If \(\mu\) between block \(A\) and inclined plane is \(0.5\) and that between block \(B\) and the inclined plane is \(0.8,\) then the normal reaction between blocks \(A\) and \(B\) will be:

1. \(180~\text N\)
2. \(216~\text N\)
3. \(0\)
4. none of these
Three blocks \(A\), \(B\) and \(C\) of mass \(3M\), \(2M\) and \(M\) respectively are suspended vertically with the help of springs \({PQ}\) and \({TU}\) and a string \({RS}\) as shown in Figure. The acceleration of blocks \(A\), \(B\) and \(C\) are \(a_{1} , a_{2}~ \text{and}~ a_{3}\) respectively.

The value of acceleration \(a_{1}\) at the moment string \({RS}\) is cut will be:
1. \(g\) downward
2. \(g\) upward
3. more than \(g\) downward
4. zero
What will be the reading of the spring balance in the given setup? (take \(g=10~\text{m/s}^2\) )

1. \(60~\text N\)
2. \(40~\text N\)
3. \(50~\text N\)
4. \(80~\text N\)
| 1. |
\(\overrightarrow N+\overrightarrow T+\overrightarrow W=0\) |
2. | \(T^2=N^2+W^2\) |
| 3. | \(T = N + W\) | 4. | \(N = W \tan \theta\) |
A particle of mass \(m\) having speed \(v\) goes in a vertical circular motion such that its centre is at its origin, as shown in the figure. If at any instant the angle made by the string with a negative \(y\text-\)axis is \(\theta\) then the tension in the string is:
[Take radius = \(R\)]

1. \(mg\sin\theta+ \frac{mv^2}{R}\)
2. \(mg\cos\theta- \frac{mv^2}{R}\)
3. \(mg\cos\theta+ \frac{mv^2}{R}\)
4. \(mg\sin\theta- \frac{mv^2}{R}\)
The angle of banking for a cyclist taking a turn at a curve is given by \(\tan\theta = \frac{v^{n}}{rg}\) where symbols have their usual meaning. The value of \(n\) is:
| 1. | \(1\)
|
2. | \(2\)
|
| 3. | \(3\)
|
4. | \(4\) |
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. \(mg-\frac{mv^{2}}{R}\)
2. \(mg+\frac{mv^{2}}{R}\)
3. \(mg\)
4. \(\frac{mv^{2}}{R}\)
A simple pendulum hangs from the roof of a train moving on horizontal rails. If the string is inclined towards the front of the train, then the train is:
| 1. | moving with constant velocity. |
| 2. | in accelerated motion. |
| 3. | in retarded motion. |
| 4. | at rest. |
The kinetic energy \(K\) of a particle moving in a circular path varies with the distance covered \(S\) as \(K = aS^2\) where \(a\) is constant. The angle between the tangential force and the net force acting on the particle is: (\(R\) is the radius of the circular path)
1. \(\tan^{-1}\left(\frac{S}{R}\right)\)
2. \(\tan^{-1}\left(\frac{R}{S}\right)\)
3. \(\tan^{-1}\left(\frac{a}{R}\right)\)
4. \(\tan^{-1}\left(\frac{R}{a}\right)\)
Choose the incorrect alternative:
| 1. | Newton's first law is the law of inertia. |
| 2. | Newton's first law states that if the net force on a system is zero, the acceleration of any particle of the system is not zero. |
| 3. | Action and reaction act simultaneously. |
| 4. | The area under the force-time graph is equal to the change in momentum. |