The angle which the vector $\overrightarrow{A}=2\hat{i}+3\hat{j}$ makes with the y-axis, where $\hat{i}$ and $\hat{j}$ are unit vectors along x- and y-axis, respectively, is

1. cos^-1 (3/5) 

2. cos^-1 (2/3)

3. tan^-1 (2/3)

4. sin^-1 (2/3)

The components of a vector along the x and y directions are (n + 1) and 1, respectively. If the coordinate system is rotated by an angle θ, then the components change to n and 3. The value of n will be:

1. 2
2. cos 60°
3. sin 60°
4. 3.5

If the magnitude of the sum of two vectors is equal to the magnitude of the difference between the two vectors, the angle between these vectors is:

1. 90°

2. 45° 

3. 180° 

4. 0°

Six vectors $\overrightarrow{a} through \overrightarrow{f}$ have the directions as indicated in the figure. Which of the following statements may be true?

1. $\overrightarrow{b}+\overrightarrow{c}=\overrightarrow{-f}$                       
2. $\overrightarrow{d}+\overrightarrow{c}=\overrightarrow{f}$
3. $\overrightarrow{d}+\overrightarrow{e}=\overrightarrow{f}$                       
4. $\overrightarrow{b}+\overrightarrow{e}=\overrightarrow{f}$

The projection of a vector $\overrightarrow{r}=3\hat{i} + \hat{j} +\hspace{0.17em}2\hat{k}$ on the XY-plane has a magnitude of:

1. \(3\)

2. \(4\)

3. $\sqrt{14}$

4. $\sqrt{10}$

If a vector \(2\hat{i}+3\hat{j}+8\hat{k}\) is perpendicular to the vector \(-4\hat{i}+4\hat{j}+\alpha \hat{k},\) then the value of \(\alpha\) will be:$\mathrm{}$
1. $-1$
2. $-\frac{1}{2}$
3. $\frac{1}{2}$
4. \(1\)

Two forces are such that the sum of their magnitudes is 18 N and their resultant is perpendicular to the smaller force and the magnitude of the resultant is 12 N. Then the magnitudes of the forces will be:

1. 12 N, 6 N

2. 13 N, 5N

3. 10 N, 8 N

4. 16 N, 2 N

Assertion: The graph between P and Q is a straight line when P/Q is constant.
Reason: The straight-line graph means that P is proportional to Q or P is equal to a constant multiplied by Q.

Which one, of the following statements, is correct?
1. If both the assertion and the reason are true, and the reason is the correct explanation of the assertion.
2. If both the assertion and the reason are true but the reason is not the correct explanation of the assertion.
3. If the assertion is true but the reason is false.
4. If the assertion and reason are both false

Given that $\overrightarrow{\mathrm{C} }= \overrightarrow{A } + \overrightarrow{B } \mathrm{and} \overrightarrow{\mathrm{C} }$ makes an angle $\mathrm{\alpha } \mathrm{with} \overrightarrow{\mathrm{A}} \mathrm{and} \mathrm{\beta } \mathrm{with} \overrightarrow{\mathrm{B}}$. Which of the following options is correct?

1.  $\mathrm{\alpha } \mathrm{cannot} \mathrm{be} \mathrm{less} \mathrm{then} \mathrm{\beta }$

2.  $\mathrm{\alpha } <\mathrm{\beta }, \mathrm{if} \mathrm{A}<\mathrm{B}$

3.  $\mathrm{\alpha } <\mathrm{\beta }, \mathrm{if} \mathrm{A}>\mathrm{B}$

4.  $\mathrm{\alpha } <\mathrm{\beta }, \mathrm{if} \mathrm{A}=\mathrm{B}$

Two forces, 1 N and 2 N, act along with the lines x = 0 and y = 0. The equation of the line along which the resultant lies is given by:

1.  y - 2x = 0

2.  2y - x = 0

3.  y + x = 0

4.  y - x = 0