## Q1. A heat engine receives heat from a source at 1100 K at a rate

Question Q1. A heat engine receives heat from a source at 1100 K at a rate of 400 kJ/s, and it rejects the waste heat to a medium at 320 K. The measured power output of the heat engine is 120 kW, and the environment temperature is 25 oC. Determine (a) the reversible power (b) the rate of irreversibility, and (c) the second law efficiency of this engine.

## Q2.Carbon dioxide initially at 50 kPa, 400 K, undergoes a process

Question Q2.Carbon dioxide initially at 50 kPa, 400 K, undergoes a process in a closed system until its pressure and temperature are 2 MPa and 800 K, respectively. Assuming an ideal gas behaviour, find the entropy change of the carbon dioxide by assuming that the specific heats are constant. For the gas, take Cp = 0.846 kJ/kg.K and R = 0.1889 kJ/kg.K

## A stretched string has a mass per unit length of 3.53 g/cm and a tension

Question A stretched string has a mass per unit length of 3.53 g/cm and a tension of 15.1 N. A sinusoidal wave on this string has an amplitude of 0.137 mm and a frequency of 63.2 Hz and is traveling in the negative direction of an x axis. If the wave equation is of the formy(x,t) = ym sin(kx ωt),what are (a) ym, (b) k, and (c) ω, and (d) the correct choice of sign in front of ω?

## Diagnostic ultrasound of frequency 4.63 MHz is used to examine tumors

Question Diagnostic ultrasound of frequency 4.63 MHz is used to examine tumors in soft tissue. (a) What is the wavelength in air of such a sound wave? (b) If the speed of sound in tissue is 1350 m/s, what is the wavelength of this wave in tissue? (Take the speed of sound in air to be 343 m/s.)

## Start accelerating at about 25 MPH (step on the gas). As your speedometer

Question Get Answer Start accelerating at about 25 MPH (step on the gas). As your speedometer passes through 30 MPH, record the acceleration. Have the driver continue the acceleration while you are making the reading. The driver can stop accelerating at 35 MPH or any safe speed above 30 MPH. In a later task this information will allow you to calculate the HP your engine is developing (the HP calculation is NOT part of this lab). 2- Repeat step 1 as you accelerate from 40 MPH past 45 MPH. Note that the acceleration you measure will be lower than the value you measured at 30 MPH. 3- Measure the deceleration of your car while the driver is braking to a stoplight or stop sign. Brake at a safe rate. Do not panic stop or brake in areas where other drives do not expect you to brake!

## 1. A 100kg rock is dragged up 30.0 degree incline plane with a

Question 1. A 100kg rock is dragged up 30.0 degree incline plane with a constant velocity. Determine the tension in the rope as well as the kinetic coefficient of friction between the rock and the ground.a. If the rope was to snap half way up the hill, at what rate would it accelerate down the incline? Assume you are using the kinetic coefficient of friction.