A heat engine operates with sink temperature 25° with the efficiency of 30%. By how many kelvins should be raised for the source temperature to achieve an efficiency of 40%. (а) 78 K (b) 69 K (c) 52 K (d) 71 K

A heat engine operates with sink temperature 25° with the efficiency of 30%. By how many kelvins should be raised for the source temperature to achieve an efficiency of 40%. (а) 78 K (b) 69 K (c) 52 K (d) 71 K

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

See similar textbooks

Similar questions

A refrigerator works between temperatures TA = 105°C and TB = 5°C and has a quarter of the maximum coefficient of performance for these given temperatures. If the rate at which it receives the work is 30 W, how much heat does it absorb from the cooler environment in one minute? Choose the closest value. a) 1251.67 J b) 6.03 J c) 603.69 J d) 150 J
In a constant-volume process, 208 J of energy is transferred by heat to 1.07 mol of an ideal monatomic gas initially at 303 K. (a) Find the work done on the gas. (b) Find the increase in internal energy of the gas. (c) Find its final temperature. K
A nuclear power plant operates at 75 % of its maximum theoretical (Carnot) efficiency between temperatures of 645 °C and 380 °C. 1. If the plant produces electric energy at the rate of 1.6 GW, how much exhaust heat is discharged per hour?
(a) For the atmosphere, write down an expression for the first law of thermodynamics for an adiabatic process. (b) Write down an expression for change of internal energy of a system in a constant-volume (isosteric) process. (c) Determine the specific internal energy change and the work done during an isosteric cooling from 0°C to -10°C. (d)Determine the pressure level attained when a system expands adiabatically in the atmosphere from 1000 mb and temperature falls from 0°C to -10°C.
A refrigerator has a coefficient of performance of 2.36, runs on an input of 110W of electrical power, and keeps its inside compartment at 4.2°c. If you put a dozen 1.0- L plastic bottles of water at 28.2°C into this refrigerator, how long (in h) will it take for them to be cooled down to 4.2°C? (Ignore any heat that leaves the plastic.) Answer:
p (kPa) Он 400 5) The figure shows a pV diagram for a cycle of a heat engine for which Q, = 25 J. What is the thermal efficiency of the engine? 200 (Hint: remember to convert cm³ to m³!) A) 17% B) 34% C) 8.5% D) 64% E) 40% 100 V (em³) 200
A piston-cylinder assembly contains 0.7 lb of air initially at a pressure of 30 lbf/in² and a temperature of 100°F. The air is heated at constant pressure until its volume is doubled. Assume the ideal gas model with constant specific heat ratio, k = 1.4. Determine the work and heat transfer, in Btu.
Question 2. One of the most efficient engines ever built is a coal-fired steam turbine engine in the Ohio River valley, driving an electric generator as it operates between 1970°C and 530 C. (a) What is its maximum theoretical efficiency? (b) Its actual efficiency is 42.0%. How much mechanical power does the engine deliver if it absorbs 1.40 x 10°J of energy each second from the hot reservoir.
The gas cycled as shown. Calculate the heat supplied to the gas during the process C-A when QA-B = 20.0 J is the heat supplied during the process A-B, the process B-C is adiabatic and the total work done by the gas done during the cycle is 15.0 J?
In a certain thermodynamic process, 400 J of heat flows into a system, and at the same time the system expands against a constant external pressure of 8.00 × 10^4 Pa. If the volume of the system increases from 0.026 m^3 to 0.090 m^3, calculate the change in internal (thermal) energy of the system. If the internal (thermal) energy change is nonzero, be sure to indicate whether this energy change is positive or negative.
If heat absorbed by the engine = 15,000 Joule and Low temperature of 450 K High temperature of 850 K, what is the efficiency by the Carnot engine? Group of answer choices 52.94 % 47.06 % 15.34 % 74.50 %
A certain heat engine follows a cycle shown above. What is the thermodynamic work done by the process? Screen Shot 2021-04-12 at 2.18.38 PM(1).png ... 450000 400000 350000 300000 250000 200000 150000 100000 50000 0.05 0.1 0.15 0.2 0.25 0.3 Volume (m) A) 60,000 B 100,000 J c) 45,000 J D) 25,000J Pressure (Pa)