Explanation

In the dark, a Light Dependent Resistor (LDR) has a high resistance.

Explanation

• In atomic physics, the energy of an electron in an atom is quantized, meaning it can only take on specific discrete values.
• This is a fundamental principle of quantum mechanics, which states that energy is not continuous, but rather comes in small, discrete packets (quanta).
• The energy levels of electrons in an atom are determined by the solutions to the Schrödinger equation, and they are characterized by specific energy values, known as energy eigenvalues.
• These energy levels are quantized, meaning they can only take on specific values, and not any arbitrary value.

Explanation

• Radioactivity was discovered by Henri Becquerel, a French physicist, in 1896.
• He discovered this when he was studying uranium and noticed that it emitted radiation without an external source of energy.
  
• The term radioactivity was coined by Marie Curie, who, along with her husband, investigated this phenomenon.
• Rutherford, a British physicist, studied the properties of radioactive decay and named the particles alpha, beta and gamma.

Explanation

• Nights are cooler in the deserts than in the plains because Sand radiates heat more quickly than the earth.
• Because deserts have such little water vapor in the air, it makes it harder to trap heat or cold in a desert.
• At night, the sun no longer heats the desert and the heat from the day doesn't stay trapped.
• Because of this, some deserts can get cold at night, dropping to below 40F, which is definitely coat weather.

Explanation

• Gravitational potential is always negative, because it is defined as the work done per unit mass to bring an object from infinity to a given point in a gravitational field.
• Since the force of gravity is attractive, work must be done to move an object against the force of gravity, and this work is negative.

Explanation

• Velocity is the speed of a body in a specific direction.
• It is a vector quantity, which means it has both magnitude (amount of movement) and direction.

Explanation

A component that obeys Ohm's law is called an "Ohmic component."

Explanation

Explanation

• The electric field strength related to Hall voltage is given by VH/d, where V is the Hall voltage and d is the width of the conductor.
• The Hall effect is the production of a potential difference (the Hall voltage) across an electrical conductor that is transverse to an electric current in the conductor and to an applied magnetic field perpendicular to the current.

Explanation

The force exerted by the atmosphere on the surface of the water is equal to the pressure multiplied by the area of the surface:

Force = Pressure x Area

= 100 kPa x (2 m x 1 m)

= 100,000 Pa x 2 m^2

= 200,000 N

= 200 kN