the strength of a magnetic field around a wire carrying a current of 20 a is 0.004 t. what is the strength…

the strength of a magnetic field around a wire carrying a current of 20 a is 0.004 t. what is the strength of the magnetic field if the current is changed to 40 a?\n0.002 t\n0.004 t\n0.006 t\n0.008 t

the strength of a magnetic field around a wire carrying a current of 20 a is 0.004 t. what is the strength of the magnetic field if the current is changed to 40 a?\n0.002 t\n0.004 t\n0.006 t\n0.008 t

Answer

Explanation:

Step1: Identify the relationship

The magnetic - field strength $B$ around a current - carrying wire is directly proportional to the current $I$, i.e., $B = kI$ (where $k$ is a constant). So, $\frac{B_1}{I_1}=\frac{B_2}{I_2}$.

Step2: Substitute the given values

We know that $I_1 = 20A$, $B_1=0.004T$, and $I_2 = 40A$. Substituting into $\frac{B_1}{I_1}=\frac{B_2}{I_2}$, we get $B_2=\frac{I_2}{I_1}\times B_1$.

Step3: Calculate $B_2$

$B_2=\frac{40A}{20A}\times0.004T = 0.008T$.

Answer:

D. 0.008 T