How much kinetic energy does a 2 kg book falling out of the backpack with a velocity of 4 m/s have?

What are chlorofluorocarbons and what impact do they have on the atmosphere?

Starting with only the balmer series light (visible light), how could we ensure that the solar panels generate a current that mark can use for his power station? a)by gradually increasing the brightness (amount) of light that we shine on it. b)by gradually increasing the frequency of the light we shine on it. c)by gradually increasing the wavelength of the light that we shine on it.

What is a possible result of higher air temperature caused by global warming