A small dust particle of mass 7.90 10-6 g is being observed ...

[codyclark]

A small dust particle of mass 7.90  10-6 g is being observed under a magnifying lens.
 
  Its position is determined to within 0.0050 mm. (1 y = 3.156  107, h = 1.055  10-34 J  s)
  (a) Find the minimum uncertainty in its velocity implied by the uncertainty in its position.
  (b) Assuming the dust particle is moving at the speed you just found, how many years would it take for the particle to move 1.0 mm?

Question 2

A galvanometer with a coil resistance of 80  deflects full-scale for a current of 2.0 mA. What series resistance is required to convert it to a voltmeter reading full scale for 200 V.
 
  A) 100 m B) 13 M C) 250 k D) 0.80 m E) 100 k

[akudia]

Answer to Question 1

(a) 2.7  10-21 m/s (b) 1.2  1010 y

Answer to Question 2

E

[codyclark]

Great answer, keep it coming

[nguyenhoanhat]

Gracias!