. What creates electricity indirectly from sunlight?

photosynthetic cells producing plant energy
geothermal radiation and heated water
parabolic reflectors heating fluid
photovoltaic cells connected to a grid

If a substance is in the gas phase, which of qualities of the gas will stay constant? a: volume b: mass c: shape d: position of particles

Aphoton is absorbed by an electron that is in the n = 3 state of a hydrogen atom, causing the hydrogen atom to become ionized. very far away from the nucleus, the released electron has a velocity of 750,000 m/s. what was the wavelength of the absorbed photon?

If a negatively charged particle is placed at rest in an electric potential field that increases in the positive x-direction, what will the particle do? a. accelerate in the positive x-direction b. remain at rest c. accelerate in the negative x-direction