PHYSICS 231
Final Examination, December 14, 1995, 9:00am-12:00pm
Instructor: P. Q. Hung
10 points for each problem. READ the problems carefully. SHOW YOUR WORK. DO NOT JUST write the answers down.
Useful formulas (not necessarily applied to all problems below):
; 
;
; 
;
; 
; 
, F= -kx
;
; 
;
; 
kJ/kg.K; C=mc
PV = n RT; R=0.082 L.atm/mol.K; 
;
; 
Ideal Monoatomic Gas.
kJ/kg for water; 1 Pa = 1 N/ 
;
1 atm = 101.3 kPa.
, 
1) What is the angular momentum about the origin of a particle of mass
100 g at position 
m, moving
with a velocity of 
m/s?
2) A weight lifter can lift 115 kg on the earth ( 
km,
kg). What mass could the same weight lifter lift on
(a) the moon ( 
km, 
kg)
(b) the sun ( 
km, 
kg)?
Also, 
3) A room is 6 m by 5 m by 3 m. (a) If the air pressure in the room is 1 atm and the temperature is 300 K, find the number of moles of air in the room. (b) If the temperature rises by 5 K and the pressure remains constant, how many moles of air leave the room?
a) 
moles
b) P,V,R const. 
moles
3650-3590=60 moles leave the room.