For \(L = 3.0~\text{m,}\) the total torque about pivot \(A\) provided by the forces as shown in the figure is:
1. | \(210 ~\text{Nm}\) | 2. | \(140 ~\text{Nm}\) |
3. | \(95 ~\text{Nm}\) | 4. | \(75 ~\text{Nm}\) |
A constant torque of 1000 N-m turns a wheel of moment of inertial 200 about an axis through its centre. Its angular velocity after 3 s is
1. 1 rad/s
2. 5 rad/s
3. 10 rad/s
4. 15 rad/s
An automobile engine develops 100 kW when rotating at a speed of 1800 rev/min. What torque does it deliver ?
1. 350 N-m
2. 440 N-m
3. 531 N-m
4. 628 N-m
A force\(- F \hat k\) acts on \(O\), the origin of the coordinate system. The torque at the point \((1,-1)\) will be:
1. \(-F(\hat i + \hat j)\)
2. \(F(\hat i + \hat j)\)
3. \(-F(\hat i -\hat j)\)
4. \(F(\hat i - \hat j)\)
In the following figure, a weight W is attached to a string wrapped round a solid cylinder of mass M mounted on a frictionless horizontal axle at O.
If the weight starts from rest and falls a distance h, then its speed at that instant is
1. Proportional to \(\text R\)
2. Proportional to \(1 \over R\)
3. Proportional to \(1 \over R^2\)
4. Independent of \(\text R\)
Assertion : A ladder is more apt to slip when you are high up on it than when you just begin to climb
Reason : At the high point on a ladder, the torque is large and on climbing up the torque is small
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 \(A\), \(8~\)N at \(B\), \(6\) N at \(C\), and \(9~\)N 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 wheel has angular acceleration of 3.0 rad/ and an initial angular speed of 2.00 rad/sec. In a time of 2 sec it has rotated through an angle (in radian) of
1. 10
2. 12
3. 4
4. 6
If a force acts on a body at a point away from the centre-of-mass, then:
1. | Linear acceleration changes |
2. | Angular acceleration changes |
3. | Both change |
4. | None of these |
In figure (a), a meter stick, half of which is wood and the other half steel is pivoted at the wooden end at O and a force F is applied to the steel end a. In figure (b) the stick is pivoted at the steel eid at O' and the same force F is applied at the wooden end at a' The angular acceleration
1. in (a) is greater than in (b)
2. in (b) is greater than in (a)
3. equal both in (a) and (b)
4. none of the above.