A certain amount of ideal monatomic gas is maintained at constant ...

[NguyenJ]

A certain amount of ideal monatomic gas is maintained at constant volume as it is cooled from 455K to 405 K. This feat is accomplished by removing 400 J of heat from the gas.
 
  How much work is done by the gas during this process? The ideal gas constant is R = 8.314 J/mol  K.
  A) -400 J B) -200 J C) 400 J D) 0.00 J E) 200 J

Question 2

Two radio antennas are 130 m apart on a north-south line. The two antennas radiate in phase at a frequency of 3.6 MHz. All radio measurements are made far from the antennas.
 
  The smallest angle, reckoned east of north from the antennas, at which constructive interference of two radio waves occurs, is closest to: A) 50
  B) 55
  C) 45
  D) 40
  E) 35

[bulacsom]

Answer to Question 1

D

Answer to Question 2

A

[NguyenJ]

Excellent

[Viet Thy]

Thanks for the timely response, appreciate it