How much heat is absorbed by 20g granite boulder as enegry from the sun causes its temperature to change from 10 celsius to 29 celsius?

m = mass of granite boulder = 20 g

c = specific heat of granite boulder = 0.79 J/gC

T₀ = initial temperature of granite boulder = 10 °C

T = final temperature of granite boulder = 29 °C

Q = heat gained by granite boulder as energy from the sun

heat gained by granite boulder is given as

Q = m c (T - T₀)

inserting the values

Q = (20) (0.79) (29 - 10)

Q = 300.2 J

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.