Propane gas enters a continuous adiabatic heat exchanger’ at 40°C and 250 kPa and exits at 240°C superheated steam at 300°C and 5.0 bar enters the exchanger flowing counter currently to the propane and exits as a saturated liquid at the same pressure.
(a) Taking as a basis 100 mol of propane fed to the exchanger, draw and label a process flowchart. Include in your labeling the volume of propane fed (m3), the mass of steam fed (kg), and the volume of steam fed (m3).
(b) Calculate values of the labeled specific enthalpies in the following inlet—outlet enthalpy table for this process.
(c) Use an energy balance to calculate the required mass feed rate of the steam. Then calculate the volumetric feed ratio of the two streams (m3 steam fed/m3 propane fed). Assume ideal gas behavior for the propane but not the steam and recall that the exchanger is adiabatic.
(d) Calculate the heat transferred from the water to the propane (kJ/m3 propane fed). (Hint: Do an energy balance on either the water or the propane rather than on the entire heat exchanger.)
(e) Over a period of time, scale builds up on the heat transfer surface, resulting in a lower rate of heat transfer between the propane and the steam. What changes in the outlet streams would you expect to see as a result of the decreased heattransfer?

2.0 points At a particular instant, a stationary observer on the ground sees a package falling with speed v1 at an angle to the vertical. To a pilot flying horizontally at constant speed relative to the ground, the package appears to be falling vertically with a speed v2 at that instant. What is the speed of the pilot relative to
the ground?
1. √
v2 1 + v2
2
2. v2 − v1
3. √
v2 1 − v2
2
4. v1 + v2
5. v1 − v2
002 (part 1 of 2) 2.0 points A particle travels to the right at a constant rate of 6.2 m/s. It suddenly is given a vertical acceleration of 2.3 m/s2 for 4 s. What is its direction of travel after the
acceleration with respect to the horizontal? Answer between −180◦ and +180◦. Answer in units of ◦
003 (part 2 of 2) 2.0 points What is the speed at this time? Answer in units of m/s
004 2.0 points A particle moving at a velocity of 8.9 m/s in the positive x direction is given an accelera- tion of 5.9 m/s2 in the positive y direction for 3.7 s. What is the final speed of the particle? Answer in units of m/s
005 (part 1 of 3) 2.0 points
A particle moves in the xy plane with constant acceleration. At time zero, the particle is at x = 2 m, y = 6.5 m, and has velocity ~vo = (2.5 m/s) ı̂ + (−8.5 m/s) ̂ . The acceleration is given by ~a = (3.5 m/s2) ı̂+ (5 m/s2) ̂ . What is the x component of velocity after
1.5 s? Answer in units of m/s
006 (part 2 of 3) 2.0 points What is the y component of velocity after 1.5 s? Answer in units of m/s
007 (part 3 of 3) 2.0 points What is the magnitude of the displacement from the origin (x = 0 m, y = 0 m) after 1.5 s? Answer in units of m
008 (part 1 of 3) 2.0 points
A ball is thrown and follows the parabolic path shown. Point Q is the highest point on the path and points P and R are the same height above the ground.
Q
RP
How do the speeds of the ball at the three points compare? Air friction is negligible.
1. ‖~v Q ‖ < ‖~v
P ‖ = ‖~v
R ‖
2. ‖~v P ‖ < ‖~v
Q ‖ < ‖~v
R ‖
3. ‖~v P ‖ = ‖~v
R ‖ < ‖~v
Q ‖
4. ‖~v Q ‖ < ‖~v
R ‖ < ‖~v
P ‖
rouzbehani (mr39949) – Motion in 2D – bump – (1004) 2
5. ‖~v R ‖ < ‖~v
Q ‖ < ‖~v
P ‖
009 (part 2 of 3) 2.0 points Which diagram best indicates the direction of the acceleration, if any, on the ball at point R?
1.
2.
3.
4.
5.
6.
7.
8. The ball is in free fall and there is no acceleration at any point on its path.
9.
010 (part 3 of 3) 2.0 points Which diagram best indicates the direction of the net force, if any, on the ball at point Q?
1.
2.
3.
4.
5.
6. The ball is in free-fall and there is no acceleration at any point on its path.
7.
8.
9.
011 (part 1 of 3) 2.0 points A ball of mass 0.4 kg, initially at rest, is kicked directly toward a fence from a point 20 m away, as shown below. The velocity of the ball as it leaves the
kicker’s foot is 17 m/s at angle of 39 ◦ above the horizontal. The top of the fence is 4 m high. The ball hits nothing while in flight and air resistance is negligible. The acceleration due to gravity is 9.8 m/s2.
b
20 m
4 m
17 m /s
39 ◦
b
b
b
b
b
b
b
b
b
b
b
b
b
b
b
b
b
b
b
b
Determine the time it takes for the ball to reach the plane of the fence. Answer in units of s
012 (part 2 of 3) 2.0 points How far above the top of fence will the ball
pass? Consider the diameter of the ball to be negligible.
rouzbehani (mr39949) – Motion in 2D – bump – (1004) 3
Answer in units of m
013 (part 3 of 3) 2.0 points What is the vertical component of the velocity when the ball reaches the plane of the fence? Answer in units of m/s
014 2.0 points The velocity of a projectile at launch has a horizontal component vh and a vertical com- ponent vv. When the projectile is at the high- est point of its trajectory, identify the vertical and the horizontal components of its velocity and the vertical component of its acceleration. Consider air resistance to be negligible.
Vertical Horizontal Vertical Velocity Velocity Acceleration
1. vv 0 0
2. 0 vh 0
3. vv vh 0
4. 0 0 g
5. 0 vh g
015 2.0 points
A ball is thrown and follows the parabolic path shown. Air friction is negligible. Point Q is the highest point on the path. Points P and R are the same height above the ground.
Q
RP
How do the speeds of the ball at the three points compare?
1. ‖~v Q ‖ < ‖~v
R ‖ < ‖~v
P ‖
2. ‖~v R ‖ < ‖~v
Q ‖ < ‖~v
P ‖
3. ‖~v Q ‖ < ‖~v
P ‖ = ‖~v
R ‖
4. ‖~v P ‖ < ‖~v
Q ‖ < ‖~v
R ‖
5. ‖~v P ‖ = ‖~v
R ‖ < ‖~v
Q ‖
6. ‖~v P ‖ = ‖~v
R ‖ = ‖~v
Q ‖
016 2.0 points
A ball is thrown and follows the parabolic path shown. Air friction is negligible. Point Q is the highest point on the path. Points P and R are the same height above the ground.
Q
RP
Which of the following diagrams best indi- cates the direction of the acceleration, if any, on the ball at point P?
1.
2. The ball is in free-fall and there is no acceleration at any point on its path.
3.
4.
5.
rouzbehani (mr39949) – Motion in 2D – bump – (1004) 4
6.
7.
8.
9.
017 2.0 points
A ball is thrown and follows the parabolic path shown. Air friction is negligible. Point Q is the highest point on the path. Points P and R are the same height above the ground.
Q
RP
Which of the following diagrams best indi- cates the direction of the acceleration, if any, on the ball at point R?
1.
2.
3.
4.
5.
6.
7.
8. The ball is in free-fall and there is no acceleration at any point on its path.
9.
018 2.0 points
A bowling ball accidentally falls out of the cargo bay of an airliner as it flies along in a horizontal direction.
Z
Y
X
W
U
V
As observed by a person standing on the ground and viewing the plane as in the fig- ure, which path would the bowling ball most closely follow after leaving the airplane?
1. X
2. Y
3. V
4. U
5. Z
6. W
rouzbehani (mr39949) – Motion in 2D – bump – (1004) 5
019 2.0 points Aman can throw a ball a maximum horizontal distance of 169 m on a level field. The acceleration of gravity is 9.8 m/s2 . How far can he throw the same ball verti-
cally upward from the ground? (Assume that the ball is thrown from the ground and that his muscles give the ball the same speed in each case.) Answer in units of m
020 2.0 points Assume: A 78 g basketball is launched at an angle of 40.4◦ and a distance of 17.8 m from the basketball goal. The ball is released at the same height (ten feet) as the basketball goal’s height. A basketball player tries to make a long
jump-shot as described above. The acceleration of gravity is 9.8 m/s2 . What speed must the player give the ball? Answer in units of m/s
021 (part 1 of 3) 2.0 points A cannon sends a projectile towards a target a distance 1490 m away. The initial velocity makes an angle 39◦ with the horizontal. The target is hit. The acceleration of gravity is 9.8 m/s2 . What is the magnitude of the initial veloc-
ity? Answer in units of m/s
022 (part 2 of 3) 2.0 points How high is the highest point of the trajec- tory? Answer in units of m
023 (part 3 of 3) 2.0 points How long does it take for the projectile to reach the target? (Assume no friction) Answer in units of s
024 2.0 points If you are standing in a bus that moves at constant velocity and drop a ball from your outstretched hand, you will see its path as a vertical straight line.
How will the path appear to a friend stand- ing at the side of the road?
1. The path is a straight line slanted down.
2. The path is a straight line orientated vertically.
3. The path curves downward.
4. The path curves upward.
025 (part 1 of 2) 2.0 points A person can jump a horizontal distance of 2.55 m on the Earth. The acceleration of gravity is 5.91 m/s2 . How far could he jump on the Moon, where
the free-fall acceleration is 0.297g? Answer in units of m

Jupiter orbits the Sun at an average distance of 5.203 AU.
Part A – What is the length of its year in Earth years? Answer to two decimal places.
ANSWER:
Motion of Mars
Mars’s orbit is rather eccentric.
Part A – Does Mars move at a higher speed when it is farther away from the Sun or closer to it? Explain.
ANSWER:
Kepler’s 3rd Law
Part A – All of the following statements are true. Which one can be explained by Kepler’s third law?
ANSWER:
Tycho Brahe
Part A – The great contribution of Tycho Brahe was to
ANSWER:
3785 Character(s) remaining
Essay answers are limited to about 500 words (3800 characters maximum, including spaces).
(none provided)
Mars moves faster in its orbit when it is closer to the Sun than when it is farther from the Sun.
All the planets orbit the Sun in nearly the same plane.
Earth is slightly closer to the Sun in January than in July.
Venus orbits the Sun at a faster orbital speed than Earth.
The Sun is not in the precise center of Saturn’s orbit.
The Greeks
Part A – The ancient Greeks get a lot of attention for their contributions to science because
ANSWER:
Ellipses
Part A – Which of the following statements about an ellipse is NOT true?
ANSWER:
Eccentricities
Part A – When we say that a planet has a highly eccentric orbit, we mean that:
ANSWER:
Eris
possess a metal nose
discover four moons orbiting Jupiter, thereby lending strong support to the idea that Earth is not the center of the universe
offer the first detailed model of a Sun-centered solar system, thereby beginning the process of overturning the Earth-centered model of the Greeks
observe planetary positions with sufficient accuracy so that Kepler could later use the data to discover the laws of planetary motion
discover that planets orbit the Sun in elliptical orbits with varying speed
they were the first people to realize that Earth is a planet orbiting the Sun
they were the only ancient culture that kept written records of their astronomical observations
they were the first people known to try to explain nature with models based on reason and mathematics, without resort to the supernatural
the books of every other culture were lost in the destruction of the library of Alexandria
The semimajor axis of an ellipse is half the length of the longest line that you can draw across an ellipse.
The focus of an ellipse is always located precisely at the center of the ellipse.
An ellipse with a large eccentricity looks much more elongated (stretched out) than an ellipse with a small eccentricity.
A circle is considered to be a special type of ellipse.
it is spiraling in toward the Sun.
in some parts of its orbit it is much closer to the Sun than in other parts.
it has an odd but strangely endearing personality
its orbit is an ellipse with the Sun at one focus.
The recently discovered Kuiper Belt object Eris orbits the Sun every 557 years.
Part A – What is its average distance (semimajor axis) from the Sun in AU? Answer to one decimal place.
You did not open hints for this part.
ANSWER:
Tychonic Models
Part A – Which of the following is NOT true of Tychonic models of the universe?
ANSWER:
Perfecto!
Part A – Rank the following shapes in from most (left) to least perfect (right) according to the ancient Greeks.
You did not open hints for this part.
ANSWER:
The Moon orbits the Earth.
They gained widespread acceptance in Tycho’s time.
The Earth orbits the Sun.
The planets orbit the Sun.
The Sun orbits the Earth.
Reset Help
The correct ranking cannot be determined.
Circle Hexagon Square Decagon Octagon
Homocentric Models
Part A – Why does the homocentric model of Eudoxus have so many spheres? Explain how these spheres are attached to each other.
ANSWER:
Aristotle’s Model
Part A – Select all of the following which are NOT true of Aristotle’s model of the universe.
ANSWER:
Ptolemy vs. Copernicus
Part A – Describe the advantages of the model of Copernicus over that of Ptolemy. What are Copernicus’s lasting achievements?
ANSWER:
Greeks & Planetary Motion
Part A – Why did the ancient Greeks reject the real reason for planetary motion?
ANSWER:
3785 Character(s) remaining
Essay answers are limited to about 500 words (3800 characters maximum, including spaces).
(none provided)
The universe is divided into the celestial and sublunar worlds.
The celestial world is made of the elements of Earth, Wind, Fire, and Water.
The motion of all of the celestial spheres is derived from the Prime Mover.
The model fit Babylonian data quite well.
There are 56 celestial spheres.
The Prime Mover, the inner-most sphere, drives the motion of all the other spheres.
3785 Character(s) remaining
Essay answers are limited to about 500 words (3800 characters maximum, including spaces).