The coefficients of absorption and reflection of the surface of a body are 0.70 and 0.25 respectively. If 200 calories of radiant heat is incident on the surface of the body, the quantity of heat transmitted will be

The coefficients of absorption and reflection of the surface of a body

1.	The coefficients of absorption and reflection of the surface of a body are 0.70 and 0.25 respectively. If 200 calories of radiant heat is incident on the surface of the body, the quantity of heat transmitted will be
Answer» 140 cal 50 cal 10 cal 60 cal Solution :`a+r+t=1` `t=1-(a+r)=1-0.95=0.05` `Q_(t)=1t+Q=0.05xx200=10cal`

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The coefficients of absorption and reflection of the surface of a body are 0.70 and 0.25 respectively. If 200 calories of radiant heat is incident on the surface of the body, the quantity of heat transmitted will be

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