Physics Answers

Q1: A power cycle capable of delivering a power output of 410 kJ for an energy input by heat transfer of 1000 kJ. The system undergoing the cycle receives the heat transfer from hot gases at a temperature of 500 K and discharges energy by heat transfer to the atmosphere at 27 °C. Evaluate: l amount of heat released from the system and thermal efficiency. 2 the efficiency if the system operates in Carnot cycle. 3 draw the schematic diagram of the system.

Three masses arranged as shown on the right where 𝑚𝐴 = 2.00 [kg], 𝑚𝐵 = 1.00 [kg], and 𝑚𝐶 = 3.00 [kg]. What is the location of the center of mass? 

 If the coefficient of friction between tires and roadway is 0.50, what is the smallest radius at which 

     a car can turn on a horizontal road when its speed is 30 miles/hour? 

. A power station conveyor lifts 500 tons of coal per hour to a height of 80 feet.  What average  

     horsepower is required? 

A stone is thrown at an initial speed of 125 ft/s directed 60

above the horizontal at the cliff of  

    height, y. The stone strikes the cliff 5.8 seconds after launching. Find the height of the cliff and 

    the speed of the stone just before impact at the top of the cliff. 

What is the resultant of a displacement 6.0 miles North and one 9.0 miles   East? 

IV. An iron wire 1.0 m long with a square cross-section 2.0 mm on a side is used  

              to support a 100 kg load. Find the change in length. 

VI. Find the maximum speed of a particle that undergoes SHM with a period of 

             0.50 s and an amplitude of 20 mm. 

Consider radium, which has a half-line of 1620 years. How many atoms of radium will decay in 5 s in 15 g of its sample? Consider the atomic weight of radium to be 226 kg/mol.

  IV. An iron wire 1.0 m long with a square cross-section 2.0 mm on a side is used  

              to support a 100 kg load. Find the change in length.