Question

The table shows the speed of ultrasound waves in different tissues in the human body.

The table shows the speed of ultrasound waves in different tissues in the human body.
Tissue Speed (m/s)
Air 330
Fat 1,450
Water 1,480
Liver 1,550
Kidney 1,560
Blood 1,570
Muscle 1,580
Bone 4,080
If an ultrasound wave moves from one tissue to another tissue in the body, which of the following transitions will result in the largest change in the wavelength of the ultrasound wave?

(1 point)
Responses

blood to fat
blood to fat

liver to muscle
liver to muscle

muscle to kidney
muscle to kidney

fat to liver

Answer 1

To determine which transition results in the largest change in wavelength for an ultrasound wave, we need to calculate the wavelength change using the formula:

\[
\text{Wavelength} = \frac{\text{Speed of Sound}}{\text{Frequency}}
\]

Since the frequency of the ultrasound wave remains constant regardless of the medium it is traveling through, the change in wavelength is directly proportional to the change in speed of sound in the different tissues. So, we can analyze the transitions based on the speed of sound in the tissues involved.

Let's calculate the speed differences for each transition:

1. **Blood to Fat**:
- Speed in Blood: 1,570 m/s
- Speed in Fat: 1,450 m/s
- Change: \(1,570 - 1,450 = 120 \, \text{m/s}\)

2. **Liver to Muscle**:
- Speed in Liver: 1,550 m/s
- Speed in Muscle: 1,580 m/s
- Change: \(1,580 - 1,550 = 30 \, \text{m/s}\)

3. **Muscle to Kidney**:
- Speed in Muscle: 1,580 m/s
- Speed in Kidney: 1,560 m/s
- Change: \(1,560 - 1,580 = -20 \, \text{m/s}\) (which is also a decrease)

4. **Fat to Liver**:
- Speed in Fat: 1,450 m/s
- Speed in Liver: 1,550 m/s
- Change: \(1,550 - 1,450 = 100 \, \text{m/s}\)

Now, we can summarize the changes:
- Blood to Fat: \(120 \, \text{m/s}\)
- Liver to Muscle: \(30 \, \text{m/s}\)
- Muscle to Kidney: \(-20 \, \text{m/s}\)
- Fat to Liver: \(100 \, \text{m/s}\)

The transition with the largest change in speed, and thus the largest change in wavelength, is from **Blood to Fat**, which has a change of **120 m/s**.

So the answer is:

**blood to fat**