Reference no: EM132592224

Just about everyone at one time or another has been burned by hot water or steam. This problem compares the heat input to your skin from steam as opposed to hot water at the same temperature.

Assume that water and steam, initially at 100 °C , are cooled down to skin temperature, 34.0 °C , when they come in contact with your skin. Assume that the steam condenses extremely fast. We will further assume a constant specific heat capacity c=4190J/(kg⋅K) for both liquid water and steam.

How much heat H1 is transferred to the skin by 41.0 g of steam onto the skin? The latent heat of vaporization for steam is 2.256×106 J/kg

2.The hot glowing surfaces of stars emit energy in the form of electromagnetic radiation. It is a good approximation to assume that the emissivity e is equal to 1 for these surfaces.

Part A

Find the radius RRigel of the star Rigel (the bright blue star in the constellation Orion) that radiates energy at a rate of 2.70×1032 W and has a surface temperature of 1.10×104 K . Assume that the star is spherical.

Use σ=5.67×10-8W/m2⋅K4 for the Stefan-Boltzmann constant.

Part B

Find the radius RProcyonB of the star Procyon B, which radiates energy at a rate of 2.10×1023 W and has a surface temperature of 1.00×104 K . Assume that the star is spherical.

Use σ=5.67×10-8W/m2⋅K4 for the Stefan-Boltzmann constant.