Newtons Law Of Gravitation

The threshold wavelength corresponds to the minimum wavelength of light that can cause the emission of electrons from a metal surface (photoelectric effect). Radiation with a wavelength shorter than the threshold wavelength has sufficient energy to knock electrons off the surface. - Blue, Indigo, Violet, and UV all have shorter wavelengths than green light, so they can cause the emission of electrons. - Orange light has a longer wavelength than green light, so it does not have enough energy to cause electron emission. Thus, Orange light cannot cause emission of electrons.

Concept: Pressure increases with depth, gravity decreases.

Step 1: Air pressure.
Deeper → more overlying air → higher pressure.

Step 2: Gravity.
Inside Earth:

Concept: Gravitational field:

Step 1: Let point be at distance from mass .
Distance from =

Step 2: Equate fields.


Step 3: Solve.