The position (x) of a particle in a straight line motion is given by . Its velocity (v) is best represented by?
1. | 2. | ||
3. | 4. |
A boy falls from a building of height 320 m. After 5 seconds, superman jumps downward with initial speed u such that the boy can be saved. The minimum value of u is (assume g=10 )
1. | 95.1 m/s | 2. | 98.3 m/s |
3. | 91.6 m/s | 4. | 85.6 m/s |
An elevator whose floor to ceiling height is 12 meters, moves upward with an acceleration of . After 1.5 seconds since starting, a bolt falls from its ceiling. The time taken by the bolt to reach the floor is
1. 1 s
2. 2 s
3. s
4. s
The displacement \((x)\) of a point moving in a straight line is given by; \(x=8t^2-4t.\) Then the velocity of the particle is zero at:
1. | \(0.4\) s | 2. | \(0.25\) s |
3. | \(0.5\) s | 4. | \(0.3\) s |
A body is moving along a straight line according to the equation of motion, x, where x is in metre and t is in seconds. What is the acceleration of the body when it comes to rest?
1. Zero
2.
3.
4.
A particle is allowed to fall from rest from a height \(h\). Which of the following represents its velocity versus time graph?
1. | 2. | ||
3. | 4. |
The graph below shows position as a function of time for two trains running on parallel tracks.
Which of the following statements is true?
1. | At time \(t_B \) both the trains have the same velocity |
2. | Both the trains have the same velocity at some time after \(t_B \) |
3. | Both the trains have the same velocity at some time before \(t_B \) |
4. | Both the trains have the same acceleration |
The velocity \(v\) of an object varies with its position \(x\) on a straight line as \(v=3\sqrt{x}.\) Its acceleration versus time \((a\text-t)\) graph is best represented by:
1. | 2. | ||
3. | 4. |
Starting from rest, a car accelerates uniformly at the rate of for some time, then decelerates uniformly at the rate of , and finally comes to rest after a journey of 1 minute. The maximum possible speed of the car during this journey is:
1. 10 m/s
2. 20 m/s
3. 30 m/s
4. 40 m/s
A particle is moving along the x-axis such that its velocity varies with time as per the equation . At t=0 particle is at the origin. From the following, select the correct position (x) - time (t) plot for the particle:
1. | 2. | ||
3. | 4. |