A block of mass M is pulled by a force F, making an angle with the horizontal on a smooth horizontal surface as shown. If a is the acceleration of block on the surface, then the contact force between the block and the surface will be:
1. Mg + Macos
2. Mg - Macos
3. Mg + Matan
4. Mg - Matan
A body of mass m is moving on a concave bridge ABC of the radius of curvature R at a speed v. The normal reaction of the bridge on the body at the instant it is at the lowest point of the bridge is:
1.
2.
3. mg
4.
A block B of mass \(3\) kg is kept on block A of mass \(5\) kg in a lift accelerating upward with an acceleration of \(g.\) The reaction by A on B is:
1. | \(10g\) | 2. | \(16g\) |
3. | \(4g\) | 4. | \(6g\) |
If the force acting on a system is zero, the quantity which remains constant is:
1. | Force | 2. | Linear momentum |
3. | Speed | 4. | Kinetic energy |
Two blocks, A and B, of masses 2m and 4m are connected by a string. The block of mass 4m is connected by a spring (massless). The string is suddenly cut. The ratio of the magnitudes of accelerations of masses 2m and 4m at that instant will be:
1. | 1: 2 | 2. | 2: 1 |
3. | 1: 4 | 4. | 4: 1 |
The reading of spring balance in the depicted figure will be:
1. | 0 N | 2. | 20 N |
3. | 10 N | 4. | 5 N |
The angle of banking for a cyclist taking a turn at a curve is given by tan where symbols have their usual meaning. The value of n is:
1. | 1
|
2. | 2
|
3. | 3
|
4. | 4 |
The maximum constant speed with which a car can move on a flat horizontal circular road with the radius of curvature 20 m and a coefficient of static friction 0.5 is: (g = 10 )
1. | 36 km/h | 2. | 54 km/h |
3. | 72 km/h | 4. | 90 km/h |
A 100 kg gun fires a ball of 1 kg horizontally from a cliff at a height of 500 m. It falls on the ground at a distance of 400 m from the bottom of the cliff. The recoil velocity of the gun is: (Take g = 10 m/s2)
1. 0.2 m/s
2. 0.4 m/s
3. 0.6 m/s
4. 0.8 m/s
A metal sphere is suspended from a wall by a string. The forces acting on the sphere are shown in the figure. Which of the following statements is NOT correct?
1. |
\(\vec N+\vec T+\vec W=0\) |
2. | \(T^2=N^2+W^2\) |
3. | \(T = N + W\) | 4. | \(N = W \tan \theta\) |