Asolar heated house loses about 5.4 × 107 cal through its outer surfaces on a typical 24-h winter day.

what mass of storage rock is needed to provide this amount of heat if it is brought up to initial temperature of 62°c by the solar collectors and the house is maintained at 20°c? (specific heat of rock is 0.21 cal/g⋅°c.)

a. 163 kg
b. 1 230 kg
c. 6 100 kg
d. 12 700 kg

C

Explanation:

Q=mcΔθ

Q=quantity of heat   , m= mass of the storage rock

Δθ= temperature change.

m= Q/(cΔθ)

Q=5.4

Δθ=62°C-20°C

 =42°C

c=0.21cal/g.°C

m≈6100000g

m≈6100kg

answer: the correct answer id option(d).

explanation:

snell's law refraction:

the angle of refraction =

the angle of incidence =

refractive index of air = = 1

refractive index of glycerol = 1.47

from the given options, the most closest answer to 63.72° is 65° of option (d).