Three solid objects of the same material and of equal mass-a sphere, a cylinder (length = diameter) and a cube are at 500°C 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 in temperature is the smallest for (A) Cube (B) Cylinder (C) Sphere (D) Equal for all the three

Three solid objects of the same material and of equal mass-a sphere, a

cylinder (length = diameter) and a cube are at 500°C 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 in temperature is the smallest for

(A) Cube

(B) Cylinder

(C) Sphere

(D) Equal for all the three

by

1 Answer

Answer :

(A) Cube

by

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