Metal detectors that locate metal beneath sand on a beach are ...

[Engineer]

Metal detectors that locate metal beneath sand on a beach are activated by
 
  A) electric fields.
  B) magnetic fields.
  C) electromagnetic induction.
  D) alternating current.

Question 2

When a bar magnet is thrust at the same speed into a coil having twice the number of loops, the induced voltage is
 
  A) half.
  B) the same, no different.
  C) twice as much.
  D) four times as much.
  E) none of the above

[xiaomengxian]

Answer to Question 1

Answer: C

Answer to Question 2

Answer: C

[Engineer]

Thanks for the timely response, appreciate it

[sailorcrescent]

Wow, this really help