To maintain a rotor at a uniform angular speed of \(200\) rad s-1, an engine needs to transmit a torque of \(180\) N-m. What is the power required by the engine?
1. \(33\) kW
2. \(36\) kW
3. \(28\) kW
4. \(76\) kW
The value of M, as shown, for which the rod will be in equilibrium is:
1. | 1 kg | 2. | 2 kg |
3. | 4 kg | 4. | 6 kg |
A rope of negligible mass is wound around a hollow cylinder of mass \(3\) kg and radius \(40\) cm. What is the angular acceleration of the cylinder if the rope is pulled with a force of \(30\) N?
(Assume that there is no slipping.)
1. \(21\) rad/s2
2. \(24\) rad/s2
3. \(20\) rad/s2
4. \(25\) rad/s2
In the figure given below, O is the centre of an equilateral triangle ABC and are three forces acting along the sides AB, BC and AC. What should be the magnitude of so that total torque about O is zero?
1.
2.
3.
4. Not possible
A wheel with a radius of 20 cm has forces applied to it as shown in the figure. The torque produced by the forces of 4 N at A, 8N at B, 6 N at C, and 9N at D, at the angles indicated, is:
1. 5.4 N-m anticlockwise
2. 1.80 N-m clockwise
3. 2.0 N-m clockwise
4. 3.6 N-m clockwise
A uniform cube of mass \(m\) and side \(a\) is placed on a frictionless horizontal surface. A vertical force \(F\) is applied to the edge as shown in the figure. Match the following (most appropriate choice).
List- I | List- II | ||
(a) | \(mg/4<F<mg/2\) | (i) | cube will move up. |
(b) | \(F>mg/2\) | (ii) | cube will not exhibit motion. |
(c) | \(F>mg\) | (iii) | cube will begin to rotate and slip at A. |
(d) | \(F=mg/4\) | (iv) | \(a/3\) from A, no motion. | normal reaction effectively at
1. | a - (i), b - (iv), c - (ii), d - (iii) |
2. | a - (ii), b - (iii), c - (i), d - (iv) |
3. | a - (iii), b - (i), c - (ii), d - (iv) |
4. | a - (i), b - (ii), c - (iv), d - (iii) |
Which of the following is the value of the torque of force \(F\) about origin \(O:\)
1. \(\vec{\tau}=5(1-\sqrt{3}) \hat{k}\) N-m
2. \(\vec{\tau}=5(1-\sqrt{3}) \hat{j}\) N-m
3. \(\vec{\tau}=5(\sqrt{3}-1) \hat{i}\) N-m
4. \(\vec{\tau}=\sqrt{3} \hat{j}\) N-m
A force \(\vec{F}=\hat{i}+2\hat{j}+3\hat{k}~\text{N}\) acts at a point \(\hat{4i}+3\hat{j}-\hat{k}~\text{m}\). Let the magnitude of the torque about the point \(\hat{i}+2\hat{j}+\hat{k}~\text{m}\) be \(\sqrt{x}~\text{N-m}\). The value of \(x\) is:
1. | \(145\) | 2. | \(195\) |
3. | \(245\) | 4. | \(295\) |
A uniform beam, \(3.0\) m long, of weight \(100\) N has a \(300\) N weight placed \(0.5\) m from one end. The beam is suspended by a string \(1.0\) m from the same end. A diagram of the weights placed on the beam is given below:
How far from the other end must a weight of \(80\) N be placed for the beam to be balanced?
1. | \(0.75\) m | 2. | \(2.25\) m |
3. | \(1.25\) m | 4. | \(1.875\) m |