HELP ASAP!!

A potential difference of 12 volts is induced across a straight wire 0.20 meters long as it is moved at a constant speed of 3.0 meters per second perpendicular to a uniform magnetic field. What is the strength of the magnetic field?

A

7.2 T

B

13 T

C

20. T

D

180 T

The strength of the magnetic field is equal to 20 Tesla.

Given:

Induced potential difference = V = 12 V

Length of wire = L = 0.20 m

Speed of the moving wire = V = 3.0 m/s

Magnetic field strength = B = ?

A conductor, placed in a uniform magnetic field; when moved at a constant speed with respect to the field, leads to a changing magnetic flux, generating an electromotive force (EMF). Using, Faraday's law of magnetic induction, a moving conductor's induced EMF in terms of the magnetic field strength is given by :

......................(1)

where

E = Induced potential difference (EMF)

L = Length of the conductor

V = Speed of the conductor moved with respect to the magnetic field

B = Strength of uniform magnetic field

Rewriting equation (1) for B, we get

The strength of magnetic field is equal to 20 Tesla.

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.

cancer risk hope this