Answer:a substance with low ability or no ability to conduct energy
Explanation:
A simple electromagnet consisting of a coil of insulated wire wrapped around an iron core<span>. A </span>core<span> of ferromagnetic material like </span>iron<span> serves to increase the magnetic field created. The strength of magnetic field </span>generated<span> is proportional to the amount of </span>current<span> through the winding.</span>
C
the unit of electric current is the ampere, often shortened to amp
Answer:
0.5mv^2=50, v=5, 25/2×m=50, m=50×2/25, So, the answer is 4