The table lists information about four devices.

\begin{tabular}{|c|c|c|c|}
\hline Device & Wire Loops & Current [tex][tex]$( mA )$[/tex][/tex] & Metal Core \\
\hline W & 60 & 0.0 & yes \\
\hline X & 40 & 0.2 & yes \\
\hline Y & 30 & 0.1 & no \\
\hline Z & 20 & 0.1 & no \\
\hline
\end{tabular}

Which lists the devices in order from greatest magnetic field strength to weakest?

A. [tex][tex]$W, X, Y, Z$[/tex][/tex]
B. [tex][tex]$W, Z, Y, X$[/tex][/tex]
C. [tex][tex]$X, Z, Y, W$[/tex][/tex]
D. [tex][tex]$X, Y, Z, W$[/tex][/tex]



Answer :

To determine the order of the devices from greatest magnetic field strength to weakest, we need to consider the factors provided: the number of wire loops, current, and the presence of a metal core.

1. Device W:
- Wire Loops: 60
- Current: 0.0 mA
- Metal Core: Yes
- Magnetic Field Strength: [tex]\( 60 \times 0.0 = 0 \times 2 \)[/tex] (with metal core) = 0

2. Device X:
- Wire Loops: 40
- Current: 0.2 mA
- Metal Core: Yes
- Magnetic Field Strength: [tex]\( 40 \times 0.2 = 8 \times 2 \)[/tex] (with metal core) = 16

3. Device Y:
- Wire Loops: 30
- Current: 0.1 mA
- Metal Core: No
- Magnetic Field Strength: [tex]\( 30 \times 0.1 = 3 \)[/tex]

4. Device Z:
- Wire Loops: 20
- Current: 0.1 mA
- Metal Core: No
- Magnetic Field Strength: [tex]\( 20 \times 0.1 = 2 \)[/tex]

Now let's compare and list the devices in order from greatest to weakest magnetic field strength:
- Device X: 16
- Device Y: 3
- Device Z: 2
- Device W: 0

Therefore, the correct order from greatest magnetic field strength to weakest is:

[tex]$X, Y, Z, W$[/tex]

So the correct option is:
[tex]$X, Y, Z, W$[/tex]