Vectors (Board Level)

1.

Two vectors \vec{A} and \vec{B} of magnitude a andb are added, the magnitude of the resultant vector \vec{C}is c. Then

(a) (a + b)               (b) (a + b)                 (c) (a + b)               (d) (a + b) 

Ans (b)

2.

The rectangular components of a force of magnitude 5dyne are

(a) 3 and 4 dyne          (b) 2.5 and 25 dyne        (c) 1 and 2 dyne                      (d) 2 and 3 dyne

Ans (a)

3.

If \vec{A}=\vec{B}+\vec{C} and the magnitudes of \vec{A}, \vec{B} and \vec{C} are 5, 4 and 3 unit respectively, the angle between \vec{A} and \vec{C} is

(a) \frac{\pi }{2}                      

(b) {{\sin }^{{-1}}}\left( {\frac{3}{4}} \right)     

(c) {{\cos }^{{-1}}}\left( {\frac{3}{5}} \right)   

(d) {{\cos }^{{-1}}}\left( {\frac{4}{5}} \right)

Ans (c)

4.

Angle between the vectors (\vec{i}+\vec{j}) and (\vec{j}+\vec{k}) is

(a) 60°                         (b) 90°                            (c) 180°                       (d) 0°

Ans (a)

5.

What is the maximum number of components into which a vector can split?

(a) 2                      (b) 3                            (c) 4                          (d) more than 4

Ans (d)

6.

A force of 6 kg and 8 kg can be applied together to produce the effect of a single force of

(a) 20 kg                      (b) 15 kg                         (c) 11 kg                      (d) 1 kg

Ans (c)