Some furnace filters that you buy for your home are called electro-static. How do they work? Are they worth the extra money?

How much voltage does it take to make electricity jump a one inch gap in air? How much voltage difference is lightning then?

If you have a 60W and a 40W light bulb which bulb has a higher resistance?

Birds perch high on power lines and are not harmed. How can this be?

Is the purpose of lightning rods to attract lightning?