If \(F=\alpha t^2-\beta t \) is the magnitude of the force acting on a particle at an instant \(t,\) then the time at which the force becomes constant is (where \(\alpha \) and \(\beta \) are constants):
1. \(\dfrac{\beta}{\alpha}\) 2. \(\dfrac{\beta}{2\alpha}\)
3. \(\dfrac{2\beta}{\alpha}\) 4. zero

Subtopic:  Differentiation |
 69%
Level 2: 60%+
NEET - 2024
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If \(\vec F=2\hat i+\hat j-\hat k\) and \(\vec r=3\hat i+2\hat j-2\hat k,\) then the scalar and vector products of \(\vec F\) and \(\vec r\) have the magnitudes, respectively, as:
1. \(5, ~\sqrt3\)
2. \(4,~ \sqrt5\)
3. \(10, ~\sqrt2\)
4. \(10,~2\)
Subtopic:  Vector Product |
 75%
Level 2: 60%+
NEET - 2022
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The scalar and vector product of two vectors, a=3i^-4j^+5k^ and b=-2i^+j^-3k^ is equal to:

1. \(-25\)7i^-j^-5k^

2. \(25\)-7i^+j^-5k^

3. \(0\)-7i^+j^+3k^

4. \(-25\)-7i^+j^+5k^

Subtopic:  Vector Product |
 75%
Level 2: 60%+
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The magnitude of the resultant of two forces \(A=8~\text{N}\) and \(B=6~\text{N}\) acting at a point angle of \(90^{\circ}\) between them is:
1. \(14~\text{N}\)
2. \(2~\text{N}\)
3. \(10~\text{N}\)
4. \(12~\text{N}\)

Subtopic:  Resultant of Vectors |
 85%
Level 1: 80%+
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The angle between \(\mathrm{A}=\hat{\mathbf{i}}+\hat{\mathbf{j}}\) and \(\mathrm{B}=\hat{\mathbf{i}}-\hat{\mathbf{j}}\) is:
1. \(45^{\circ} \)
2. \(90^{\circ} \)
3. \(-45^{\circ} \)
4. \(180^{\circ}\)
Subtopic:  Scalar Product |
 78%
Level 2: 60%+
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For two vectors \(\vec A\) and \(\vec B\), |\(\vec A\)+\(\vec B\)|=|\(\vec A\) - \(\vec B\)| is always true when:

(a) |\(\vec A\)| = |\(\vec B\)|  ≠ \(0\)
(b) \(\vec A\perp\vec B\)
(c) |\(\vec A\)| = |\(\vec B\)|  ≠ \(0\) and \(\vec A\) and \(\vec B\) are parallel or antiparallel.
(d) when either |\(\vec A\)| or |\(\vec B\)| is zero.

Choose the correct option from the given ones:
1. (a), (d)
2. (b), (c)
3. (b), (d)
4. (a), (b)
Subtopic:  Resultant of Vectors |
 55%
Level 3: 35%-60%
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It is found that \(|\vec{A}+\vec{B}|=|\vec{A}|\). This necessarily implies:

1. \(\vec{B}=0\)
2. \(\vec{A},\) \(\vec{B}\) are antiparallel
3. \(\vec{A}\) and \(\vec{B}\) are perpendicular
4. \(\vec{A}.\vec{B}\leq0\)

Subtopic:  Scalar Product |
Level 4: Below 35%
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Three vectors \(A,B\) and \(C\) add up to zero. Then:
1. vector \((A\times B)\times C\) is not zero unless vectors \(B\) and \(C\) are parallel.
2. vector \((A\times B).C\) is not zero unless vectors \(B\) and \(C\) are parallel.
3. if vectors \(A,B\) and \(C\) define a plane, \((A\times B)\times C\) is in that plane.
4. \((A\times B). C= |A||B||C|\rightarrow C^2= A^2+B^2\)

The incorrect statement/s is/are:
1. (b), (d)
2. (a), (c)
3. (b), (c), (d)
4. (a), (b)

Subtopic:  Vector Product |
Level 3: 35%-60%
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Consider the quantities of pressure, power, energy, impulse, gravitational potential, electric charge, temperature, and area. Out of these, the only vector quantities are:

1. impulse, pressure, and area
2. impulse and area
3. area and gravitational potential
4. impulse and pressure

Subtopic:  Scalars & Vectors |
Level 3: 35%-60%
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The component of a vector \(\vec{r}\) along the X-axis will have maximum value if:

1. \(\vec{r}\) is along the positive Y-axis.
2. \(\vec{r}\) is along the positive X-axis.
3. \(\vec{r}\) makes an angle of \(45^\circ\) with the X-axis.
4. \(\vec{r}\) is along the negative Y-axis.

Subtopic:  Resolution of Vectors |
 70%
Level 2: 60%+
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