The relation between time and distance is given by \(t=\alpha x^2+\beta x,\) where \(\alpha\) and \(\beta\) are constants. The retardation, as calculated based on this equation, will be (assume \(v\) to be velocity):
1. \(2\alpha v^3\)
2. \(2\beta v^3\)
3. \(2\alpha\beta v^3\)
4. \(2\beta^2 v^3\)

Subtopic:  Instantaneous Speed & Instantaneous Velocity |
 55%
Level 3: 35%-60%
Hints

The displacement of a particle is given by \(y = a + bt + ct^{2} - dt^{4}\). The initial velocity and acceleration are, respectively:

1. \(b, -4d\) 2. \(-b,2c\)
3. \(b, ~2c\) 4. \(2c, -2d\)
Subtopic:  Non Uniform Acceleration |
 83%
Level 1: 80%+
PMT - 1999
Hints
Links

The position \(x\) of a particle varies with time \(t\) as \(x=at^2-bt^3\). The acceleration of the particle will be zero at time \(t\) equal to:

1. \(\dfrac{a}{b}\) 2. \(\dfrac{2a}{3b}\)
3. \(\dfrac{a}{3b}\) 4. zero
Subtopic:  Acceleration |
 85%
Level 1: 80%+
PMT - 1997
Hints
Links

advertisementadvertisement

A student is standing at a distance of \(50\) metres from the bus. As soon as the bus begins its motion with an acceleration of \(1\) ms–2, the student starts running towards the bus with a uniform velocity \(u\). Assuming the motion to be along a straight road, the minimum value of \(u\), so that the student is able to catch the bus is:
1. \(5\) ms–1
2. \(8\) ms–1
3. \(10\) ms–1
4. \(12\) ms–1

Subtopic:  Uniformly Accelerated Motion |
 75%
Level 2: 60%+
Hints
Links

A body starts to fall freely under gravity. The distances covered by it in the first, second and third second will be in the ratio: 

1. \(1:3:5\) 2. \(1:2:3\)
3. \(1:4:9\) 4. \(1:5:6\)
Subtopic:  Uniformly Accelerated Motion |
 87%
Level 1: 80%+
Hints
Links

A particle moving in a straight line covers half the distance with a speed of \(3~\text{m/s}\). The other half of the distance is covered in two equal time intervals with speeds of \(4.5~\text{m/s}\) and \(7.5~\text{m/s}\) respectively. The average speed of the particle during this motion is:
1. \(4.0~\text{m/s}\)
2. \(5.0~\text{m/s}\)
3. \(5.5~\text{m/s}\)
4. \(4.8~\text{m/s}\)

Subtopic:  Average Speed & Average Velocity |
 71%
Level 2: 60%+
Hints
Links

advertisementadvertisement

A stone dropped from a building of height \(h\) and reaches the earth after \(t\) seconds. From the same building, if two stones are thrown (one upwards and other downwards) with the same velocity \(u\) and they reach the earth surface after \(t_1\) and \(t_2\) seconds respectively, then: 

1. t=t1t2

2. t=t1+t22

3. t=t1t2

4. t=t12t22 

Subtopic:  Uniformly Accelerated Motion |
 78%
Level 2: 60%+
PMT - 1997
Hints
Links

The velocity-time \((v\text-t)\) graph of a body moving in a straight line is shown in the figure. The displacement and distance travelled by the body in \(6\) s are, respectively: 

              

1. \(8\) m, \(16\) m
2. \(16\) m, \(8\) m
3. \(16\) m, \(16\) m
4. \(8\) m, \(8\) m

Subtopic:  Graphs |
 80%
Level 1: 80%+
Hints
Links

In the following graph, the distance travelled by the body in metres is:

         

1. \(200\) 2. \(250\)
3. \(300\) 4. \(400\)
Subtopic:  Graphs |
 87%
Level 1: 80%+
Hints
Links

advertisementadvertisement

Given below are two statements: 

Assertion (A): Position-time graph of a stationary object is a straight line parallel to the time axis.
Reason (R): For a stationary object, the position does not change with time.
  
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.
Subtopic:  Distance & Displacement |
 87%
Level 1: 80%+
Hints
Links