A cubic metal block of mass 5 ,kg and edge length 0.1 ,m and at an initial temperature of 100^{circ}

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10-2.Transmission of Heat

hard

A cubic metal block of mass $5 \,kg$ and edge length $0.1 \,m$ and at an initial temperature of $100^{\circ} C$ is placed on a thermally insulating flat surface and exposed to air at $0^{\circ} C$. The time in seconds required to cool the block to a temperature of $37^{\circ} C$ is closest to

(Note: Specific heat of the metal $=500 \,J / kg /{ }^{\circ} C$; Heat transfer coefficient from block to air $=50 \,W / m ^2 /{ }^{\circ} C$ )

A

$500$

B

$1000$

C

$1500$

D

$2000$

(KVPY-2021)

Solution

(B)

Standard 11

Physics

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