The value of the unit vector, which is perpendicular to both \(A=\hat{i} + 2\hat{j} + 3 \hat{k}\) and \(B= \hat{i} - 2\hat{j} - 3 \hat{k}\) is equal to:

1. \(\frac{\hat{i}   +   2 \hat{j}   +   3 \hat{k}}{6}\)
2. \(\frac{6\hat{j} -4 \hat{k}}{\sqrt{52}}\)
3. \(\frac{6\hat{j} +4 \hat{k}}{\sqrt{52}}\)
4. \(\frac{2\hat{i} - \hat{j}}{\sqrt{5}}\)

Subtopic:  Vector Product |
 69%
Level 2: 60%+
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The area of a blot of ink, \(A\), is growing such that after \(t\) seconds, \(A=\left(3t^2+\frac{t}{5}+7\right)\text{m}^2\). Then the rate of increase in the area at \(t = 5~\text{s}\) will be:
1. \(30.1~\text{m}^2/\text{s}\)
2. \(30.2~\text{m}^2/\text{s}\)
3. \(30.3~\text{m}^2/\text{s}\)
4. \(30.4~\text{m}^2/\text{s}\)

Subtopic:  Differentiation |
 80%
Level 1: 80%+
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The current in a circuit is defined as I=dqdt. The charge (q) flowing through a circuit, as a function of time (t), is given by q=5t2-20t+3. The minimum charge flows through the circuit at:
1. \(t = 4~\text{s}\)

2. \(t = 2~\text{s}\)

3. \(t = 6~\text{s}\)

4. \(t = 3~\text{s}\)

Subtopic:  Differentiation |
 86%
Level 1: 80%+
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If a vector is inclined at angles \(\alpha ,\beta ,~\text{and}~\gamma\)with \(x\), \(y\), and \(z\)-axis respectively, then the value of \(\sin^{2}\alpha+\sin^{2}\beta+ \sin^{2}\gamma\)
is equal to:

1. \(0\)

2. \(1\)

3. \(2\)

4. \(\frac{1}{2}\)

Subtopic:  Trigonometry |
 56%
Level 3: 35%-60%
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If \(\overrightarrow {A}\) and \(\overrightarrow{B}\) are two vectors inclined to each other at an angle \(\theta,\) then the component of \(\overrightarrow {A}\) perpendicular to \(\overrightarrow {B}\) and lying in the plane containing \(\overrightarrow {A}\) and \(\overrightarrow {B}\) will be:
1. \(\frac{\overrightarrow {A} \overrightarrow{.B}}{B^{2}} \overrightarrow{B}\)
2. \(\overrightarrow{A}   -   \frac{\overrightarrow{A} \overrightarrow{.B}}{B^{2}} \overrightarrow{B}\)
3. \(\overrightarrow{A} -\overrightarrow{B}\)
4. \(\overrightarrow{A} + \overrightarrow{B}\)

Subtopic:  Scalar Product |
 51%
Level 3: 35%-60%
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If \(\left|\overrightarrow A\right|\ne \left|\overrightarrow B\right|\) and \(\left|\overrightarrow A \times \overrightarrow B\right|= \left|\overrightarrow A\cdot \overrightarrow B\right|\), then: 

1.  \(\overrightarrow A \perp \overrightarrow B\)
2. \(\overrightarrow A ~|| ~\overrightarrow B\)
3. \(\overrightarrow A\) is antiparallel to \(\overrightarrow B\)
4. \(\overrightarrow A\) is inclined to \(\overrightarrow B\) at an angle of \(45^{\circ}\) 

Subtopic:  Vector Product |
 68%
Level 2: 60%+
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Two forces of the same magnitude are acting on a body in the East and North directions, respectively. If the body remains in equilibrium, then the third force should be applied in the direction of:

1. North-East

2. North-West

3. South-West

4. South-East

Subtopic:  Resultant of Vectors |
 73%
Level 2: 60%+
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Given are two vectors, \(\overrightarrow{A} =   \left(\right. 2 \hat{i}   -   5 \hat{j}   +   2 \hat{k} \left.\right)\) and \(\overrightarrow{B} =   \left(4 \hat{i}   -   10 \hat{j}   +   c \hat{k} \right).\) What should be the value of \(c\) so that vector \(\overrightarrow A \) and \(\overrightarrow B\) would becomes parallel to each other?
1. \(1\)
2. \(2\)

3. \(3\)

4. \(4\)

Subtopic:  Vector Product |
 70%
Level 2: 60%+
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A block of weight \(W\) is supported by two strings inclined at \(60^{\circ}\) and \(30^{\circ}\) to the vertical. The tensions in the strings are \(T_1\) and \(T_2\) as shown. If these tensions are to be determined in terms of \(W\) using the triangle law of forces, which of these triangles should you draw? (block is in equilibrium):

                                 

1. 2.
3. 4.
Subtopic:  Resultant of Vectors |
 62%
Level 2: 60%+
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The magnitude of the resultant of two vectors of magnitude \(3\) units and \(4\) units is \(1\) unit. What is the value of their dot product?

1. \(-12\) units

2. \(-7\) units

3. \(-1\) unit

4. \(0\)

Subtopic:  Scalar Product |
 73%
Level 2: 60%+
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