Explanation

Rotational inertia matters: Sphere has the lowest moment of inertia (I = 2/5 MR²) among sphere, disc (I = 1/2 MR²), and hoop (I = MR²), so it accelerates fastest.

Energy distribution: Less energy goes into rotation → more into translational motion, giving higher speed at the bottom.

Explanation

2 kg absorbed 10 J → 5 J/kg

1 rad = 0.01 J/g = 10 J/kg → 5 ÷ 0.01 = 500 rad.

Explanation

The Sun is a main sequence star, meaning it fuses hydrogen into helium in its core.

It is classified as a G-type (yellow) star in the main sequence phase of its life cycle.

Explanation

Nimbo-stratus clouds are most likely to cause heavy rainfall.

These are thick, dark, and low-lying clouds that often cover the sky. 

They are associated with continuous, steady precipitation.

Explanation

• The Earth is tilted at an angle of 23.5 degrees.
• This tilt is responsible for the changing of the seasons and the difference in the amount of sunlight reaching a given point on the surface during the course of a year.
• The tilt varies between 22.1 and 24.5 degrees in a cycle that averages about 40,000 years.

Explanation

Explanation

During an equinox, the Sun is directly above the Earth’s equator.

At this time, the Earth’s axis is neither tilted toward nor away from the Sun, resulting in equal day and night lengths.

Explanation

When earthquake waves enter the mantle from the crust, their velocity increases.

This happens because the mantle is denser and more rigid, allowing faster wave transmission.

Explanation

The Earth travels around the Sun at an average speed of about 29.8 km/s (≈30 km/s).

This speed keeps Earth in a stable orbit due to the balance between gravity and motion.

Explanation

Waterproof materials prevent water from soaking through due to high surface tension of the coated fabric.

This property causes water to form droplets and roll off instead of being absorbed.