If you mean 2 bare copper wires those are the ground wires. Tie them together and then connect the light fixture ground wire which will be green or bare copper to those ground wires.
Connect the ground wire to the metal box.
If you are referring to a porcelain or plastic ceiling light fixture most do not have a place to connect the ground wire. You cannot ground these type fixtures. Just connect the ground wire to the mounting crossbar and forget about connecting it to the light itself. It is on the ceiling and will never be touched unless you change the bulb and then you will have the switch in the off position. It is perfectly safe.
If you're asking whether you have to connect the fixture ground to the house ground, you do. The idea is to connect any exposed portion of a metal fixture to ground, keeping anything you would be able to touch from having a hazardous potential on it. The way to do this is to connect the fixture ground (which is connected to the metal chassis) to the building ground (which comes from your electrical panel).
Can lights have a junction box attached to them. So yes.
The green wire on the light fixture is a ground wire. If there is no ground wire in the conduit, the green wire should be attached to the metal box with a screw.
The fixture box should have a ground screw on the bottom of the box. Sometimes you have to move other wires out of the way to see it. Just reconnect the fixture ground wire to this screw.
Yes. Connect Black to Black, White to White and bare ground wires together.
If you mean 2 bare copper wires those are the ground wires. Tie them together and then connect the light fixture ground wire which will be green or bare copper to those ground wires.
Normally the fixtures come with a grounding screw that you attach the grounding wire to. If the box you attaching the fixture to is metal and there is no grounding wire present then the grounded conduit should ground you fixture.
Connect the ground wire to the metal box.
If you are talking about the lamp then the answer is no. If you are talking about the fluorescent fixture, it should be. It is the fixture grounding that helps the tube to ignite. because of the close proximity to the metal of the fixture. There are many occasions when the fixture will not operate, but as soon as the ground is connected the fixture operates fine.
If you don't have the wire then you just can't ground it. This should not be too much of a problem. Most light fixtures are not grounded and some don't even have ground wires.
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A fixture is what the light bulb goes into.
Yes
If you are referring to a porcelain or plastic ceiling light fixture most do not have a place to connect the ground wire. You cannot ground these type fixtures. Just connect the ground wire to the mounting crossbar and forget about connecting it to the light itself. It is on the ceiling and will never be touched unless you change the bulb and then you will have the switch in the off position. It is perfectly safe.