Question

PART: A (20 x 4 = 80 Marks) (4R-1W)
CHOOSE THE SINGLE CORRECT OPTION:
1. The magnitudes of four pairs of displacement vectors are given. Which pairs of displacement
vectors cannot be added to give a resultant vector of magnitude 4cm?
(A) 2cm, 3cm (B) 1cm, 3cm (C) 1cm, 5cm (D) 1cm, 7cm
2. Two forces each of 20N act on a body at 120°. The magnitude and direction of the resultant is
(A) 20N: 0= 60° (B) 20/2N : 0 = 60° (C) 10/2N : 0 = 0° (D) 10/2N : 0 = 120°
3. Two forces whose magnitudes are in the ratio 3.5 give a resultant of 35N, if the angle between
them is 60°, the magnitude of each force is
(A) 3N, 5N
(B) 9N, 25N
(C) 15N, 25N (D) 21N, 35N
4. Three forces F1 = 2i+j-KN, F2 = 2i +3j - 3KN, F3 = ai+-k)N act simultaneously on a
particle. The value of 'a' so that particle is in equilibrium?
(A) 4
(B)-4
(C) 2
(D) 6
5. Two forces of 1 N and PN act at a point so that the magnitude of resultant is 1 N and it is
perpendicular to 1 N. The value of P in newtons and the angle between the 1 N and P N are
(A) 2. 135° (B) 13. 120°
(C) 1 450
(D) 2. 150°
6. The unit vector in the direction of resultant of two vectors with components (2, 4,-5) and (1,2,3) is
31 +61 +2k 3i+67+2k 3i 6j 2K
(A)
3i+6i- 2k
(B)
(C)
(D)
49
7
7 7 7
49
7. A particle is moving eastwards with a velocity 5 ms, changes its direction northwards and
moves with same magnitude of velocity. The change in velocity is
(A) zero
(B) ms towards N-E
V2
10
10
(C) ms-* towards S-E
(D)
towards N-W
V2
2
8. A force of 10 N is resolved into the perpendicular components. If the first component makes
30° with the force the magnitudes of the components are (Rectangular components)
(A) 5N, 5N
(B) 52N 5N (C) 5/3N, 5N
(D) 10N, 10/30
10
ms​

Answer 1

1. D
2. A
3. C
4. B
5. A
6. 3i/7+6j/7-2k/7
7. D
8. C

so bro plz mark it as brainlest anz