Which element was detected in the Sun before it was found on ...

[Mr. Wonderful]

Which element was detected in the Sun before it was found on Earth?
 a. Hydrogen
  b. Promethium
  c. Helium
  d. Argon

Question 2

A square loop (length along one side = 20 cm) rotates in a constant magnetic field which has a magnitude of 2.0 T. At an instant when the angle between the field and the normal to the plane of the loop is equal to 20 and increasing at the rate of 10/s, what is the magnitude of the induced emf in the loop?
 a. 13 mV
  b. 0.27 V
  c. 4.8 mV
  d. 14 mV
  e. 2.2 mV

[zhanghao]

Answer to Question 1

c

Answer to Question 2

c

[Mr. Wonderful]

Wow, this really help

[Sarahjh]

Gracias!