The moment of inertia of a rod of mass M, length l about an axis perpendicular to it through one end is:
1.
2.
3.
4. Can't be determined
The moment of inertia of a ring about a tangent to the circle of the ring is:
1.
2.
3.
4.
Angular velocity at any time \(t\) of a rotating body is given as \(\omega \left(t\right) = \left(\omega\right)_{0} + at\). Its Magnitude of angular acceleration:
1. is always constant.
2. increases with time.
3. decreases with time.
4. first increases then decreases with time.
The moment of inertia of a disc about one of its diameters is:
1. | \(MR^2\) | 2. | \(\dfrac{MR^2}{3}\) |
3. | \(\dfrac{2MR^2}{3}\) | 4. | \(\dfrac{MR^2}{4}\) |
A 3 m long ladder weighing 20 kg leans on a frictionless wall. Its feet rest on the floor 1 m from the wall as shown in the figure. The reaction forces of the wall and the floor respectively are:
1. 30.4 N and 198 N
2. 199 N and 30 N
3. 30 N and 199 N
4. 34.6 N and 199 N
A metal bar 70 cm long and 4.00 kg in mass supported on two knife edges placed 10 cm from each end. A 6.00 kg load is suspended at 30 cm from one end as shown in the figure. The reactions at the knife-edges are:
(Assume the bar to be of uniform cross-section and homogeneous.)
1. 43.12 N and 54.88 N
2. 54.88 N and 4.312 N
3. 54.88 N and 43.12 N
4. 43.12 N and 5.488 N
Moment of a couple:
1. | depends on the point about which you take the moments. |
2. | depends on the reference frame. |
3. | does not depend on the point about which you take the moments. |
4. | does not depend on the direction of the forces. |
The angular momentum about any point of a single particle moving with constant velocity:
1. increases continuously.
2. decreases continuously.
3. first increases then decrease.
4. remains constant throughout the motion.
If the force \(7\hat i+3\hat j-5\hat k\) acts on a particle whose position vector is \(\hat i - \hat j+\hat k\), the torque of the force about the origin is?
1. \(2\hat i +12\hat j+10\hat k\)
2. zero
3. \(2\hat i -12\hat j-10\hat k\)
4. \(2\hat i +12\hat j-10\hat k\)
What is the position of centre of mass of a uniform L-shaped lamina (a thin flat plate) with dimensions as shown? The mass of the lamina is 3 kg.
1. | \(\left(\dfrac{6}{5} , \dfrac{6}{5}\right)\) | 2. | \(\left(\dfrac{1}{5} , \dfrac{6}{5}\right)\) |
3. | \(\left(\dfrac{5}{6} , \dfrac{5}{6}\right)\) | 4. | Can't be determined |