An archer shoots an arrow horizontally. After 4 seconds it lands on the ground 520m away from the archer. a) What is the horizontal velocity of the arrow when it is released?
b) What is the actual velocity of the arrow when it hits the ground?

Two kilograms of air within a piston–cylinder assembly executes a carnot power cycle with maximum and minimum temperatures of 800 k and 300 k, respectively. the heat transfer to the air during the isothermal expansion is 60 kj. at the end of the isothermal expansion the volume is 0.4 m3. assume the ideal gas model for the air. determine the thermal efficiency, the volume at the beginning of the isothermal expansion, in m3, and the work during the adiabatic expansion, in kj.