VIDYA CLASSES
For: - JEE/NEET/Ⅺ/Ⅻ(C.B.S.E & B.S.E.B) DPP:-02
Vector: -vector, addition, unit vectormagnitude & direction
1. The magnitude of vectors 𝐴⃗ , 𝐵
⃗⃗ and 𝐶⃗ are 3,4 and 5 unit respectively. If 𝐴⃗ + 𝐵
⃗⃗
= 𝐶⃗ , the angle between 𝐴⃗ and 𝐵⃗⃗ is :-
𝜋
(a) (b) cos−1 (0.6)
2
7 𝜋
(c) tan−1 (d)
5 4
2. A person goes 10km in north and 20km east. What will be displacement from
initial point
(a) 22.36 km (b) 2 km
(c) 5 km (d) 20 km
3. Two forces, each of magnitude F have a resultant of the same magnitude F.
the angle between the two force is :-
(a) 45° (b) 120°
(c) 150° (d) 60°
4. The resultant of two vector A and B is perpendicular to the vector A and it’s
magnitude is equal to half the magnitude of the vector B. The angle between
A and B is:-
(a) 120° (b) 150°
(c) 135° (d) none of these
5. If |𝐴⃗ + 𝐵
⃗⃗| = |𝐴⃗| + |𝐵
⃗⃗|, angle between 𝐴⃗ and 𝐵⃗⃗ will be:-
(a) 90° (b) 120°
(c) 0° (d) 60°
6. Two equal forces ( P each ) act at a point inclined to each other at an angle of
120° . The magnitude of their resultant is :-
(a) P/2 (b) P/4
(c) P (d) 2P
7. If a particle moves from point P(3,4,5) It’s displacement vector be:-
(a) 𝐼̂ + 𝐽̂ + 10𝑘̂ (b) 𝐼̂ + 𝐽̂ + 5𝑘̂
(c) 𝐼̂ + 𝐽̂ (d) 2𝐼̂ + 4𝐽̂ + 6𝑘̂
8. If 𝐴⃗ = 3𝐼̂ + 4𝐽̂ and 𝐵
⃗⃗ = 7𝐼̂ + 24𝐽̂ , the vector having the same magnitude as
B and parallel to A is :-
(a) 50𝐼̂ + 20𝐽̂ (b) 15𝐼̂ + 10𝐽̂
(c) 20𝐼̂ + 15𝐽̂ (d) 15𝐼̂ + 20𝐽̂
9. The unit vector parallel to the resultant of the vector 𝐴⃗ = 4𝐼̂ + 3𝐽̂ + 6𝐾
̂ and
⃗⃗ = −𝐼̂ + 3𝐽̂ − 8𝐾
𝐵 ̂ is:-
1 1
(a) (6𝐼̂ + 6𝐽̂ − 2𝐾
̂ (b) (3𝐼̂ + 6𝐽̂ − 2𝐾
̂
7 7
1 1
(c) (3𝐼̂ + 6𝐽̂ − 2𝐾
̂ (d) (63 − 6𝐽̂ + 2𝐾
̂
49 49
10. Unit vector parallel to the resultant of 𝐴⃗ = 4𝐼̂ − 3𝐽̂ and 𝐵
⃗⃗ = 8𝐼̂ + 8𝐽̂ will be
24𝐼̂+5𝐽̂ 12𝐼̂+5𝐽̂
(a) (b)
13 13
6𝐼̂+5𝐽̂
(c) (d) none of these
13
11. The three vector 𝐴⃗ = 3𝐼̂ − 2𝐽̂ + 𝐾̂ and 𝐵 ̂ and 𝐶⃗ = 2𝐼̂ + 𝐽̂ −
⃗⃗ = 𝐼̂ − 3𝐽̂ + 5𝐾
4𝐾̂
(a) An equilateral triangle (b) isosceles triangle
(c) A right-angle triangle (d) No triangle.
12. The angle which a vector 𝐼̂ + 𝐽̂ + √2𝐾 ̂ makes with x, y and z axes respectively
are:-
(a) 60° , 60° , 60° (b) 45° , 45° , 45°
(c) 60° , 60° , 45° (d) 45° , 45° , 60°
1.(a) 2.(a) 3.(b) 4.(b) 5.(c) 6.(c)
7.(c) 8.(d) 9.(b) 10.(b) 11.(c) 12.(c)
