Which statement is true regarding lift as developed by a hot air balloon?

The statement that the lift generated by a hot air balloon is greater with an increased temperature difference between the ambient air and the air inside the envelope is fundamentally rooted in the principles of buoyancy. According to Archimedes’ principle, lift occurs because the air inside the balloon is heated, making it less dense than the cooler air outside. This temperature difference leads to a greater buoyant force acting on the balloon, as the volume of the heated air expands while its weight remains constant.

When the temperature of the air inside the envelope is significantly greater than that of the surrounding atmosphere, the balloon becomes more buoyant due to the increased density difference. Therefore, the greater the temperature differential, the more lift is produced, allowing the balloon to rise higher. This relationship showcases the importance of temperature in controlling the balloon's performance, establishing why this statement is true.

In contrast, the other statements do not accurately reflect the principles of hot air balloon physics. For instance, lift is indeed affected by temperature variations (contrary to the claim that it remains constant), it relies on the weight of the balloon (which encompasses the envelope and the payload), and while size plays a role in potentially increasing the lift by providing more volume for heated air, it is not