Calculate the rate of loss of heat through a glass window of area 1000 cm 2 and thickness 0.4 cm when temperature inside is 370 and outside is -50. (K glass .=2.2 × 10-3 cals -1 cm -1 K -1)

Question

Calculate the rate of loss of heat through a glass window of area 1000 cm 2 and thickness 0.4 cm when temperature inside is 370 and outside is -50. (K glass .=2.2 × 10-3 cals -1 cm -1 K -1) (A) 450 cal/s (B) 231 cal/s (C) 439 cal/s (D) 650 cal/s

Tardigrade Admin · Accepted Answer

(Q/t)=(K A Δ θ/L) =(2.2 × 10-3 × 103 × 42/4 × 10-1) =231 cal / s

Q. Calculate the rate of loss of heat through a glass window of area $1000 c m^{2}$ and thickness $0.4 c m$ when temperature inside is $3 7^{0}$ and outside is $- 5^{0}$ . (K glass $= 2.2 \times 1 0^{- 3} c a l s^{- 1} c m^{- 1} K^{- 1})$

450 cal/s

231 cal/s

439 cal/s

650 cal/s

$\frac{Q}{t} = \frac{K A Δ θ}{L}$
$= \frac{2.2 \times 1 0 ^{- 3} \times 1 0 ^{3} \times 42}{4 \times 1 0 ^{- 1}}$
$= 231 c a l / s$

Q. Calculate the rate of loss of heat through a glass window of area 1000cm2 and thickness 0.4cm when temperature inside is 370 and outside is −50. (K glass =2.2×10−3cals−1cm−1K−1)