PV Gap

Gordon Said:

Do you think there's going to be a Solar Storm in 2011?

We Answered:

I don't "think" there's going to be a solar storm, I know there is- that's science, it's not opinion.

Julie Said:

solar energy: can a photon be reflected back and forth between the same electrons to create non stop energy?

We Answered:

Sorry, no.

All electromagnetic reflections are governed by the same physical laws as reflections of visible light.

All electromagnetic radiation "carries" energy. When electromagnetic energy is absorbed by any substance the absorbed radiation delivers its energy in discrete indivisible bundles called quanta (Also called photons , even when they refer to non-optical radiation).
The amount of energy E contained in each quantum bundle is uniquely characterized by the frequency f of the electromagnetic radiation.

The amount of energy contained in a single quantum of electromagnetic radiation is given by the famous equation


E= hf
h is a called Planck's constant and equals 6.626 x 10-34 J · s
When one is working in the world of physics on an atomic scale, energies are often expressed in eV (electron volts) rather than in joules.
For purposes of comparison, 1 eV = 1.6022 x 10 -19 J

The energy emitted per photon by a source of electromagnetic radiation depends only upon the wavelength (or alternatively the frequency) of the radiation, not on the brightness of the source.

The total amount of energy absorbed (or emitted) per unit area depends on the product of the intensity (number of photons emitted or absorbed per second) and the energy per photon.

An important consequence of this is that on the atomic and molecular scale, absorption of photons below the threshold energy is impossible, regardless of the intensity of the radiation!

Dr. H

Lena Said:

help with science project?

We Answered:

Easy

u know those cotton balls right?

well....... buy blue ones and red ones

-for the protons use blue cotton balls

- for the neutrons use red cotton balls

and at your school explain what the blue cotton balls are and what the red cotton balls are

Ron Said:

how do solar pond lights recharge their energy?

We Answered:

The solar cells and all the rest of the circuit are inside the sphere where they cannot be seen although diffused light can get in and out.

Bernard Said:

How satellites get high resolution images [0.50 to 2.0m] from space, 600-900 km away from the earth?

We Answered:

actually the distance isn't a real problem once you understand the principles of optics. The focus distance is set to the desired value, meaning the picture is only sharp at that distance. it's like focusing a camera (with a long objective). Practical appliance of this can also be seen when using manual focus on a camera.