In a uniform circular motion, which of the following quantity is not constant

1. Angular momentum

2. Speed

3. Kinetic energy

4. Momentum

Subtopic:  Circular Motion |
 53%
Level 3: 35%-60%
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A particle is moving with velocity \(\vec v=k(y\hat i+x \hat j)\), where \(k\) is constant. The general equation for the path is:

1. \(y=x^2+\text{constant}\)

2. \(y^2=x^2+\text{constant}\)

3. \(y=x+\text{constant}\)

4. \(xy=\text{constant}\)

Subtopic:  Speed & Velocity |
Level 3: 35%-60%
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A projectile is given an initial velocity of \(\hat i+2\hat j\). The cartesian equation of its path is: (Take \(g = 10 \ \text{ms}^{ - 2}\)) 

1. \(y=2x-5x^2\)

2. \(y=x-5x^2\) 

3. \(4y=2x-5x^2\)

4. \(y=2x-25x^2\)

Subtopic:  Projectile Motion |
 59%
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:  Projectile Motion |
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 \(  𝑦 = 𝑏 𝑥^2\). 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:  Acceleration |
Level 3: 35%-60%
Hints

A particle has initial velocity 3i^+4j^ and has acceleration 0.4i^+0.3j^. Its speed after 10 s:

1. 7 units

2. 72 units

3. 8.5 units

4. 10 units

Subtopic:  Uniformly Accelerated Motion |
 79%
Level 2: 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:  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:  Relative Motion |
 85%
Level 1: 80%+
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A boat moves with a speed of \(5\ \text{km/h}\) relative to water in a river flowing with a speed of \(3\ \text{km/h}\) and having a width of \(1\ \text{km}\). The minimum time taken for a round trip (returning to the initial point) is:

1. \(5\ \text{min}\)

2. \(60\ \text{min}\)

3. \(20\ \text{min}\)

4. \(30\ \text{min}\)

Subtopic:  Relative Motion |
 55%
Level 3: 35%-60%
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A river is flowing from W to E with a speed of 5 m/min. A man can swim in still water with a velocity 10 m/min. In which direction should the man swim so as to take the shortest possible path to go to the south. 

1. 30° with downstream

2. 60° with downstream

3. 120° with downstream

4. South

Subtopic:  Relative Motion |
 56%
Level 3: 35%-60%
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