The acceleration \(a\) (in ms-2) of a body, starting from rest varies with time \(t\) (in \(\mathrm{s}\)) as per the equation \(a=3t+4.\) The velocity of the body at time \(t=2\) \(\mathrm{s}\) will be:

1. \(10~\text{ms}^{-1}\) 2. \(18~\text{ms}^{-1}\)
3. \(14~\text{ms}^{-1}\) 4. \(26~\text{ms}^{-1}\)

Subtopic:  Non Uniform Acceleration |
 73%
Level 2: 60%+
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A body is thrown vertically up to reach its maximum height in \(t\) seconds. The total time from the time of projection to reach a point at half of its maximum height while returning (in seconds) is:

1. \(\sqrt2\ t\)

2. \(\left(1+\dfrac{1}{\sqrt2}\right)t\)

3. \(\dfrac{3t}{2}\)

4. \(\dfrac{t}{\sqrt2}\)

Subtopic:  Uniformly Accelerated Motion |
 57%
Level 3: 35%-60%
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A stone falls freely from rest from a height \(h\) and it travels a distance \(\dfrac{9h}{25}\) in the last second. The value of \(h\) is: (Take \(g=10\ \text{m/s}^2\))

1. \(145\ \text{m}\)

2. \(100\ \text{m}\)

3. \(125\ \text{m}\)

4. \(200 \ \text{m}\)

Subtopic:  Uniformly Accelerated Motion |
 70%
Level 2: 60%+
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A point moves in a straight line under retardation \(av^2\). If the initial velocity is \(u,\) the distance covered in \(t\) seconds is:
1. \((aut)\)

2. \(\dfrac{1}{a}\mathrm{ln}(aut)\)

3. \(\dfrac{1}{a}\mathrm{ln}(1+aut)\)

4. \(a~\mathrm{ln}(aut)\)

Subtopic:  Non Uniform Acceleration |
 56%
Level 3: 35%-60%
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A particle is thrown upwards from the ground. It experiences a constant resistance force, which can produce retardation of \(2~\text{m/s}^2\). The ratio of the time of ascent to the time of descent is: \([\text{Take} \ g = 10~\text{m/s}^2]\)
1. \(1:1\)
2. \(\sqrt{\frac{2}{3}}\)
3. \(\frac{2}{3}\)
4. \(\sqrt{\frac{3}{2}}\)
Subtopic:  Uniformly Accelerated Motion |
Level 3: 35%-60%
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A bullet loses \(\dfrac{1}{20}\) of its velocity passing through a plank. The least number of planks required to stop the bullet is: (All planks offers same retardation)
1. \(10\)
2. \(11\)
3. \(12\)
4. \(23\)

Subtopic:  Uniformly Accelerated Motion |
 59%
Level 3: 35%-60%
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A body starts from the origin and moves along the X-axis such that the velocity at any instant is given by \( ( 4 𝑡^ 3 − 2 𝑡 )\), where \(t\) is in sec and velocity in m/s. What is the acceleration of the particle when it is \(2\ \text{m}\) from the origin?

1. \(28\ \text{m/s}^2\)

2. \(22\ \text{m/s}^2\)

3. \(12\ \text{m/s}^2\)

4. \(10\ \text{m/s}^2\)

Subtopic:  Non Uniform Acceleration |
 64%
Level 2: 60%+
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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 |
 56%
Level 3: 35%-60%
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A point moves with uniform acceleration, and \(v_1,\ v_2\) and \(v_3\) denote the average velocities in the three successive intervals of time \(t_1,\ t_2\) and \(t_3\). Which of the following relations is correct?

1. \((v_1 - v_2):(v_2 - v_3) = (t_1 - t_2):(t_2 + t_3)\)
2. \((v_1 - v_2):(v_2 - v_3) = (t_1 + t_2):(t_2 + t_3)\)
3. \((v_1 - v_2):(v_2 - v_3) = (t_1 - t_2):(t_2 - t_3)\)
4. \((v_1 - v_2):(v_2 - v_3) = (t_1 + t_2):(t_2 - t_3)\) 

Subtopic:  Uniformly Accelerated Motion |
 52%
Level 3: 35%-60%
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The acceleration of a moving body can be found from: 

1. Area under the velocity-time graph

2. Area under the distance-time graph

3. Slope of the velocity-time graph

4. Slope of the distance-time graph

Subtopic:  Graphs |
 76%
Level 2: 60%+
PMT - 1981
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