Explanation

In SHM, the total distance covered by a body in one complete oscillation is equal to 4 times the amplitude (A).

Let's break it down:

• The body moves from its equilibrium position to the extreme position (distance = A)
• Then, it moves to the other extreme position (distance = 2A)
• Finally, it returns to the equilibrium position (distance = A) and then to the initial extreme position is not needed as it completes the cycle at the equilibrium position coming from the second extreme, so from the second extreme to equilibrium is A, and from equilibrium to the first extreme is A, totaling 4A for the full cycle.

Explanation

- In solids, molecules are tightly packed and held by strong intermolecular forces, giving solids a definite shape and volume.  

- Gases have the weakest intermolecular forces.

Explanation

Three types of concave lenses:

1. Bi-concave Lens:

This lens has two surfaces that are curved inward, resembling a double concave shape.

It is the most common type of concave lens and diverges light rays symmetrically from both sides. 

2. Plano-concave Lens:

This lens features one flat surface and one concave surface.

The flat side is known as a "plano" surface. 

3. Convexo-Concave Lens:

Also called a menisco-concave lens, this type has one convex (outward-curving) surface and one concave (inward-curving) surface.

For it to be a concave lens, the concave surface must have a greater curvature than the convex surface, which is moving away from the other. 

Explanation

Magnetic lines of force always form closed loops from the north pole to the south pole outside the magnet and continue inside the magnet.

They never start or end abruptly like electric field lines.

Explanation

Efficiency is the ratio of output to input, often expressed as a percentage.

It represents how much of the input energy is actually converted into useful output energy, with the rest being lost as waste or heat.

Key Points:

• Energy is the ability to do work.
• Work is the transfer of energy through a force applied over a distance.
• Power is the rate at which work is done or energy is transferred.

Explanation

The Earth bulges at the equator and rotates, creating a centrifugal force that slightly reduces gravity there.

At the poles, this effect is minimal, so ‘g’ is stronger at the poles than at the equator.

Explanation

The time period T of a simple pendulum is given by: T = 2π√L/g

It depends on length (L) and acceleration due to gravity (g), but is independent of mass.

Explanation

 When a forward bias is applied to a p-n junction:

The potential barrier decreases.

Electrons from the n-side move toward the p-side.

These electrons are minority carriers on the p-side.

As a result, the concentration of electrons on the p-side increases, but only slightly, since it's still a small number compared to the holes (which are majority carriers on the p-side).

Explanation

• It takes Mercury approximately 88 Earth days (specifically 87.97 days) to complete one orbit around the Sun
• This means that Mercury's year is equal to 88 Earth days
• Distance: Approx. 58 million km from the Sun
• But its rotation takes nearly 59 days. 
• Speed: ~47 km/s

Last updated question 2 May 2026 by NS

Explanation

When an object is dropped from rest (not thrown), its initial velocity is zero.