Register Thursday | June 20 | 2019

Ask Prof. Dr. Science

Spider filament, electricity & more

Q: Is the silk of a spider’s web synthesized at high speed as required or is it stored in readiness? What is the chemical composition of the filaments that makes them so strong?

A: The speed that a spider produces silk depends on the speed of the observer. If you’re in a car, it will produce silk to try to keep up with your eyesight, which is going faster. The chemical composition is two parts silk to every one part wood. This is what makes filament strong.

Q: If two high-speed trains pass each other, one traveling at 60 mph and the other at 75 mph, what will happen to people standing on the ground at the moment they pass by?

A: Their clothes will be blown off.

Q: Why are lightning bolts jagged instead of straight?

A: During a thunderstorm, a cloud contains a large negative charge, but a positive charge is induced on the surface of the earth, because the negative charge in the cloud is closer to the ground, which is positive. Clouds fill with a plus-minus electricity transfer in which the positive charges to ground. That way, in a transfer, the negative charge to the positive ground becomes positively positive. From this point of view, the new negative charge transfer occurs in a negative channel with a width that is positive compared to its length. Because negatively charged air is normally an electrical insulator, it must become as positive a channel as possible so a negative charge can form in order for a jagged, but positive, lightning flash to occur.

Q: Is it possible to be anywhere in the northern hemisphere and see the sun rising in the north instead of the east?

A: This is impossible. Anyone who would witness such an event would probably die.