If a lightbulb on a device stops working, is there a way to know if it malfunctioned internally or externally?

Question

If a an AC 120V 25 watt light bulb on a device (such as a lamp) stops working and one of its contact wires separates, is there a way to determine whether the light bulb expired (reached the end of its lifespan) or if it was a power surge which ruined the device that the light bulb was in, thus compromising the light bulb itself? If there are blue and white-colored stripes forming on the top of the light bulb after the light bulb has stopped working, what does that mean?

Answer 1

If you can borrow an electrical test meter, you can do a continuity check of the bulb to see if the bulb should work. There are also electrical testers available from any hardware store that detect the presence of electricity without having to touch wires. The most simple way is the shake the bulb. if you hear clinking, its probably just the bulb.

Even a power drain which is referred to as "line drop" happens, it should not affect the bulb. This is when the lights dim when something turns on in the house like the refrigerator. The stripes you are seeing could just be a chemical reaction within the bulb.

Answer 2

first unplug are turn it off,  remove the light bulb from the socket, there  is a small flat copper flap in side the light socket take the head of a nail and  pull it up a little. if that not it ,replace the socket and wiring R W Jones here.?