Answer:
A blackbody, or Planckian radiator, is a cavity within a heated material from which heat cannot escape. No matter what the material, the walls of the cavity exhibit a characteristic spectral emission, which is a function of its temperature.
Example:
Emission from a blackbody is temperature dependent and at high temperature, a blackbody will emit a spectrum of photon energies that span the visible range, and therefore it will appear white. The Sun is an example of a high-temperature blackbody.
Concaved lenses...........
Answer:
Explanation:
given,
diameter of merry - go - round = 2.40 m
moment of inertia = I = 356 kg∙m²
speed of the merry- go-round = 1.80 rad/s
mass of child = 25 kg
initial angular momentum of the system
final angular momentum of the system
from conservation of angular momentum