| Tag Archive | magnetic field

someone pls help with these last physics questions asap!? 10pts?

Sunday, September 4, 2011

PLEASE HELP WITH THESE QUIZ QUESTIONS Question 36 Which of the following is used in an electric power station to minimize the power loss in an electric power transmission? ac generator step-up transformer step-down transformer dc motor Question 37 Which of the following electro-magnetic radiations has the shortest wavelength? microwaves x rays gamma rays radio [...]

someone pls help asap!? physics 10pts?

Saturday, September 3, 2011

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I NEED HELP WITH THESE QUIZ QUESTIONS ASAP PLEASE Question 22 A step-down transformer used on an 800 V line has 100 turns on the primary. What is the emf produced on the secondary coil if the turns on it are 40 turns? 200 V 320 V 2000 V 4000 V Question 23 The maximum [...]

Urgent question about electric generators?

Friday, September 2, 2011

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So does an electric generator produce current when a magnet is making contact with the coil, or is it just the magnetic field? Do generator run out, or go bad (say because the magnet loses its magnetism, or the coil wears down)? Does it matter what the coil is made of (nickel, copper, aluminum, etc.)

In a huge electrical generator, how is the initial magnetic field produced in the NON permanent magnets?

Thursday, August 11, 2011

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I understand when the copper coil spins within the magnetic field, the current is produced. I just dont know how the magnets that are NOT permanent magnets get magnetised initially???????

What is the maximum emf output?

Monday, August 8, 2011

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A student makes a simple ac generator by using a single square wire loop 11 cm on a side. The loop is then rotated at a frequency of 60Hz in a magnetic field of 1.6×10−2 T. What is the maximum emf output?

Two generators use the same magnetic field and operate at the same frequency. Each has a single-turn circular?

Tuesday, August 2, 2011

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Two generators use the same magnetic field and operate at the same frequency. Each has a single-turn circular coil. One generator has a coil radius of 3.8 cm and a peak emf of 1.8 V. The other generator has a peak emf of 3.9 V. Find the coil radius r of this other generator.

A rectangular loop with 100 turns and area of 0.12 m2 rotates at 100 rad/s. The axis of rotation of the square?

Monday, August 1, 2011

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A rectangular loop with 100 turns and area of 0.12 m2 rotates at 100 rad/s. The axis of rotation of the square is perpendicular to the direction of the magnetic field of 0.025 Tesla. What is the maximum emf induced in the loop? The emf produced in a generator is What is the frequency of [...]

what must the value of f be for the maximum induced potential difference to be 210 V?

Sunday, July 31, 2011

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A simple generator consists of a loop rotating inside a constant magnetic field (see figure below). If the loop is rotating with frequency f, the magnetic flux is given by Φ(t) = BA cos (2πft). If B = 5 T and A = 6 m2, what must the value of f be for the maximum [...]

What is the strength of the magnetic field?

Friday, July 29, 2011

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A generator consists of 10 turns of wire, and each turn has an area of 0.095^2 m. If a maximum emf of 120V is induced when the coil rotates with a frequency of 60Hz, what is the strength of the magnetic field? a- 0.85 T b- 0.34 T c- 0.15 T d- 1.5 T Its [...]

Quantifying the emf induced in a generator?

Wednesday, July 27, 2011

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A generator is made from a set of 7000 loops of area 5.00 cm2 rotating at an angular frequency of 600 radians per second. The magnetic field is created by a solenoid, completely surrounding the generator coil, and carrying a current of 0.600 A. How many turns per unit length must the solenoid have in [...]