An electromagnet is a type of magnet in which the magnetic field is produced using the current. The simplest form of an electromagnet is a wire wrapped around in a coil.
The strength of magnetic field of such magnet is given with this equation:
![B=\frac{NI\mu}{L}](https://tex.z-dn.net/?f=B%3D%5Cfrac%7BNI%5Cmu%7D%7BL%7D)
Where N is the number of loops in the coil, I is the strength of the current flowing through the coil, L is the length of the coil, and
![\mu](https://tex.z-dn.net/?f=%20%5Cmu%20)
is <span>permeability of the electromagnet core material.
From this equation, we can see that increasing both the current and number of loops will increase the strength of the magnet.
Both BLANKS should be
Increase. When you use the additional battery you will have more voltage and more voltage means more electricity.</span>
Answer:
The answer is C. Abundant natural resources
Explanation:
A is wrong because humans cause pollution, B is wrong because we use natural resources and their supply would deteriorate, and D is wrong because we already break down rainforests and they are getting smaller.
If the current takes him downstream we must find the resultant vector of the velocities:
![V res= \sqrt{1^{2}+0.91^{2} } = \sqrt{1.8281}= 1.3520747](https://tex.z-dn.net/?f=V%20res%3D%20%5Csqrt%7B1%5E%7B2%7D%2B0.91%5E%7B2%7D%20%20%7D%20%3D%20%5Csqrt%7B1.8281%7D%3D%201.3520747%20)
Then if the river is 3000 m-wide the swimmer will have to pass:
1.3520747 · 300 = 4056.14 m t = 4056.14 m : 1 m/s
a ) It takes
4056.15 seconds ( 1 hour 7 minutes and 36 seconds ) to cross the river.
b ) 0.91 · 3000 =
2730 mHe will be 2730 m downstream.
a tendency of a body to do nothing or to remain unchanged.