Answer
The answer is option A. Because when the balloon air is heated it increases the air volume inside as a result it becomes less dense compare to the cooled air outside. So it rises high.
If balloon air is heated the hot air not only rises inside the balloon but also comes down because the motion of molecules are random in nature. So the option B is wrong.
When the balloon air is heated pressure is increases that is true but it increase in all the direction of the balloon. Because pressure is nothing but momentum imparted by gas on the wall per second. As the molecules in random in nature so it will impart momentum in all directions. Option C is wrong.
Option D is wrong because air can also escape when the balloon air is not heated.
Option E is wrong because the molecules are moving faster and heating the balloon more not only in the upper direction but all the directions due its random in nature. So the resultant force is zero.
Work Step by Step
The answer is option A. Because when the balloon air is heated it increases the air volume inside as a result it becomes less dense compare to the cooled air outside. So it rises high.
If balloon air is heated the hot air not only rises inside the balloon but also comes down because the motion of molecules are random in nature. So the option B is wrong.
When the balloon air is heated pressure is increases that is true but it increase in all the direction of the balloon. Because pressure is nothing but momentum imparted by gas on the wall per second. As the molecules in random in nature so it will impart momentum in all directions. Option C is wrong.
Option D is wrong because air can also escape when the balloon air is not heated.
Option E is wrong because the molecules are moving faster and heating the balloon more not only in the upper direction but all the directions due its random in nature. So the resultant force is zero.
