Physics Questions

The capacity of a water heater is measured in Gallons or Liters. In the USA, it is measured in Gallons and in India, we measure it in Liters.

Hence, if the capacity of the water heater is 15 gallons or 15 liters, then it says that it can hold 15 gallons or 15 liters of water.

450 mm Hg denotes the air pressure.

Silver is the best conductor of both heat and electricity among metals with a thermal conduction value of about 430 W/(mK).

Gold and copper both come respectably close to silver.

Copper being significantly less costly it is often chosen over silver in many applications.

The amount of water vapor ranges from a trace amount up to 4% of the mass of air. Water vapor exists as an invisible gas in the air.

The amount of water vapor in the air is called absolute humidity. The amount of water vapor in the air as compared with the amount of water that the air could hold is called relative humidity.

The maximum amount of water vapor that can be in the air depends on the air temperature.

Wind and solar energy are examples of Renewable energies. 

Renewable energy sources are those which can be naturally replenished. 

Metamorphism is the method of changing the structure of a rock by using heat and temperature.

Hence, for this to happen the parent rock must be in solid form only. Therefore, option C) is true.

From the given circuit,

The resistors R1 and R2 are in parallel connection and R3 is in series with R1 & R2

The equivalent resistance of R1 and R2 is

Req = (12 × 4)/(12 + 4) = 3 Ω.

Adding R3 in series with the pair gives

R = Req + 9

R = 3 + 9

R = 12 Ω.