Five kg of butane (C4H10) in a piston–cylinder assembly undergo a process from p1 = 5 MPa, T1 = 500 K to p2 = 2 MPa, T2 = 450 K during which the relationship between pressure and specific volume is pvn = constant. Determine the work, in kJ.
In: Mechanical Engineering
a) A mass of 400 kg is to be raised by the actuation of two
identical hydraulic cylinders with a piston diameter of 120 mm.
Calculate the required system pressure to just raise the
load.
(b) If the load is to be raised 600 mm in 10 seconds, what will be
the required flowrate (Q) in l min–1?
In: Mechanical Engineering
The propane is contained in a piston-cylinder assembly, which maintains constant pressure at 0.2 MPa. If a mixture with a quality of 0.65 and a total volume of 0.07 m3 is slowly heated to a temperature of 54°C.
a) what was the total work into the system.
b) what was the total amount of heat added to the system.
In: Mechanical Engineering
One cylinder in the diesel engine of a truck has an initial volume of 600cm3 . Air is admitted to the cylinder at 25?C and a pressure of 1.0 atm. The piston rod then does 300J of work to rapidly compress the air.
Final temperature was calulated to be 610 degree celcius.
What is the final volume?
In: Physics
The number of arriving customers to a big supermarket is
following a Poisson distribution with a rate of 4 customers per a
minute.
What is the probability that no customer will arrive in a given
minute?
What is the probability that exactly 3 customers will arrive in a
given minute?
What is the probability that at least seven customer will arrive in
a given minute?
What is the probability that at most one customer will arrive in 40
seconds?
What is the average number of arriving customers in a given one
hour?
In: Statistics and Probability
The number of errors on a typed page is Poisson with mean 2.5 per page.
A. What is the probability that there are no errors on a page?
B. What is the probability mass function for X, the number of pages out of ten with no errors on it?
C. Find the exact and approximate probability that X=0.
D. A book of 100 pages has 95 pages with at least one error. Five pages are selected at random and without replacement. Let X denote the number of pages from the five that are selected that have no errors on it.
i) What is the exact and approximate probability that X is at least one?
ii) What are the mean and standard deviation of X?
In: Math
A construction worker riding an open elevator is moving upward with a speed of 6.0 m/s. When he is 42 m above the ground he accidentally drops a hammer. What are the maximum height reached by the hammer, the time it takes for the hammer to fall to the ground and speed of the hammer when it hits the ground? Please answer all parts, thank you!
In: Physics
Faradays Electromagnetic Lab – AC/DC Current and
Electromagnetism
Electromagnet
1. What happens to the speed of the current as you adjust the
voltage?
2. What happens to the magnetic field as you adjust the number of
loops?
3. What happens to the magnetic field when you switch to AC
voltage?
Transformer
1. Why doesn’t the transformer work with DC voltage?
2. What five things can you adjust to get the highest maximum
voltage?
Generator
1. What does RPM stand for?
2. What four things can you adjust to get the highest maximum
voltage?
In: Physics
Choose only 3 benefits of land being occupied by firms according to the principle of highest and best use (note that most of the options listed below do not arise from highest and best use):
a. Establishment of a working wage
b. Separation of industrial toxins from residential areas
c. Expanding tax base
d. Increased number of jobs
e. Vitality of locally owned businesses
f. Agglomeration
g. Improved community health
h. Greater potential for philanthropy
i. More complex division of labor
j. Situs
k. Balance of corporate businesses with smaller shops
In: Economics
| Is lack of sleep causing traffic fatalities? A study found that the average number of fatal crashes caused by drowsy drivers each year is 1550. Assume that annual number of fatal crashes is normally distributed with a standard deviation of 300. | |||||||
| a. What is the probability of fewer than 1000 fatal crashes a year due to drowsy drivers? | |||||||
| b. What is the probability of less than or equal to 1000 fatal crashes a year due to drowsy drivers? | |||||||
| c. Explain why your answers to parts a and b are equal. | |||||||
| d. What is the probability the number of fatal crashes will be between 1000 and 2000 for a year? | |||||||
| e. What is the probability of more than 1750 fatal crashes a year due to drowsy drivers? | |||||||
| f. What is the probability of no more than 1600 fatal crashes a year due to drowsy drivers? | |||||||
| g. Given that the probability of there being more than 1700 crashes per year is 0.31, use this information (not an Excel function) to find the probability of there being less than 1400 crashes per year due to drowsy drivers. | |||||||
| h. Explain how you determined your answer in part g using the given probability. | |||||||
| i. For a year to be in the upper 5% with respect to the number of fatal crashes, how many fatal crashes would have to occur? | |||||||
| j. Within what range evenly distributed around the mean are the number of fatal crashes that occur in 75% of the years? | |||||||
| lower: | upper: | ||||||
In: Statistics and Probability