The index of refraction of a substance is 1.5. find the sine of the angle of refraction if the sine of the angle of incidence is 0.15.
sin r =

For this, we use the Snells Law to determine the angle of refraction of the substance. It  is a formula used to describe the relationship between the angles of incidence and refraction. We do as follows:

n1sinФ1 = n2sinФ2
1.5(0.15) = sinФ2
sinФ2 = 10 degrees

How many calories in food

stands for electromotive force and it is measured in volts. despite its name, it is not actually the force in the sense of being a "pushing" or "pulling" (not measured in newtons).an equation that relates emf,  ℰ,  to a battery's terminal voltage, v, current, i, and internal resistance, r, is    ℰ = v + irin this case, the emf can be interpreted as a voltage—a difference in electric potential.i would not say that it would be considered an energy. if emf can be defined as the energy/work per a unit charge from a battery or other electric source, then it is not strictly energy.