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
sergey [27]
3 years ago
11

A motor has an armature resistance of 3.75 Ω . Part A If it draws 9.10 A when running at full speed and connected to a 120-V lin

e, how large is the back emf?
Physics
1 answer:
bulgar [2K]3 years ago
4 0

Back emf is 85.9 V.

<u>Explanation:</u>

Given-

Resistance, R = 3.75Ω

Current, I = 9.1 A

Supply Voltage, V = 120 V

Back emf = ?

Assumption - There is no effects of inductance.

A motor will have a back emf that opposes the supply voltage, as the motor speeds up the back emf increases and has the effect that the difference between the supply voltage and the back emf is what causes the current to flow through the armature resistance.

So if 9.1 A flows through the resistance of 3.75Ω then by Ohms law,

The voltage across the resistance would be

v = I x R

  = 9.1 x 3.75

  = 34.125 volts

We know,

supply voltage = back emf + voltage across the resistance

By plugging in the values,

120 V = back emf + 34.125 V

Back emf = 120 - 34.125

                = 85.9 Volts

Therefore, back emf is 85.9 V.

You might be interested in
I need help with c-j !!
Tresset [83]

Answer:44

Explanation:

just add

8 0
3 years ago
As the distance between two objects increases, the gravitational force of attraction between them will
jeka94
That force DEcreases. This is a big part of the reason why the Earth attracts you with more force than Jupiter does.
4 0
3 years ago
I need help with this
lisabon 2012 [21]
A. Condensation

Hope this helps!!!
5 0
2 years ago
Need help on this please
Ratling [72]

question 2 answer is ALL OF THE ABOVE

question 3 answer is WARM AND MOIST.

8 0
3 years ago
In Trial III, a different, looser, spring is used; its force constant is 23.1 N/m. The suspended mass is the same as the one in
cricket20 [7]

Answer:

T=0.827s

Explanation:

The period of a spring can be calculated with the equation

T=2\pi w

But we know as well that w is given by,

w=\sqrt{\frac{k}{m}}

Replacing,

w=\frac{2\pi}{T}= \sqrt{\frac{k}{m}}\\T=2\pi\sqrt{\frac{k}{m}}\\T=2\pi\sqrt{\frac{0.4}{23.1}}

So we have that

T=0.827s

7 0
2 years ago
Other questions:
  • A rural mail carrier is driving slowly, putting mail in mailboxes near the road
    7·1 answer
  • Why is it that when a steadily flowing gas flows from a larger diameter pipe to a smaller diameter pipe, what causes the pressur
    10·1 answer
  • Get it right and win a brilliant
    8·1 answer
  • Calculate the acceleration of a mobile that at 4s is 32m from the origin, knowing that its initial speed is 10m / s.
    13·2 answers
  • What is the electric field at the center of the metal ball due only to the charges on the surface of the metal ball? (Express yo
    14·1 answer
  • How does the electric force between two charged particles change if the distance between them is increased by a factor of 2
    14·1 answer
  • Jason rides his bicycle 1,200 meters east to the grocery store. He then turns around and travels 760 meters west to meet his fri
    7·1 answer
  • Using the data provided below, calculate the corrected wavelength for a spectroscope reading of 6.32.
    8·1 answer
  • What will be the average velocity of a body falling in free fall on Earth for 3 s?
    7·1 answer
  • The ____ is a particle with one unit of positive change
    7·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!