A block of mass 10 kg is placed on a rough horizontal surface with a coefficient of friction µ = 0.5. If a horizontal force of 100 N acts on the block, then the acceleration of the block will be:
1. 10 m/s2
2. 5 m/s2
3. 15 m/s2
4. 0.5 m/s2
The maximum speed that can be achieved without skidding by a car on a circular unbanked road of radius R and coefficient of static friction μ, is
1.
2.
3.
4.
A car of mass \(m\) is moving on a level circular track of radius \(R\). If \(\mu_s\) represents the static friction between the road and tyres of the car, the maximum speed of the car in circular motion is given by:
| 1. | \(\sqrt{\dfrac{Rg}{\mu_s} }\) | 2. | \(\sqrt{\dfrac{mRg}{\mu_s}}\) |
| 3. | \(\sqrt{\mu_s Rg}\) | 4. | \(\sqrt{\mu_s m Rg}\) |
| 1. | \(0.1\) | 2. | \(0.2\) |
| 3. | \(0.3\) | 4. | \(0.4\) |
| Assertion (A): | It is difficult to move a bicycle along a road with its brakes on. |
| Reason (R): | When a bicycle moves with its brakes on, it skids and sliding friction is greater than rolling friction. |
| 1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
| 2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
| 3. | (A) is True but (R) is False. |
| 4. | Both (A) and (R) are False. |
| 1. | \(m=10~\text{kg}\) | 2. | \(m=2~\text{kg}\) |
| 3. | \(m=12~\text{kg}\) | 4. | \(m=8~\text{kg}\) |
| 1. | \(\dfrac{2}{3}\) | 2. | \(\dfrac{3}{2}\) |
| 3. | \(\dfrac{1}{2}\) | 4. | \(\dfrac{1}{3}\) |
| 1. | \(10 ~\text{ms}^{-2}\) | 2. | \(0.25 ~\text{ms}^{-2}\) |
| 3. | \(2.5 ~\text{ms}^{-2}\) | 4. | \(25 ~\text{ms}^{-2}\) |