1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Rudiy27
2 years ago
7

The two major forces opposing the motion of a vehicle moving on a level road are the rolling resistance of the tires, Fr, and th

e aerodynamic drag force of the air flowing around the vehicle, Fd, given respectively by Fr, = fW, Fd= CdA1/2 rhoV2 where f and Cd are constants known as the rolling resistance coefficient and drag coefficient, respectively, W and A are the vehicle weight and projected frontal area, respectively, V is the vehicle velocity, and rho is the air density. For a passenger car with W = 3,550 lbf, A = 23.3 ft^2, and Cd = 0.34, and where f = 0.02 and rho = 0.08 lbm/ft^3.
Required:
Determine the power required, in HP, to overcome rolling resistance and aerodynamic drag when V is 55 mph.
Engineering
1 answer:
anzhelika [568]2 years ago
7 0

Answer:

The power required to overcome rolling resistance and aerodynamic drag is 19.623 h.p.

Explanation:

Let suppose that vehicle is moving at constant velocity. By Newton's Law of Motion, the force given by engine must be equal to the sum of the rolling resistance and the aerodynamic drag force of the air. And by definition of power, we have the following formula:

\dot W = \left(f\cdot W +\frac{\rho\cdot C_{D}\cdot A\cdot v^{2}}{2\cdot g_{c}} \right)\cdot v (1)

Where:

\dot W- Power, in pounds-force-feet per second.

f - Rolling resistance coefficient, no unit.

W - Weight of the passanger car, in pounds-force.

\rho - Density of air, in pounds-mass per cubic feet.

C_{D} - Drag coefficient, no unit.

A - Projected frontal area, in square feet.

v - Vehicle speed, in feet per second.

g_{c} - Pound-mass to pound-force ratio, in pounds-mass to pound-force.

If we know that f = 0.02, W = 3,550\,lbf, \rho = 0.08\,\frac{lbm}{ft^{3}}, C_{D} = 0.34, A = 23.3\,ft^{2}, v = 80.685\,\frac{ft}{s} and g_{c} = 32.174\,\frac{lbm}{lbf}, then the power required by the car is:

\dot W = \left(f\cdot W +\frac{\rho\cdot C_{D}\cdot A\cdot v^{2}}{2\cdot g_{c}} \right)\cdot v

\dot W = 10901.941\,\frac{lbf\cdot ft}{s}

\dot W = 19.623\,h.p.

The power required to overcome rolling resistance and aerodynamic drag is 19.623 h.p.

You might be interested in
Mahamad Siddiqui sent false emails and letters of recommendation on behalf of individuals without their permission to nominate h
shusha [124]

Mahamad Siddiqui sent false emails and letters of recommendation on behalf of individuals without their permission to nominate himself for the Waterman Award at the National Science Foundation. His earlier emails were offered where he had solicited letters were offered as evidence. Siddiqui claimed that content of earlier emails was hearsay. Do the earlier emails come in is given below

Explanation:

1.Mohamed Siddiqui appeals his convictions for fraud and false statements to a federal agency, and obstruction in connection with a federal investigation.   Siddiqui challenges the district court's admission into evidence of e-mail and foreign depositions.

2.On February 18, 1997, Jodi Saltzman, a special agent with the NSF interviewed Siddiqui at Siddiqui's office at the University of South Alabama.   During the interview, Siddiqui signed a statement admitting that he had nominated himself for the Waterman Award, but that he had permission from Yamada and von Gunten to submit forms on their behalf.   Siddiqui also acknowledged in the statement that Westrick had recommended Siddiqui for a different award, the PECASE Award, but that Siddiqui had changed the wording of the letter to apply to the Waterman Award.   Siddiqui was indicted on April 29, 1997.

3.Siddiqui opposed the taking of the depositions on the grounds that the witnesses' personal presence at trial was necessary, and that Indian travel restrictions for its citizens residing abroad prevented him from traveling to Japan and Switzerland.   Specifically, Siddiqui asserted that because of religious persecution in India his travel to Japan or Switzerland related to the criminal action would put his family members still living in India at risk.   The magistrate judge ruled that the government had carried its burden of showing that Yamada and von Gunten would be unavailable to appear at trial, and instructed that Siddiqui's fear of obtaining a travel visa from India because of the threat of persecution of family members should not preclude the taking of the foreign depositions.

4.Yamada's deposition was taken in Japan on March 6, 1998.   At government expense, Siddiqui's counsel attended the deposition and cross-examined the witness, but was not in telephonic contact with Siddiqui during the deposition.   Yamada testified that on February 1, 1997, she received an e-mail stating that if she received a phone call from the NSF to “please tell good words about me.”   Yamada testified that she knew the e-mail was from Siddiqui because the name on the e-mail had Siddiqui's sender address, and it ended with the name “Mo” which Siddiqui had previously told her was his nickname, and which he had used in previous e-mail.

5.Yamada later admitted to Saltzman that she had not given Siddiqui permission to sign, but had made the earlier representation because she thought Siddiqui would go to jail.

6.During cross-examination of Yamada at the deposition, Siddiqui's counsel introduced an e-mail from Yamada to Siddiqui.   This e-mail contained the same e-mail address for Siddiqui as the e-mail received by Yamada and von Gunten apparently from Siddiqui.

7.Von Gunten's video deposition was taken in Switzerland.   At government expense, Siddiqui's counsel attended the deposition and cross-examined von Gunten.   During the deposition, Siddiqui was in communication with his counsel by telephone.   Von Gunten testified at the deposition that he had not submitted a letter of recommendation in favor of Siddiqui for the Waterman Award, and that he had not given Siddiqui permission to submit such a letter in his name.

8 0
3 years ago
What are the advantages of triggering circuit<br> for thyrestors?
sergejj [24]

Answer:

For most applications, it is simple, dependable, efficient, and straightforward to apply - a simple trigger signal may be provided, with appropriate processing if necessary. This implies that an appropriate trigger signal may be generated using other electrical circuits and then applied to the SCR.

Explanation:

3 0
2 years ago
The Chinese had a toy helicopter some 1000 years ago. True Or False ?
Vadim26 [7]

Answer:

f

Explanation:

for the lazy people

5 0
2 years ago
List and briefly describe two modern's materials needs
Angelina_Jolie [31]

Answer:

Modern and smart materials for making the products are improved by developing new materials and find new uses for the existing. As, modern industrialization society is increased demand and quality of the product.

Two modern's materials are:

Carbon Fiber: As, carbon fiber is a strong material and it is light in weight. Designers used it because it is five times strong as steel and two times as stiff. Carbon fiber is basically made out of very thin strands of carbon.

Fiber Optics: It is a new technology as, it is used as transparent solid to transmitted light signals.

4 0
3 years ago
Javier is well versed in computer-aided design and is adept at spatial reasoning. What other skill would be
snow_tiger [21]
Surveying and cartography
5 0
2 years ago
Read 2 more answers
Other questions:
  • A thin-walled tube with a diameter of 6 mm and length of 20 m is used to carry exhaust gas from a smoke stack to the laboratory
    7·1 answer
  • A bar having a length of 5 in. and cross-sectional area of 0. 7 in.2 is subjected to an axial force of 8000 lb. If the bar stret
    9·1 answer
  • A thick spherical pressure vessel of inner radius 150 mm is subjected to maximum an internal pressure of 80 MPa. Calculate its w
    9·1 answer
  • Consider a 5 m long, air-filled section of a coaxial transmission line, given that the radius of the inner conductor is 10 cm an
    7·1 answer
  • An equal-tangent sag vertical curve (with a negative initial and a positive final grade) is designed for 55 mi/h. The PVI is at
    5·1 answer
  • Write a program to calculate overtime pay of 10 employees. Overtime is paid at the rate of Rs. 12.00
    13·1 answer
  • Unitate de masura in SI pt F​
    11·1 answer
  • -Electronic control modules can easily evaluate the voltage and current levels of circuits to which they are connected and deter
    15·1 answer
  • determine the position d of the 6- kn load so that the average normal stress in each rod is the same.
    15·1 answer
  • You need to lift a 2012 toyota highlander and haven't done so in a while. which of these are reliable sources for checking the c
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!