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
Hints
Links

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%+
Hints
Links

In a two-dimensional motion, instantaneous speed \(v_0\) is a positive constant. Then which of the following is necessarily true?

1. The average velocity is not zero at any time.
2. The average acceleration must always vanish.
3. The displacements in equal time intervals are equal.
4. Equal path lengths are traversed in equal intervals.
Subtopic:  Speed & Velocity |
 52%
Level 3: 35%-60%
Hints
Links

advertisementadvertisement

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
Hints
Links

If three coordinates of a particle change according to the equations \(x = 3 t^{2}, y = 2 t , z= 4\), then the magnitude of the velocity of the particle at time \(t=1\) second will be:
1. \(2\sqrt{11}~\text{unit}\)
2. \(\sqrt{34}~\text{unit}\)

3. \(40~\text{unit}\)
4. \(2\sqrt{10}~\text{unit}\)

Subtopic:  Speed & Velocity |
 83%
Level 1: 80%+
Hints
Links