A roller coaster has a mass of 300 kg. It drops from rest at the top of a hill that's 101 m tall. How fast is it going when it reaches the bottom?
Acceleration due to gravity is g = 9.8 m/s2.

Alinearly polarized electromagnetic wave has an average intensity of 196 w/m^2. this wave is directed towards two ideal polarizers (in real polarizers, transmission is also effected by reflection and absorption). polarizer a is oriented with its transmission axis at an angle of θ_1=20.8∘ with the incident electric field. polarizer b has its axis at an angle of θ_2=63.0∘ with the incident electric field. what is the average intensity of the wave after it passes through polarizer a? what is the average intensity of the wave after it passes through polarizer b? suppose that the two polarizers a and b are interchanged. what would the average intensity be after passing through both polarizers?

Ascientist wants to test ways to reduce pollution in lake . what is the bestway of doing this

All phase changes are .an example of a phase change is an ice cube melting