Three solid objects of the same material and of equal mass

Three solid objects of the same material and of equal mass –
a sphere, a cylinder (length = diameter) and a cube – are at
5000C initially. These are dropped in a quenching bath
containing a large volume of cooling oil each attaining the
bath temperature eventually. The time required for 90%
change of temperature is smallest for

a) cube
b) cylinder

c) sphere
d) equal for all the three
whyyyyyyy???????

Question Posted / chitta447

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Three solid objects of the same material and of equal mass – a sphere, a cylinder (length = diame..

Answer / debshree

ANSWER 1 IS CORRECT

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4 Yes

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Three solid objects of the same material and of equal mass – a sphere, a cylinder (length = diame..

Answer / vinay upadhyay

answer (d) is correct . because here change of tempr is depend on characteristic length of object and according to ques characteristic length of each will same so their gainig of 90% of tempr difference will requires same time . tou =row *characteristic length*heat capacity /heat transfer cofficient

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Three solid objects of the same material and of equal mass – a sphere, a cylinder (length = diame..

Answer / vas

answer 1 (cube) is correct since temp change depends on few
factors, one of which is footage (S) of contact between the
body and substance. Among other equal factors the footage
is different. Thus, the only problem for us here is to find
out solution how to compare footages of the bodies we have.
Since we know that their weights are equal and know the
formulas for figuring out their weights, we will find soon
that the smallest S belongs to the cube, consequently the
biggest belongs to the sphere.

Is This Answer Correct ?

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2 No

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