Robin wanted to shove a rubber pipe up a plastic tap. The problem is that the pipe's diameter is smaller than that required to secure a tight fit. So, Robin switched on a hair dryer and pointed it towards the pipe. He found that now the pipe fitted in easily. Why is this so?
Correct answer: A. The pipe expanded due to the hot air, and then contracted back again
- A. The pipe expanded due to the hot air, and then contracted back again
- B. The tap got deformed because of the hot air
- C. The hot air caused adhesion between the rubber and plastic
- D. None of the above options are correct
Explanation
Applying heat from the hair dryer caused the rubber pipe to expand due to the increase in temperature. As the material heated up, its molecules gained energy and moved more vigorously, leading to the expansion of the rubber pipe. This made it more pliable, allowing Robin to easily fit it onto the plastic tap, despite the initial size difference. The plastic tube expanded because of heat and then when one stopped applying heat, it contracted by cooling. As substances expand on heating and contract when cooled, the pipe fitted in easily.
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