The black board appears black because:
A. Black is absorbed by the board
B. The color black is reflected back to you by the board
C. All visible light wavelengths (ROYGBV) are absorbed by the board
D. All visible light wavelengths (ROYGBV) are reflected off the board

The speed of light in a material is 0.50 c. what is the critical angle of a light ray at the interface between the material and a vacuum?

Which best describes how fluids change as they travel through different portions of the convection currents? they change to solids at the outer portion of the convection currents. they change to solids at the inner portion of the convection currents. they become more dense at the outer portion of the convection currents. they become more dense at the inner portion of the convection currents

An object with initial temperature 130 ∘ f is submerged in large tank of water whose temperature is 50 ∘ f . find a formula for f ( t ) , the temperature of the object after t minutes, if the cooling constant is k = − 0.2 . remember newton's law of cooling (the rate of change of temperature with respect to time is equal to k times the difference between the temperature of the object and the surrounding temperature) ! : )