Rice takes longer to cook in an open pot at a hill station like Leh than in Chennai because, at a high altitude,

air pressure is higher, so water boils above 100 °CCorrect answerYour answerthe flame gives less heat because of the coldCorrect answerYour answerwater there contains more dissolved saltsCorrect answerYour answerair pressure is lower, so water boils below 100 °CCorrect answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer D

Correct answer: D

The boiling point of water falls as the air pressure on it falls.
At high altitude water boils at, say, 88 °C, so the food cooks at a lower temperature and takes longer. A pressure cooker fixes this by raising the pressure.

Worth noting

Dissolved salts actually raise the boiling point slightly, which would speed cooking, not slow it.

Concept: Boiling point and pressure
Typical timeTypical: 60 s
Your timeYours: —

The rule this testsHeat and temperature

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Rice takes longer to cook in an open pot at a hill station like Leh than in Chennai because, at a high altitude,

Explanation