In the figure, the coefficient of friction between the floor and body B is 0.1. The coefficient of friction between bodies B and A is 0.2. A force F is applied as shown on B. The mass of A is rn/2 and of B is m.
a. | The bodies will move together if F = O .25 mg |
b. | The A will slip with B if F = 0.5 mg |
c. | The bodies will move together if F = 0.5 mg |
d. | The bodies will be at rest if F = 0.1 mg |
e | The maximum value of F for which the two bodies will move together is 0.45 mg |
Which of the following statement(s) is/are true?
1. (a, b, d, e)
2. (a, c, d, e)
3. (b, c, d)
4. (a, b, c)
The figure shows the position-time graph of a particle of mass \(4\) kg. What is the force on the particle for \(t>4\) s? (Consider one-dimensional motion only).
1. \(0\)
2. \(40~\mathrm{N}\)
3. \(20~\mathrm{N}\)
4. \(10~\mathrm{N}\)
Assertion (A): | A man who falls from a height on a cement floor receives more injury than when he falls from the same height on a heap of sand. |
Reason (R): | The impulse applied by a cement floor is less than the impulse applied by a sand floor. |
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. |
Assertion (A): | A rocket moves forward by pushing the surrounding air backward. |
Reason (R): | It derives the necessary thrust to move forward according to Newton's first law of motion. |
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. |
Assertion (A): | A rocket works on the principle of conservation of linear momentum. |
Reason (R): | Higher is the velocity, smaller is the pressure and vice-versa. |
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. |
Assertion (A): | The driver in a vehicle moving at a constant speed on a straight road is in a non-inertial frame of reference. |
Reason (R): | A reference frame in which Newton's law of motion is applicable is non-inertial. |
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. |
Assertion (A): | A man in a closed cabin, which is falling freely, does not experience gravity. |
Reason (R): | Inertial and gravitational mass have equivalence. |
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. |
Assertion (A): | The principle of rocket propulsion is a special case of a variable mass system. |
Reason (R): | The principle of rocket propulsion can be explained by Newton's second law. |
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. |