Estimate the effective temperature of the sun from the fact that the human eye is sensitive to light in the range 400-700 nm (1nm = 10^-9m). hint: use wien's law.
the book used is "astrophysics in a nutshell" by dan maoz

Which is the most accurate name for the ionic compound cas?

Ahorizontal force of 400.0 n is required to pull a 1760 n truck across the floor at a constant speed. find the coefficient of sliding friction.

Two kilograms of air within a piston–cylinder assembly executes a carnot power cycle with maximum and minimum temperatures of 800 k and 300 k, respectively. the heat transfer to the air during the isothermal expansion is 60 kj. at the end of the isothermal expansion the volume is 0.4 m3. assume the ideal gas model for the air. determine the thermal efficiency, the volume at the beginning of the isothermal expansion, in m3, and the work during the adiabatic expansion, in kj.