3. 7.2
4. 14
A can filled with water is revolved in a vertical circle of radius 4 m and the water does not fall down. The time period for a revolution is about
1. 2 s
2. 4 s
3. 8 s
4. 10 s
A particle is moving in a circle of radius R in such a way that at any instant the normal and tangential components of its acceleration are equal. If its speed at t = 0 is v0, the time taken to complete the first revolution
1.
2.
3.
4.
A particle of mass m is rotating in a horizontal circle of radius R and is attached to a hanging mass M as shown in the figure. The speed of rotation required by the mass m keep M steady is
1.
2.
3.
4.
A particle originally at a rest at the highest point of a smooth circle in a vertical plane, is gently pushed and starts sliding along the circle. It will leave the circle at a vertical distance h below the highest point such that
1. h = 2R
2.
3. h = R
4.
A particle is moving with velocity , where k is a constant. The general equation for its path is
1.
2.
3. xy = constant
4.
An aircraft is flying at a height of 3400 m above the ground. If the angle subtended at a ground observation point by the aircraft positions 10 s apart is 30, then the speed of aircraft is
1. 19.63
2. 1963
3. 108
4. 196.3
A particle of mass m is projected with a velocity v making an angle of 30 with the horizontal. The magnitude of angular momentum of a projectile about the point of projection when the particle is at its maximum height H is
1.
2. zero
3.
4.
Two bodies are projected from the same point with equal speeds in search directions that they both strike the same points on a plane whose inclination is . If be the angle of projection of the first body with the horizontal the ratio of their times of light is
1.
2.
3.
4.
Three balls are dropped from the top fo a building with equal speed at different angles. When the balls strike ground their velocities are respectively, then
1.
2.
3.
4.
A particle moves along a parabolic path in such a way that the x- components of velocity remains constant and has a value . The acceleration of the projectile is
1.
2.
3.
4.
If and the magnitudes of are 5,4 and 3 units, then angle between is
1.
2.
3.
4.
A particle moves in the xy plane with only an x-component of acceleration of 2 . The particle starts from the origin at t = 0 with an initial velocity having an x-component of 8 and y-component of -15 . The total velocity vector at any time t is
1.
2. zero
3.
4. directed along z-axis
A unit vector along incident ray of lights is . The unit vector for the corresponding refracted ray of lights is . is a unit vector normal to the boundary of the medium and directed towards the incident medium. If m be the refractive index of the medium, then Snell's law (2nd) of refraction is
1.
2.
3.
4.
In the figure, the time taken by the projectile to reach from A to B is t. Then the distance AB is equal to
A body is projected with velocity from the point A as shown in fig. .At the same time another body is projected vertically upwards from B with velocity . The point B lies vertically below the highest point. For both the bodies to collide, should be
1. 2
2.
3. 0.5
4. 1
A particle is projected with a certain velocity at an angle above the horizontal from the foot of an inclined plane of inclination . If the particle strikes the plane normally then is equal to
1.
2. 45
3. 60
4.
The trajectory of a particle in a vertical plane is , where a and b are constants and x and y are respective horizontal and vertical distances of the projectile from the point of projection. The maximum height attained by the particle and the angle of projection from the horizontal
1.
2.
3.
4.
A particle is projected from the ground with an initial speed of v at an angle with horizontal. The average velocity of the particle between its point of projection and highest point of trajectory is
1.
2.
3.
4.
Two balls A and B are thrown with speeds u and u/2, respectively. Both the balls cover the same horizontal distance before returning to the plane of projection. If the angle of projection of ball B is 15o with the horizontal, then the angle of projection of A is
1.
2.
3.
4.