Why do transformers hum? Transformer noise is caused by a phenomenon which causes a piece of magnetic sheet steel to extend itself when magnetized. When the magnetization is taken away, it goes back to its original condition. This phenomenon is scientifically referred to as magnetostriction.
Answer:
a) Beth will reach before Alan
b)Beth has to wait 20 min for Alan to arrive
Explanation:
let 'd' be distance b/w Los Angeles and San Francisco i.e 400 mi
considering ,
Alan's speed
=50mph
Beth's speed
=60mph
->For Alan:
The time required
= d/
= 400/50 => 8h
-> For beth:
The time required
=> 6h 40m
Alan will reach at 8:00 a.m +8h = 4:00p.m.
Beth will reach at 9:00 a.m +6h 40m= 3:40p.m.
a) Beth will reach before Alan
b)Beth has to wait 20 min for Alan to arrive
Air sample of places around the world compared to clean air
The correct answer is B. wrap more coils of wire around the nail. This is how you can increase its magnetic strength. Thank you for posting your question. I hope this answer helped you. Let me know if you need more help.