Question

Statement 1: At constant pressure, the volume of a fixed amount of any gas is inversely proportional to its absolute temperature.
Statement 2: The hot air balloon is based on the application of Charles’ law.

• A. Both statement 1 and 2 are false.
• B. Statement 2 is true but 1 is false.
• C. Both statement 1 and 2 are true.
• D. Statement 1 is true but 2 is false.

Answer 1

The correct option is B Statement 2 is true but 1 is false.

Statement 1:

• Charles' law: At constant pressure, the volume of any gas is directly proportional to its absolute temperature . So, the statement 1 is false.

Statement 2:

• The hot air balloon works based on the application of Charles' law.
• V∝T , according to Charles’ law.
• A hot air balloon consists of a big balloon, a basket to carry passengers and a fuel source. On ignition of the fuel, the air inside the balloon heats up.
• According to Charles’ law, the volume of gas increases with increase in the temperature of gas. So, the density of the air inside the balloon decreases. This helps the balloon to float upwards.
• Hence, the statement 2 is true.