Answered

The table lists information about four devices.

\begin{tabular}{|c|c|c|c|}
\hline Device & Wire Loops & Current [tex]$(mA)$[/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]$W, X, Y, Z$[/tex]

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

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

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



Answer :

GinnyAnswer
To determine the order of devices from greatest to weakest magnetic field strength, we need to calculate the magnetic field strength for each device. The formula to use is:

[tex]\[ B = \text{loops} \times \text{current} \times \text{core multiplier} \][/tex]

Where the core multiplier is 1 if the device has a metal core, and 0 if it doesn't. Let’s calculate the magnetic field strength for each device:

1. Device W:
- Loops: 60
- Current: 0.0 mA (0.0 A)
- Metal Core: yes (core multiplier = 1)

[tex]\[ B_W = 60 \times 0.0 \times 1 = 0.0 \][/tex]

2. Device X:
- Loops: 40
- Current: 0.2 mA (0.2 A)
- Metal Core: yes (core multiplier = 1)

[tex]\[ B_X = 40 \times 0.2 \times 1 = 8.0 \][/tex]

3. Device Y:
- Loops: 30
- Current: 0.1 mA (0.1 A)
- Metal Core: no (core multiplier = 0)

[tex]\[ B_Y = 30 \times 0.1 \times 0 = 0.0 \][/tex]

4. Device Z:
- Loops: 20
- Current: 0.1 mA (0.1 A)
- Metal Core: no (core multiplier = 0)

[tex]\[ B_Z = 20 \times 0.1 \times 0 = 0.0 \][/tex]

The magnetic field strengths are:

- [tex]\( B_W = 0.0 \)[/tex]
- [tex]\( B_X = 8.0 \)[/tex]
- [tex]\( B_Y = 0.0 \)[/tex]
- [tex]\( B_Z = 0.0 \)[/tex]

Now, ordering the devices from the greatest to the weakest magnetic field strength, we get:

1. Device X with [tex]\( B_X = 8.0 \)[/tex]
2. Device W with [tex]\( B_W = 0.0 \)[/tex]
3. Device Y with [tex]\( B_Y = 0.0 \)[/tex]
4. Device Z with [tex]\( B_Z = 0.0 \)[/tex]

So, the correct order from greatest to weakest is:

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

Therefore, the correct answer is:

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