The banking angle for a curved road of radius \(490\) m for a vehicle moving at \(35\) m/s is:
1.
2.
3.
4.
A body of mass \(m\) is kept on a rough horizontal surface (coefficient of friction = \(\mu).\) A horizontal force is applied to the body, but it does not move. The resultant of normal reaction and the frictional force acting on the object is given by \(\vec {F}\) where:
1. \(|{\vec {F}}| = mg+\mu mg\)
2. \(|\vec {F}| =\mu mg\)
3. \(|\vec {F}| \le mg\sqrt{1+\mu^2}\)
4. \(|\vec{F}| = mg\)
A \(5\) m long uniformly thick string rests on a horizontal frictionless surface. It is pulled by a horizontal force of \(5\) N from one end. The tension in the string at \(1\) m from the end where the force is applied is:
1. | zero | 2. | \(5\) N |
3. | \(4\) N | 4. | \(1\) N |
A body of mass \(5\) kg is suspended by the strings making angles \(60^\circ\)
Then:
(A) | \( {T}_1=25~ \text{N} \) |
(B) | \( {T}_2=25 ~\text{N} \) |
(C) | \({T}_1=25 \sqrt{3}~ \text{N} \) |
(D) | \({T}_2=25 \sqrt{3}~ \text{N} \) |
1. | (A), (B), and (C) only |
2. | (A) and (B) only |
3. | (A) and (D) only |
4. | (A), (B), (C), (D) |
A block is placed on a rough horizontal plane. A time dependent horizontal force, \(F=kt,\) acts on the block. The acceleration time graph of the block is :
1. | 2. | ||
3. | 4. |
A motorcycle is going on an overbridge of radius \(R\). The driver maintains a constant speed.
The normal force on the motorcycle as it ascends the overbridge will be:
1. increases.
2. decreases.
3. remains the same.
4. fluctuates erratically.
Two masses, \(M\) and \(m\), are attached to a vertical axis by weightless threads of combined length \(l\). They are set in rotational motion in a horizontal plane about this axis with constant angular velocity \(\omega\). If the tensions in the threads are the same during motion, the distance of \(M\) from the axis is:
1. \(\frac{M l}{M + m}\)
2. \(\frac{m l}{M + m}\)
3. \(\frac{M+m}{M}l\)
4. \(\frac{M+m}{m}l\)
A block \(A\) of mass \(7\) kg is placed on a frictionless table. A thread tied to it passes over a frictionless pulley and carries a body \(B\) of mass \(3\) kg at the other end. The acceleration of the system will be: (given \(g=10~\text{m/s}^2)\)
1. | \(100\) ms–2 | 2. | \(3\) ms–2 |
3. | \(10\) ms–2 | 4. | \(30\) ms–2 |
A plank with a box on it at one end is gradually raised at the other end. As the angle of inclination with the horizontal reaches \(30^{\circ}\), the box starts to slip and slides \(4.0\) m down the plank in \(4.0\) s. The coefficients of static and kinetic friction between the box and the plank, respectively, will be:
1. | \(0.6\) and \(0.6\) | 2. | \(0.6\) and \(0.5\) |
3. | \(0.5\) and \(0.6\) | 4. | \(0.4\) and \(0.3\) |
A block of mass \(1\) kg lying on the floor is subjected to a horizontal force given by, \(F=2\sin\omega t\) newtons. The coefficient of friction between the block and the floor is \(0.25\). The acceleration of the block will be:
1. positive and uniform
2. positive and non–uniform
3. zero
4. depending on the value of \(\omega\).