Ship A is moving westward with a speed of \(10\ \text{km h}^{- 1}\) and Ship B, \(100 \ \text{km}\)south of A, is moving northwards with a speed of \(10\ \text{km h}^{- 1}\). The time after which the distance between them becomes the shortest is:

1. \(5\) hr

2. \(5 \sqrt2\) hr

3. \(10 \sqrt2\) hr

4. \(0\) hr

Subtopic: Ā Relative Motion |
Level 3: 35%-60%
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The time taken by the projectile to reach from \(A\) to \(B\) is \(t\). Then the distance \(AB\) is equal to :

1. \(\dfrac{ut}{\sqrt3}\)

2. \(\dfrac{\sqrt3ut}{2}\)

3. \(\sqrt3ut\)

4. \(2ut\)

Subtopic: Ā Projectile Motion |
Level 3: 35%-60%
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A particle projected with kinetic energy k0 with an angle of projection θ. Then the variation of kinetic K with vertical displacement y is

1.  linear

2.  parabolic

3.  hyperbolic

4.  periodic

Subtopic: Ā Projectile Motion |
Level 4: Below 35%
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A river is flowing with a speed of \(1\ \text{km/hr}\). A swimmer wants to go to point \(C\) starting from \(A\). He swims with a speed of \(5\ \text{km/hr}\), at an angle \(\theta\)  with respect to the river. If \(\text {AB = BC} = 400\ \text{m}\), then:

 

1. The time taken by the man is \(12\) min

2. The time taken by the man is \(8\) min

3. The value of \(\theta\) is \(45^\circ\)

4. The value of \(\theta\) is \(53^\circ\)

Subtopic: Ā Relative Motion |
Level 3: 35%-60%
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 A body is thrown horizontally with a velocity \(\sqrt{2 g h}\) from the top of a tower of height \(h\). It strikes the level ground through the foot of the tower at a distance \(x\) from the tower. The value of \(x\) is:

1. \( h \) 2. \(\frac{h}{2} \)
3. \(2 h \) 4. \( \frac{2 h}{3}\)
Subtopic: Ā Projectile Motion |
Ā 74%
Level 2: 60%+
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Two men \(P\) and \(Q\) are standing at corners \(A\) and \(B\) of a square \(ABCD\) of side \(8~\text m.\) They start moving along the track with a constant speed \(2~\text{m/s}\) and \(10~\text {m/s}\) respectively. The time when they will meet for the first time is equal to:
       
1. \(2~\text{sec}\)
2. \(3~\text{sec}\)
3. \(1~\text{sec}\)
4. \(6~\text{sec}\) 

Subtopic: Ā Relative Motion |
Ā 58%
Level 3: 35%-60%
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A particle starts from the origin at \(t=0\) and moves in the \(x-y\) plane with constant acceleration \(a\) in the \(y\) direction. Its equation of motion is \(Ā  š‘¦ = š‘ š‘„^2\). The \(x\) component of its velocity \((\text{at} \ t=0) \) is:

1. Variable

2. \(\sqrt{\dfrac{2a}{b}}\)

3. \(\dfrac{a}{2b}\)

4. \(\sqrt{\dfrac{a}{2b}}\)

Subtopic: Ā Acceleration |
Level 3: 35%-60%
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A body is projected with a velocity \(u\) with an angle of projection \(\theta.\) The change in velocity after the time \((t)\) from the time of projection will be:

1. \(gt\) 2. \(\frac{1}{2}gt^2\)
3. \(u\sin\theta\) 4. \(u\cos\theta\)
Subtopic: Ā Projectile Motion |
Ā 55%
Level 3: 35%-60%
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What determines the nature of the path followed by the particle?

1. Speed only

2. Velocity only

3. Acceleration only

4. None of these

Subtopic: Ā Projectile Motion |
Level 3: 35%-60%
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A boat is sent across a river in a perpendicular direction with a velocity of \(8\ \text{km/hr}\). If the resultant velocity of the boat is \(10\ \text{km/hr}\), then the velocity of the river is: 

1. \(10\ \text{km/hr}\)

2. \(8\ \text{km/hr}\) 

3. \(6\ \text{km/hr}\) 

4. \(4\ \text{km/hr}\) 

Subtopic: Ā Relative Motion |
Ā 85%
Level 1: 80%+
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