A rectangular loop of wire carrying a 4.0-A current is placed in ...

[Wadzanai]

A rectangular loop of wire carrying a 4.0-A current is placed in a magnetic field of 0.60 T. The magnitude of the torque acting on this wire when the plane of the loop makes a 30 angle with the field is measured to be 1.1 N  m.
 
  What is the area of this loop? A) 0.20 m2
  B) 0.40 m2
  C) 0.26 m2
  D) 0.80 m2
  E) 0.53 m2

Question 2

The focal length of the lens of a simple film camera is 40.0 mm.
 
  By what amount should the distance between the lens and the film be increased or decreased to change the focus from a person who is 25 m from the lens to one who is 4.0 m from the lens?
  A) 0.2 mm
  B) 0.3 mm
  C) 0.4 mm
  D) 0.5 mm
  E) 0.7 mm

[vickyvicksss]

Answer to Question 1

E

Answer to Question 2

B

[Wadzanai]

Gracias!

[nguyenhoanhat]

Excellent