Explanation

Silicon is a semiconductor material crucial for converting sunlight into electricity in solar cells.

It is widely used due to its abundance and efficient photovoltaic properties.

Explanation

Given kinetic energy (K.E) = 1 J and mass (m) = 1 kg:

K.E = ½mv²

1 = ½ * 1 * v²

v² = 2

v = √2 ≈ 1.414

The correct answer is 1.4 m s⁻¹.

Explanation

The human hearing range is typically from 20 Hz to 20,000 Hz.

Sounds below 20 Hz are called infrasound.

Sounds above 20,000 Hz are called ultrasound, both of which are inaudible to humans.

Since 22,000 Hz is above 20,000 Hz, it is an inaudible sound.

Explanation

Ohm’s Law states that V = IR, where voltage (V) is directly proportional to current (I) and resistance (R).

It is the fundamental principle describing the relationship between voltage, current, and resistance in electrical circuits.

Explanation

Explanation

A nebula is a giant cloud of dust and gas in space.

Some nebulae come from the gas and dust thrown out by the explosion of a dying star, such as a supernova.

Explanation

Systolic pressure, the top number in a blood pressure reading, represents the pressure in arteries when the heart beats.

A normal value is approximately 120 Torr (mmHg).

Explanation

The escape velocity of a body in the gravitational field of Earth is primarily dependent on the mass of the Earth and the radius of the Earth.

It does not depend on the mass of the body or the angle at which it is thrown.

The formula for escape velocity 𝑣e is given by:

Explanation

False ceilings help in improving insulation, cooling, and acoustics, while also providing a clean space to hide wires and pipes.

Explanation

As an object approaches the speed of light, the object's mass becomes infinite and so does the energy required to move it.

That means it is impossible for any matter to go faster than light travels.