Electricity Problem

How much voltage must be used to accelerate a proton (radius 1.2e-15m) so that it has sufficient energy to just penetrate a silicon nucleus? A silicon nucleus has a charge of +14*1.602e-19 and its radius is about 3.6e-15m. Assume that the potential is that for point charges.

Electricity Problem

Two identical +7.5e-6 point charges are intially spaced 5.5cm from each other. If they are realesed at the same instant from rest, how fast will they be moving when they are very far away from each other? Assume they have identical masses of 1.0 mg.

Finding the radius of a concave mirror using the intensity of sunlight.

The intensity of sunlight is 1.00 kW/m^2. A highly reflective concave mirror is pointed at the sun to produce a power of at least 350 W at the image. a) Find the radius r of the circular mirror. b) Suppose the light intensity is to be at least 120 kW/m^2. Find the relationship between r (the radius) and R (the curvature) of the mirror. The disk of the Sun subtends an angle of 0.533 degrees at the Earth.

Two glass plates in contact separated by a thread at one end where is the next dark fringe?

Two glass plates 10cm long are in contact at one end and seperated at the other end by a thread .050 mm in diameter. Light containing two wavelengths 400nm and 600nm is incident perpendicularly. At what distance from the contact point is the next dark fringe? Please show me the method step by step. Answer 1.2mm Thanks

Light through a filter. Find the thickness of the transparent dielectric.

Astronomers observe the chromosphere of the Sun with a filter that passes the red hydrogen spectral line of wavelength 656.3 nm. The filter consists of a transparent dielectric of thickness d held between two partially aluminized glass plates. The filter is held at a constant temperature. a) Find the minimum value of d that produces the maximum transmission of this perpendicular H light (656.3 nm), if the dielectric has an index of refraction of 1.378. b) What happens to the transmitted wavelength if the temperature of the filter is increased but the index of refraction does not change significantly? c) The dielectric will also pass what near-visible wavelength? One of the glass plates ... click for more