Which is lighter warm air or cold air?
Also question is, which air is lighter warm or cold?
Cold air is denser than warm air. The molecules are packed closer together. The amount of water vapor in the air also affects the density of the air. The more water vapor that is in the air, the less dense the air becomes.
Keeping this in view, how will you show that warm air is lighter?
Tie a thread in the centre of the stick and hold the stick by the thread to balance it. Place a burning candle below one of the bags. The bag above the candle goes up, as the air above the candle becomes warm, it rises, and pushes the bag up.
Warmer air is less dense than cold, which is why warm air tends to rise and cold air sinks. Being acted on by gravity, colder, denser air weighs more and exerts greater pressure per unit area. At sea level, air, on average weighs about 14.7 pounds square inch.