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A particle has a displacement of 12 m towards east and 5 m towards north then 6 m vertically upward. The sum of this displacement is

1) 12 m 2) 10.04 m 3) 14.31 m 4) None of these Answer: 3) 14.31 m Solution: Given A particle has a displacement of 12 m towards... View Article

Forces F₁ and F₂ act on a point mass in two mutually perpendicular directions. The resultant force on the point mass will be

1) F1 + F2 2) F1 - F2 3) 4) F12 + F22 Answer: 3) Solution: The resultant is given by (cos 900 = 0)... View Article

Two equal forces are acting at a point with an angle of 60° between them. If the resultant force is equal to 40√3 N, the magnitude of each force is

1) 40 N 2) 20 N 3) 80 N 4) 30 N Answer: 1) 40 N Solution: Given The forces are equal. Therefore, F1 = F2 = F Resultant, R = 40√3 N θ =... View Article

Two force of 12N and 8N act upon a body. The resultant force on the body has maximum value of

1) 4 N 2) 0 N 3) 20 N 4) 8 N Answer: 3) 20 N Solution: When 12N and 8N forces act upon a body the resultant force on the body is... View Article

Two forces, each of magnitude F have a resultant of the same magnitude F. The angle between the two forces is

1) 45° 2) 120° 3) 150° 4) 60° Answer: 2) 120° Solution: R = √{A² + B² + 2A.Bcos} According to the... View Article

Angular momentum is

1) A scalar 2) A polar vector 3) An axial vector 4) None of these Answer: 3) An axial vector Solution: Axial vector does not change... View Article

A hall has the dimensions 10 m × 12 m × 14 m. A fly starting at one corner ends up at a diagonally opposite corner. What is the magnitude of its displacement?

1) 17 m 2) 26 m 3) 36 m 4) 21 m Answer: 4) 21 m Solution: The dimension of the hall is 10 m × 12 m × 14 m The... View Article

A force of 5 N acts on a particle along a direction making an angle of 60° with vertical. Its vertical component will be

1) 10 N 2) 3 N 3) 4 N 4) 2.5 N Answer: 4) 2.5 N Solution: The component of force is vertical direction = F cosθ = F cos 600 =... View Article

Dot product of two mutual perpendicular vector is

1) 0 2) 1 3) ∞ 4) None of these Answer: 1) 0 Solution: The angle between the two vectors is 900 Therefore, a.b = |a||b|cos 900... View Article

A scooter going due East at 10 ms^–1 turns right through an angle of 90⁰. If the speed of the scooter remains unchanged in taking turn, the change is the velocity of the scooter is

1) 20.0 ms–1 South Eastern direction 2) Zero 3) 10.0 ms–1 in Southern direction 4) 14.14 ms–1 in South-West direction Answer: 4) 14.14... View Article

The resultant of two vectors A and B is perpendicular to vector A and its magnitude is equal to half the magnitude of vector B. The angle between A and B is

1) 120° 2) 150° 3) 135° 4) None of these Answer: 2) 150° Solution: The magnitude of resultant of A and B is given by,... View Article

Which pair of the following forces will never give a resultant force of 2 N?

1) 2 N and 2 N 2) 1 N and 1 N 3) 1 N and 3 N 4) 1 N and 4 N Answer: 4) 1 N and 4 N If two vectors A and B are given then the range of... View Article

The sum of two forces acting at a point is 16 N. If the resultant force is 8 N and its direction is perpendicular forces are to smaller force, then the forces are

1) 6N and 10N 2) 8N and 8N 3) 4N and 12N 4) 2N and l4N Answer: 1) 6N and 10N Solution: Let A be the force of smaller magnitude and B... View Article

If the sum of two unit vectors is a unit vector, then the magnitude of the difference is

1) √2 2) √3 3) 1/√2 4) √5 Answer: 2) √3 Solution: Let be the two unit... View Article

A man crosses a 320 m wide river perpendicular to the current in 4 mm. If in still water he can swim with a speed 5/3 times that of the current, then the speed of the current, in m/min is

1) 30 2) 40 3) 50 4) 60 Answer: 4) 60 Solution: Width of the river, d = 320 m Speed of man, v = (5/3)u Speed of current = u u = 60 m/min... View Article

The sum of the magnitudes of two forces acting at a point is 18 and the magnitude of their resultant is 12. If the resultant is at 90o with a force of smaller magnitude, what are the magnitudes of forces?

1) 2, 5 2) 14, 4 3) 5, 13 4) 10, 8 Answer: 3) 5, 13 Solution: Let P be the smaller force and Q be the greater force. Then P+Q=18... View Article