A ball is thrown vertically upwards at an initial speed of 23
m s
−
1
. What is the displacement of the ball 3 seconds after it was thrown?

If steel is more dense that lake water, why can a boat float

What are similarities and differences of reflection, refraction, diffraction and absorption?

An ice-making machine inside a refrigerator operates in a carnot cycle. it takes heat from liquid water at 0.0 degrees celsius and rejects heat to a room at a temperature of 19.2 degrees celsius. suppose that liquid water with a mass of 76.3kg at 0.0 degrees celsius is converted to ice at the same temperature. take the heat of fusion for water to be l_f = 3.34*10^5 j/kg.how much energy e must be supplied to the device? express your answer in joules.