Radiation | MCQs

Explanation

Sunlight travels at the speed of light.

Sunlight an average of 8 minutes and 20 seconds to travel from the Sun to the Earth.

Light from Sun travels a distance of  150 Million km before it reaches Earth

Moonlight an average of 1.3 seconds to travel from the moon to the Earth.

ND16-3-2023

Explanation

Gamma radiation is the most dangerous type of radiation.

it has high energy and can penetrate most materials, including human tissue.

It is highly penetrating and can cause significant biological damage.

Explanation

• The heat from the Sun reaches Earth in the form of electromagnetic waves, which is called radiation.
• This includes ultraviolet (UV) rays, visible light, and infrared (IR) rays.
• Radiation is the transfer of energy through electromagnetic waves, without the need for a medium like air or water.

Explanation

A thermos flask is designed to reduce heat transfer through all three methods:

• Conduction: The flask has a vacuum insulation, which eliminates conduction through the container.
• Convection: The flask's design and vacuum insulation prevent convective heat transfer.
• Radiation: The flask's reflective coating minimizes radiant heat transfer.

Explanation

Blast, thermal radiation, and prompt ionizing radiation cause significant destruction within seconds or minutes of a nuclear detonation.

The delayed effects, such as radioactive fallout and other environmental effects, inflict damage over an extended period ranging from hours to years

Explanation

Gamma (γ) radiation consists of high-energy electromagnetic waves, such as X-rays or gamma rays, that travel in a straight line and are not affected by electric or magnetic fields.

Gamma radiation is a form of ionizing radiation and can travel several meters in air or several centimeters in dense materials before being absorbed.

Explanation

Alpha (α) radiation consists of heavy, positively charged particles (alpha particles) that are emitted from the nucleus of an atom during certain types of radioactive decay.

Alpha particles are highly ionizing, meaning they can efficiently remove tightly bound electrons from atoms, resulting in the formation of ions.

Explanation

• Gamma rays are commonly used for sterilization of medical instruments.
• Because of their high energy and penetrating power, which allows them to effectively kill bacteria and other microorganisms.
• Gamma radiation is also used to sterilize medical supplies.
• Such as syringes, gloves, and implantable devices.

Explanation

• Neutrons are the most penetrating, because they have no charge and a relatively large mass compared to electrons and protons.
• This allows them to travel long distances through matter without being deflected or absorbed, making them highly penetrating.

Explanation

The cooling fins at the back of a refrigerator are typically made of a black, rough surface to maximize heat radiation. This design:

• Increases the surface area for heat transfer
• Absorbs heat from the surrounding air
• Emits heat more efficiently due to the rough surface