The pressure cooker is heated at the base to cook the food. The pressure cooker releases steam when the force exerted by pressure exceeds the counterweight, at which point the weight rises up allowing steam to escape. The time to cook is measured by the number of times steam is released.

When food(dry lentils) is kept in a container inside the pressure cooker it does not cook as well as if it were dumped in there directly. The same amount of water is added to the food in both cases, though in the former case there is also some water in the base of the cooker outside the container. In both cases the cooker was allowed to release steam 3 times.

I thought that based on Pascal's law the same pressure would be exerted on the water in the container as it would if kept there directly. Since the temperature is the same, in both cases the food should be completely cooked. However practical results differ. Please suggest a theory which explains this.

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    $\begingroup$ Was the time required the same in both cases? Maybe the cooker released pressure thrice in a shorter time in the second case? $\endgroup$ – Pranav Hosangadi Oct 26 '13 at 17:05
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    $\begingroup$ In that case I would expect it to cook even better as it spends more time being cooked $\endgroup$ – Bug Killer Oct 26 '13 at 17:56
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    $\begingroup$ Sorry, by second case I meant the "food in container" case $\endgroup$ – Pranav Hosangadi Oct 27 '13 at 16:06
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    $\begingroup$ Tried it out. Both took about the same time $\endgroup$ – Bug Killer Oct 30 '13 at 4:23
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    $\begingroup$ Here's a thought - cooking does not depend on temperature, it depends on the amount of heat pumped into the food. Can you think of any reason that the heat would enter the food quicker if it was directly inside the cooker, instead of inside another vessel? $\endgroup$ – Pranav Hosangadi Oct 30 '13 at 4:45

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