You have a 7-m-long copper wire. you want to make an n-turn current loop that generates a 6.582 mt magnetic field at the center when the current is 4.092 a. you must use the entire wire. what will be the diameter of your coil?

0.042 m

Explanation:

L = length of the copper wire = 7 m

N = Number of turns in the current loop

B = magnetic field at the center = 0.006582 T

i = current flowing through the wire = 4.092 A

r = radius of the coil

length of the copper wire is given as

L = 2πrN

7 = 2πrN

rN = 1.115

                                            eq-1

Magnetic field at the center of the coil is given

r = 0.021 m

diameter is given as

d = 2r

d = 2 (0.021)

d = 0.042 m

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.