The number density of conduction electrons in a metal can be found from the density ? of the metal, the mass per mole M of the metal, the number of conduction electrons per metal atom, and Avogadro's number NA. If we assume one conduction electron per atom, which of the following gives the number density of conduction electrons for a given metal?
a. NA ?M
b. NA ? /M
c. NA M /?
d. NA /?M
b
You might also like to view...
A tractor T is pulling two trailers, 
and 
with a constant acceleration. T has a mass of 200 kg, 
has a mass of 100 kg, and 
has a mass of 150 kg. If the forward acceleration is 0.60 
then the horizontal force on the tractor due to the ground is
A. 270 N backward.
B. 270 N forward.
C. 150 N backward.
D. 150 N forward.
E. 90 N forward.
An aquarium contains a 5-cm layer of water (n = 1.333) floating on top of carbon tetrachloride (n = 1.461). If the angle of incidence into the water from the carbon tetrachloride is 20°, what is the angle of refraction into the air?
A. 20° B. 30° C. 38° D. 69° E. 26°
A banked curve in a roadway is designed for a speed of 35 mph. During an ice storm cars should be able to safely negotiate this curve at 35 mph, because at this speed
A. the necessary centripetal force is supplied entirely by the normal force from the road. B. (and at all speeds) the acceleration vector of the car points down, helping maintain stability. C. the necessary centripetal force is supplied entirely by gravity. D. the centrifugal force of the car exactly balances the centripetal force.
100 grams of molten lead (600°C) is used to make musket balls. If the lead shot is allowed to cool to room temperature (21°C), what is the change in entropy (in J/K) of the lead? (For the specific heat of molten and solid lead use 1.29 J/g/°C; the latent heat of fusion and the melting point of lead are 2.45 × 10^4 J/kg and 327°C.)
a. ?145 b. ?252 c. ?302 d. ?429 e. ?100