Which graph corresponds to an object moving with a constant negative acceleration and a positive velocity?
1. 2.
3. 4.
Subtopic:  Acceleration |
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The machine as shown has \(2\) rods of length \(1~\text{m}\) connected by a pivot at the top. The end of one rod is connected to the floor by a stationary pivot and the end of the other rod has a roller that rolls along the floor in a slot. As the roller goes back and forth, a \(2~\text{kg}\) weight moves up and down. If the roller is moving towards the right at a constant speed, the weight moves up with a:
1. speed which is \(\frac{3}{4}\text{th}\) of that of the roller when the weight is \(0.4~\text{m}\) above the ground
2. constant speed
3. decreasing speed
4. increasing speed 
Subtopic:  Speed & Velocity |
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Ship \(A\) is sailing towards north-east with velocity \(\vec{v}=30 \hat{i}+50 \hat{j}+50 \hat{i}~ \text{km/hr}\) where \(\hat{i}\) and \(\hat{j}\) north. Ship \(B\) is at a distance of \(80~\text{km}\) east and \(150~\text{km}\) north of Ship \(A\) and is sailing towards west at \(10~\text{km/hr}\). \(A\) will be at minimum distance from \(B\) in:
1. \(4.2~\text{hrs}\)
2. \(2.2~\text{hrs}\)
3. \(2.6~\text{hrs}\)
4. \(3.2~\text{hrs}\)

Subtopic:  Relative Motion |
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The stream of a river is flowing with a speed of \(2~\text{km/h}\). A swimmer can swim at a speed of \(4~\text{km/h}\). What should be the direction of the swimmer with respect to the flow of the river to cross the river straight?
1. \( 60^{\circ} \)
2. \( 90^{\circ} \)
3. \( 150^{\circ} \)
4. \( 120^{\circ}\)

Subtopic:  Relative Motion |
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The position vector of a particle changes with time according to the relation,
\(\vec{r}(t)=(15 t^2) \hat{i}+\left(4-20 t^2\right) \hat{j},\) where \(\vec{r}(t)\) is in metres and \(t\) is in seconds.
What is the magnitude of the acceleration at \(t=1\) second?  
1. \(100\) m/s2 2. \(40\) m/s2
3. \(50\) m/s2 4. \(25\) m/s2
Subtopic:  Acceleration |
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A plane is inclined at an angle \(\alpha =30^\circ\) with respect to the horizontal. A particle is projected with a speed \(u=2~\text{ms}^{-1}\), from the base of the plane, making an angle \(\theta=15^\circ\) with respect to the plane as shown in the figure. the distance from the base, at which the particle hits the plane is close to: (Take \(g= 10\) ms–2)

      
1. \(14~\text{cm}\)
2. \(18~\text{cm}\)
3. \(20~\text{cm}\)
4. \(26~\text{cm}\)

Subtopic:  Projectile Motion |
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A shell is fired from a fixed artillery gun with an initial speed \(u\) such that it hits the target on the ground at a distance \(R\) from it. If \(t_1\) and \(t_2\) are the values of the time taken by it to hit the target in two possible ways, the product \(t_1t_2\) is:
1. \(\frac{2R}{g}\)
2. \(\frac{R}{2g}\)
3. \(\frac{R}{g}\)
4. \(\frac{R}{4g}\)

Subtopic:  Projectile Motion |
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The trajectory of a projectile near the surface of the earth is given as \(y=2x-9x^2\). If it were launched at an angle \(\theta_0\) with speed \(v_0\) then:\(\left(g= 10~\text{ms}^{-2}\right)\)

1. \(\theta_0=\cos^{-1}\left(\frac{1}{\sqrt{5}}\right) \text{ and }v_0=\frac{5}{3}~\text{ms}^{-1}\)
2. \(\theta_0=\cos^{-1}\left(\frac{2}{\sqrt{5}}\right) \text{ and }v_0=\frac{3}{5}~\text{ms}^{-1}\)
3. \(\theta_0=\sin^{-1}\left(\frac{2}{\sqrt{5}}\right) \text{ and }v_0=\frac{3}{5}~\text{ms}^{-1}\)
4. \(\theta_0=\sin^{-1}\left(\frac{1}{\sqrt{5}}\right) \text{ and }v_0=\frac{5}{3}~\text{ms}^{-1}\)
Subtopic:  Projectile Motion |
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Two particles are projected from the same point with the same speed \(u,\) but at different angles. They both cover the same horizontal range \(R,\) but reach different maximum heights, \(h_1\)​ and \(h_2.\) Which of the following relations is correct?
1. \(R^2=h_1h_2\)
2. \(R^2=16h_1h_2\)
3. \(R^2=4h_1h_2\)
4. \(R^2=2h_1h_2\)

Subtopic:  Projectile Motion |
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A particle is moving with a velocity \(\vec v=K(y \hat{i}+x\hat{j}),\) where \(K\) is a constant. The general equation for its path is: 
1. \(y=x^2+\text{constant}\)
2. \(y^2=x+\text{constant}\)
3. \(y^2=x^2+\text{constant}\)
4. \(xy=\text{constant}\)
Subtopic:  Position & Displacement |
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