# physics

posted by .

An insulated copper wire is wrapped around an iron nail. The resulting coil of wire consists of 240 turns of wire that cover 1.8 cm of the nail, as shown in the figure . A current of 0.61 A passes through the wire.
if the ferromagnetic properties of the nail increase the field by a factor of 120, what is the magnetic field strength inside the nail?

iv been trying for soo long but i have no idea , its a hmk question can someone explain to me , i have a test tomm

• physics -

• physics -

so n = 240 and i is 0,61??

and would the radius be 0.018/2??

• physics -

B=u0*I*N/L
u0=4pi*10^-7
I= .61A
N=240
L=.018m

B=.0102T
Multiply B times an increase of 120

## Similar Questions

1. ### physics

A piece of copper wire has a resistance per unit length of 6.45*10-3 /m. The wire is wound into a thin, flat coil of many turns that has a radius of 0.140 m. The ends of the wire are connected to a 12.0 V battery. Find the magnetic …

A student makes a magnet by winding wire around a nail and connecting the wire to a battery. Which end of the nail will be the north pole?
3. ### PHYSICS

1)A picture of width 40 cm weighing 40N hangs from a nail by means of flexible wire attached to the sides of the picture frame. The midpoint of the wire passes over the nail which is 3 cm higher than the points where the wire is attached …
4. ### chemistry

what is the chemical equation for these situations..?
5. ### chemistry

HELP PLEASE... what is the chemical equation for these situations..?
6. ### Bio

An electromagnet can be made by wrapping insulated wire around an iron nail and connecting the ends of the wire to a 6-volt battery. HYPOTHESIS: Increasing the number of coils of wire wrapped around the nail increases the strength …
7. ### need help

A picture of width 43.0 cm, weighing 52.0 N, hangs from a nail by means of flexible wire attached to the sides of the picture frame. The midpoint of the wire passes over the nail, which is 2.50 cm higher than the points where the wire …
8. ### physics need help bad

A picture of width 43.0 cm, weighing 52.0 N, hangs from a nail by means of flexible wire attached to the sides of the picture frame. The midpoint of the wire passes over the nail, which is 2.50 cm higher than the points where the wire …
9. ### physics help i still dont get it

A picture of width 43.0 cm, weighing 52.0 N, hangs from a nail by means of flexible wire attached to the sides of the picture frame. The midpoint of the wire passes over the nail, which is 2.50 cm higher than the points where the wire …
10. ### Science

So I did a science experiment and I have to wrap a coil wire around a nail and tap the other end to a battery. Then see how many paper clips will stick to the nail, and I had to wrap more coil wire around the nail over time and stuff …

More Similar Questions