The magnitudes of forces \(\vec F_A\)​​ and \(\vec F_B\)​​ are \(400~\text{N}\) and \(300~\text{N},\) respectively, as shown in the diagram. What is the magnitude of the net force in each of the three given cases?

1. In Case \(1\), the net force is \(100~\text{N}\); Case \(2\), \(700~\text{N}\); and Case \(3\)\(500~\text{N}.\)
2. In Case \(1\), the net force is \(700~\text{N}\); Case \(2\)\(100~\text{N}\); and Case \(3\), \(500~\text{N}.\)
3. In Case \(1\), the net force is \(350~\text{N}\); Case \(2\), \(50~\text{N}\); and Case \(3\), \(450~\text{N}.\)
4. In Case \(1\), the net force is \(350~\text{N}\); Case \(2\), \(50~\text{N}\), and Case \(3\), \(550~\text{N}.\)
Subtopic:  Resultant of Vectors |
 90%
Level 1: 80%+
Please attempt this question first.
Hints
Please attempt this question first.

If \(\vec a\) and \(\vec{b}\) makes an angle \(\cos ^{-1}\left(\frac{5 }{ 9}\right) \) with each other, then \(|\vec{a}+\vec{b}|=\sqrt{2}|\vec{a}-\vec{b}|\) for \(|\vec{a}|=n|\vec{b}|\) The integer value of \(n\) is:
1. \(4\)
2. \(3\)
3. \(2\)
4. \(1\)
Subtopic:  Resultant of Vectors |
 83%
Level 1: 80%+
Please attempt this question first.
Hints

If a vector has a magnitude equal to that of \(\vec{A}=4 \hat{i}+3\hat{j}\) and is parallel to \(\vec{B}=4 \hat{i}+3\hat{j},\) then the \(x\) and \(y\) components of this vector in the first quadrant are \(x\) and \(3\) respectively. Then the value of \(x\) is:
1. \(3\)
2. \(4\)
3. \(5\)
4. \(2\)
Subtopic:  Resultant of Vectors |
 86%
Level 1: 80%+
Please attempt this question first.
Hints

advertisementadvertisement

The following diagram shows three vectors in a plane, each with equal magnitudes and separated by angles of \(120^\circ\) from each other.
                       
What arrow best represents the direction of their vector sum?
1. \(\downarrow\)
2. \(\uparrow\)
3. The sum is zero.
4. The diagram is invalid.
Subtopic:  Resultant of Vectors |
 87%
Level 1: 80%+
Please attempt this question first.
Hints
Please attempt this question first.

Three vectors \(\overrightarrow{{OP}}, ~\overrightarrow{{OQ}},\) and \(\overrightarrow{{OR}},\) each of magnitude \({A},\) are positioned as shown in the figure. If the resultant of these three vectors is \({A \sqrt{ x},}\) the value of \({x}\) is:
1. \(7\) 2. \(3\)
3. \(15\) 4. \(11\)
Subtopic:  Resultant of Vectors |
 85%
Level 1: 80%+
Please attempt this question first.
Hints
Please attempt this question first.

The following diagram represents three vectors of equal magnitudes in a plane.

What arrow best represents the direction of the sum of three vectors?
1. \(\rightarrow\) 2. \(\leftarrow\)
3. \(\uparrow\) 4. \(\downarrow\)
Subtopic:  Resultant of Vectors |
 85%
Level 1: 80%+
Please attempt this question first.
Hints
Please attempt this question first.

advertisementadvertisement

Two forces of magnitude \(A\) and \({A\over 2}\) act perpendicular to each other. The magnitude of the resultant force is equal to: 
1. \(\dfrac A2\) 2. \(\dfrac {\sqrt {5}A} { 2}\)
3. \(\dfrac {3A} {2}\) 4. \(\dfrac {5A} {2}\)
Subtopic:  Resultant of Vectors |
 84%
Level 1: 80%+
Please attempt this question first.
Hints
Please attempt this question first.

If the vector sum of two vectors A and B is maximum, then the angle θ between two vectors will be:

1.  0°

2.  30°

3.  45°

4.  60°

Subtopic:  Resultant of Vectors |
 84%
Level 1: 80%+
Hints
Links

Two vectors, each of magnitude \(A,\) are inclined at an angle \( \theta \) to each other. The magnitude of their resultant vector is:
1. \(A \cos ^2 \dfrac{\theta}{2}\) 2. \(2 A \cos \dfrac{\theta}{2}\)
3. \(2 A \cos \theta\) 4. \(A \cos \dfrac{\theta}{2}\)
Subtopic:  Resultant of Vectors |
 84%
Level 1: 80%+
Please attempt this question first.
Hints
Please attempt this question first.

advertisementadvertisement

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 |
 82%
Level 1: 80%+
Hints
Links