An inventor claims to have developed a heat pump that produces 200 kW of heating for a 293 K heated zone whilst only using 75 kW of power and a heat source at 273 K. Using the max. theoretical efficiency of this device, justifythe validity of this claim. [5]

The two most prominent wavelengths in the light emitted by a hydrogen discharge lamp are 656(red) and 486 (blue). light from a hydrogen lamp illuminates a diffraction grating with 500 lines per mm, and the light is observed on a screen 1.50 behind the grating. what is the distance between the first-order red and blue fringes?