Two trains travelling on the same track are approaching each other with equal speeds of \(40\ \text{m/s}\). The drivers of the trains begin to decelerate simultaneously when they are just \(2.0\ \text{km}\) apart. Assuming the decelerations to be uniform and equal, the value of the deceleration to barely avoid collision should be:

1. \(11.8\ \text{m/s}^2\)
2. \(11.0\ \text{m/s}^2\)
3. \(1.6\ \text{m/s}^2\)
4. \(0.8\ \text{m/s}^2\)

Subtopic:  Uniformly Accelerated Motion |
Level 3: 35%-60%
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A body moves from rest with a constant acceleration of \(5\ \text{m/s}^2\). Its instantaneous speed (in m/s) at the end of \(10\ \text{s}\) is  

1. \(50\)
2. \(5\)
3. \(2\)
4. \(0.5\)

Subtopic:  Instantaneous Speed & Instantaneous Velocity |
 86%
Level 1: 80%+
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A body starts from rest. What is the ratio of the distance travelled by the body during the \(4^{th}\) and \(3^{rd}\) second:

1. \(\dfrac 75\)

2. \(\dfrac 57\)

3. \(\dfrac 73\)

4. \(\dfrac 37\)

Subtopic:  Uniformly Accelerated Motion |
 86%
Level 1: 80%+
PMT - 1993
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The acceleration \(a\) in m/s2 of a particle is given by a=3t2+2t+2 where t is the time. If the particle starts out with a velocity, \(u=2\) m/s at t = 0, then the velocity at the end of \(2\) seconds will be:
1. \(12\) m/s
2. \(18\) m/s
3. \(27\) m/s
4. \(36\) m/s

Subtopic:  Acceleration |
 75%
Level 2: 60%+
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A particle moves along a straight line such that its displacement at any time \(t\) is given by \(S = t^{3} - 6 t^{2} + 3 t + 4\) metres. The velocity when the acceleration is zero is:
1. \(4\) ms-1
2. \(-12\) ms−1
3. \(42\) ms−1
4. \(-9\) ms−1

Subtopic:  Acceleration |
 83%
Level 1: 80%+
PMT - 1994
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If a body starts from rest and travels \(120\ \text{cm}\) in the \(6^{th}\) second, then what is the acceleration:

1. \(0.20\ \text{m/s}^2\)
2. \(0.027\ \text{m/s}^2\)
3. \(0.218\ \text{m/s}^2\)
4. \(0.03\ \text{m/s}^2\)

Subtopic:  Uniformly Accelerated Motion |
 81%
Level 1: 80%+
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If a car at rest accelerates uniformly to a speed of \(144\ \text{km/h}\) in \(20\ \text{s}\). Then it covers a distance of:

1. \(20\ \text{m}\)
2. \(400\ \text{m}\)
3. \(1440\ \text{m}\)
4. \(2880\ \text{m}\)

Subtopic:  Uniformly Accelerated Motion |
 79%
Level 2: 60%+
PMT - 1997
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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 |
 86%
Level 1: 80%+
PMT - 1997
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If a train travelling at \(72\ \text{km/h}\) is to be brought to rest in a distance of \(200\) metres, then its retardation should be:

1. \(20\ \text{ms}^{–2}\)
2. \(10\ \text{ms}^{–2}\)
3. \(2\ \text{ms}^{–2}\)
4. \(1\ \text{ms}^{–2}\) 

Subtopic:  Uniformly Accelerated Motion |
 82%
Level 1: 80%+
PMT - 2004
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The displacement of a particle starting from rest (at \(t = 0\)) is given by \(𝑠 = 6 𝑡^ 2 − 𝑡^ 3\). The time in seconds at which the particle will attain zero velocity again is:  

1. \(2\)
2. \(4\)
3. \(6\)
4. \(8\)

Subtopic:  Instantaneous Speed & Instantaneous Velocity |
 80%
Level 1: 80%+
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