10 points!! Desperate on this physics problem!!!?

Question

A single circular loop of wire with radius .020 m carries a current of 8.0 A. It is placed at the center of a solenoid that has a length of .65 m radius .080 m and 1400 turns.

Determine the value of the current in the solenoid so that the magnetic field at the center of the loop is zero tesla.

Determine the magnitude of the total magnetic field at the center of the loop (due both to the loop and the solenoid) if the current in the loop is reversed in direction from that needed to make the total field equal to zero tesla.

Answer 1

Okay so which way is the loop facing?



I'm going to assume that its concentric with the axis of the solenoid.



So you want the current from the circular loop to oppose the solenoid



Equation for loop. B = µI/2R



so B = (µ/2)(8/.02) = 200µ



Equation for Solenoid. B = µnI



so B = µ(1400/.65)I = 28000/13µI



If we set the two equal 200µ = 28000/13µI



I = 0.092857 A



So then for part two, we would plug back in the current to the solenoid equation, and add the two together. However, we can also just double the value of the loop



Part two = 400µ



I don't have the value of mu memorized, you will have to look it up on wikipedia or something.

Answer 2

merely use conservation of momentum; The slidding marble's preliminary momentum "m1v1" plus the marble's momentum it catches m2v2 equivalent to the suitable momentums of the two marbles m1u1 & m2u2; m1v1 + m2v2 = m1u1 + m2u2 merely remedy this for "u1" . If it comes out helpful its shifting to the properly suited. If it comes out adverse its shifting to the left.

Answer 3

type the problem on google, the answer might pop up.

Answer 4

go to youtube or Google