CBSE Class 11 Physics Motion in a Plane MCQs Set A

Question: Which of the following conditions are sufficient and essential for a quantity to be a vector?

a) Magnitude, direction, and addition, subtraction multiplication and division by vector laws

b) Magnitude, direction and combination of vectors by ordinary rules of algebra

c) Magnitude and addition, subtraction, multiplication by ordinary rules of algebra

d) Magnitude and direction

Answer: Magnitude, direction, and addition, subtraction multiplication and division by vector laws

Question: How many minimum number of vectors in different planes can be added to give zero resultant?

a) 4

b) 5

c) 3

d) 2

Answer: 4

Question: Acceleration due to gravity

a) polar vector

b) a scalar

c) a vector

d) None of these

Answer: polar vector

Question: The resultant of A × 0 will be equal to

a) zero vector

b) zero

c) A

d) unit vector

Answer: zero vector

Question: Two vectors A and B lie in a plane, a third vector C lies outside this plane, the sum of these vectors A + B + C (a) can be zero

a) can never be zero

b) can be zero

c) Both

d) None of these

Answer: can never be zero

Question: For motion in two or three dimensions, the angle between velocity and acceleration is

a) Any angle between 0° & 180°

b) 180°

c) 90°

d) 0°

Answer: Any angle between 0° & 180°

Question: A particle moves in a plane with a constant acceleration in a direction different from the initial velocity. The path of the particle is a/an

a) parabola

b) straight line

c) arc of a circle

d) ellipse

Answer: parabola

Question: The shape of trajectory of the motion of an object is determined by

a) All of these

b) initial position

c) acceleration

d) initial velocity

Answer: All of these

Question: In the projectile motion, if air resistance is ignored, the horizontal motion is at

a) constant velocity

b) constant retardation

c) constant acceleration

d) variable acceleration

Answer: constant velocity

Question: A bullet is dropped from the same height when another bullet is fired horizontally. They will hit the ground

a) simultaneously

b) depends on the observer

c) None of these

d) one after the other

Answer: simultaneously

Question: A boat crosses a river with a velocity of 8 km/h. If the resulting velocity of boat is 10 km/h then the velocity of river water is

a) 6 km/h

b) 8 km/h

c) 10 km/h

d) 4 km/h

Answer: 6 km/h

Question: A moves with 65 km/h while B is coming back of A with 80 km/h. The relative velocity of B with respect to A is

a) 15 km/h

b) 145 km/h

c) 60 km/h

d) 80 km/h

Answer: 15 km/h

Question: Centripetal acceleration is

a) not a constant vector

b) a magnitude changing vector

c) a constant scalar

d) a constant vector

Answer: not a constant vector

Question: The direction of the angular velocity vector is along

a) the axis of rotation

b) the outward radius

c) the inward radius

d) the tangent to the circular path

Answer: the axis of rotation