Classical Mechanics | MCQs

Explanation

Explanation

In projectile motion, the velocity is maximum at the point of projection and just before hitting the ground,

Because that’s where the full initial speed is present (both vertical and horizontal components).

At the highest point, the vertical component becomes zero,

And only the horizontal velocity remains, so the overall speed is less than at the point of projection.

Explanation

Centripetal force acts perpendicular to the direction of motion in circular motion.

Since work = force × displacement × cos(θ), and θ = 90°, the work done is zero.

Explanation

In circular motion, the centripetal force  𝐹 required to keep an object moving in a circular path is given by the formula:

𝐹= 𝑚 𝑣^2/ 𝑟

Where:

m is the mass of the object,

v is the velocity of the object,

r is the radius of the circular path.

If the velocity v is doubled, the centripetal force becomes:

F ′ =  m(2v) ^2/r = 4mv ^2/r =4F

This means that if the velocity is doubled, the force will be four times the original, not twice or half the original.

Therefore, neither of the options provided is correct.

Explanation

If the initial velocity is 40 m/s, time is 5 seconds, and acceleration is 10 m/s2, then the distance traveled is 325.

Explanation

If the mass is doubled, both angular and linear momentum will be doubled according to the conservation of momentum principle.

Explanation

If the radius is doubled and the angular velocity remains constant, the tangential acceleration will be unchanged.

Explanation

If the lift is accelerated downward, the apparent weight experienced by an object inside the lift is m(g−a).

Explanation

“Elaborate with examples, the first law of motion” indicates comprehension.