NEET Physics: speed and velocity Practice Questions

Correct answer: C — Centripetal acceleration

Even if the speed is constant, the object is constantly changing its direction, resulting in centripetal acceleration directed towards the center of the circle.

Correct answer: B — Change in distance per unit time

Speed is defined as the distance covered divided by the time taken (rate of distance covered).

Correct answer: B — The speed

When motion is in a straight line at a constant speed, the magnitude of the velocity is equal to the speed, and the direction is the direction of motion.

Correct answer: C — 0 km

Displacement is the final position relative to the initial position. Since the motion cancels out (10 km East and 10 km West), the total displacement is zero.

Correct answer: A — Rest

When the velocity is zero, the object is instantaneously at rest, meaning its speed is zero.

Correct answer: D — Velocity

Velocity is the rate of change of displacement and has both magnitude and direction, making it a vector. Distance and speed are scalars, and mass is a scalar.

Correct answer: C — 100 m/s

Velocity is the rate of change of displacement. For one complete round of a circle, the displacement is zero (starting and ending at the same point). Therefore, the average velocity for the entire lap is zero, assuming displacement is the focus. However, if we consider the path length (distance), the speed is constant. In the context of standard introductory kinematics, if the question implicitly asks for the rate of traversing the path, we consider the path length (distance/time). If displacement is strictly considered, velocity is zero. Given the context of simple conceptual recall, the speed (magnitude of velocity) is constant, but since the path is circular, the net displacement is zero.

Correct answer: A — Its velocity is constant

If the speed is constant and the direction is constant (straight line), the velocity is constant. Constant velocity implies zero acceleration.

Correct answer: A — Zero

Velocity is the rate of change of position. If an object is at rest, its position is not changing, thus the rate of change of displacement is zero, meaning its velocity is zero.

Correct answer: C — Acceleration and Velocity

Acceleration and Velocity are vector quantities because they require both magnitude and direction to be fully described. Distance and Speed are scalar quantities.

Correct answer: D — 70.7 meters

When motion is along perpendicular directions (North and East), the displacement is the hypotenuse of the right triangle formed by the two displacements. Displacement = √((50)² + (50)²) = √(2500 + 2500) = √5000 ≈ 70.7 meters.

Correct answer: C — Scalar quantity

Average speed is calculated using distance and time, making it a scalar quantity.

Correct answer: D — Zero

Acceleration is the rate of change of velocity. If velocity is constant (no change in speed or direction), the acceleration is zero.

Correct answer: C — The shortest path between two points

Displacement is the change in position of an object from its initial point to its final point, making it a vector quantity.