A particle is moving such that its position coordinates \((x,y)\) are \(​ (2~\text m,  3~\text m)​\) at time \(t=0,\)  \(​ (6~\text m,  7~\text m)​\) at time \(t=2~\text s\)  and \(​ (13~\text m,  14~\text m)​\) at time \(t=5~\text s.\)  The average velocity vector \((v_{avg})\) from \(t=0\) to \(t=5~\text s\) is:

1. \(\frac{1}{5}\left ( 13\hat{i}+14\hat{j} \right )\) 2. \(\frac{7}{3}\left ( \hat{i}+\hat{j} \right )\)
3. \(2\left ( \hat{i}+\hat{j} \right )\) 4. \(\frac{11}{5}\left ( \hat{i}+\hat{j} \right )\)
Subtopic:  Speed & Velocity |
 83%
Level 1: 80%+
NEET - 2014

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A car turns at a constant speed on a circular track of radius \(100~\text m,\) taking \(62.8~\text s\) for every circular lap. The average velocity and average speed for each circular lap, respectively, is:

1. \(0,~0\) 2. \(0,\)  \(10~\text{m/s},\)
3. \(10~\text{m/s},\) ​​​​​​​ \(10~\text{m/s},\) 4. \(10~\text{m/s},\) \(0\)
Subtopic:  Speed & Velocity |
 83%
Level 1: 80%+
AIPMT - 2006

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The coordinates of a moving particle at any time \(t\) are given by \(x= \alpha t^3\) and \(y = \beta t^3.\) The speed of the particle at a time \(t\) is given by:

1. \(\sqrt{\alpha^{2} + \beta^{2}}\) 2. \(3t \sqrt{\alpha^{2} + \beta^{2}}\)
3. \(3t^{2} \sqrt{\alpha^{2} +\beta^{2}}\) 4. \(t^{2} \sqrt{\alpha^{2} +\beta^{2}}\)
Subtopic:  Speed & Velocity |
 80%
Level 1: 80%+

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Two particles \(A\) and \(B,\) move with constant velocities \(\vec{v_1}\) and \(\vec{v_2}.\) At the initial moment their position vector are \(\vec {r_1}\) and \(\vec {r_2}\) respectively. The conditions for particles \(A\) and \(B\) for their collision to happen will be:

1. \(\vec{r_{1  }} . \vec{v_{1}}   = \vec{r_{2  }} . \vec{v_{2}}\) 2. \(\vec{r_{1}} \times\vec{v_{1}}   = \vec{r_{2}} \times \vec {v_{2}}\)
3. \(\vec{r_{1}}-\vec{r_{2}}=\vec{v_{1}} - \vec{v_{2}}\) 4. \(\frac{\vec{r_{1}} - \vec{r_{2}}}{\left|\vec{r_{1}} -  \vec{r_{2}}\right|} =   \frac{\vec{v_{2}} -  \vec{v_{1}}}{\left|\vec{v_{2}} -   \vec{v_{1}}\right|}\)
Subtopic:  Speed & Velocity |
 72%
Level 2: 60%+

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Two particles move from \(A\) to \(C\) and \(A\) to \(D\) on a circle of radius \(R\) and the diameter \(AB.\) If the time taken by both particles is the same, then the ratio of magnitudes of their average velocities is:
                                
1. \(2\)
2. \(2\sqrt{3}\)

3. \(\sqrt{3}\)
4. \(\dfrac{\sqrt{3}}{2}\)

Subtopic:  Speed & Velocity |
 63%
Level 2: 60%+

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The position of a particle is given by; \(\vec{r}=(3.0t\hat{i}-2.0t^{2}\hat{j}+4.0\hat{k})~\text{m},\) where \(t\) is in seconds and the coefficients have the proper units for \(r\) to be in meters. The magnitude and direction of \(\vec{v}(t)\) at \(t=1.0~\text s\) are:
1. \(4~\text{m/s},\) \(53^\circ\) with \(x\)-axis
2. \(4~\text{m/s},\) ​​​​​​​\(37^\circ\) with \(x\)-axis
3. \(5~\text{m/s},\) \(53^\circ\) with \(y\)-axis
4. \(5~\text{m/s},\) ​​​​​​​ \(53^\circ\) with \(x\)-axis
Subtopic:  Speed & Velocity |
 71%
Level 2: 60%+

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A bus is going to the North at a speed of \(30\) kmph. It makes a \(90^{\circ}\) left turn without changing the speed. The change in the velocity of the bus is:

1. \(30~\text{kmph}\) towards \(\mathrm{W}\)
2. \(30~\text{kmph}\) towards \(\mathrm{S\text-W}\)
3. \(42.4~\text{kmph}\) towards \(\mathrm{S\text-W}\)
4. \(42.4~\text{kmph}\) towards \(\mathrm{N\text-W}\)
Subtopic:  Speed & Velocity |
 60%
Level 2: 60%+

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Three particles are moving with constant velocities \(v_1 ,v_2\) and \(v\) respectively as given in the figure. After some time, if all the three particles are in the same line, then the relation among \(v_1 ,v_2\) and \(v\) is:
                            
1. \(v =v_1+v_2\)
2. \(v= \sqrt{v_{1} v_{2}}\)
3. \(v = \frac{v_{1} v_{2}}{v_{1} + v_{2}}\)
4. \(v=\frac{\sqrt{2} v_{1} v_{2}}{v_{1} + v_{2}}\)

Subtopic:  Speed & Velocity |
 53%
Level 3: 35%-60%

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