Sound, ultrasound and measurement

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Catatan pelajaran

Big idea: sound, ultrasound and measurement

Key concept: Relationships. Sound is a longitudinal wave requiring a medium. Echo distance equals sound speed times round-trip time divided by two.
Related concepts: Models and evidence. Use a scientific explanation to make predictions, then test it against observations.
Global context: Scientific and technical innovation. Ultrasound supports distance measurement and imaging.

Sound Waves

Sound waves are longitudinal waves produced by vibrating sources.
They require a medium (solid, liquid, gas) to travel; cannot travel through a vacuum.
Longitudinal waves consist of compressions (regions of higher density) and rarefactions (regions of lower density).
Sound is a pressure wave; compressions and rarefactions cause pressure variations.
When sound hits a solid, the pressure variations cause the solid to vibrate in sync with the wave.

A diagram illustrating compressions and rarefactions in a sound wave generated by a vibrating solid.

Measuring the Speed of Sound

Speed of sound in air: 330–350 m/s (increases with temperature).
Sound travels fastest in solids (~5000 m/s), slower in liquids (~1500 m/s), slowest in gases.
Experiment 1 (two-point method): Measure distance (e.g., 100 m) and time (stopwatch) between a sound source and observer. Speed = distance / time.
Experiment 2 (oscilloscope method): Two microphones connected to an oscilloscope, distance ~2 m. Clap near first mic; oscilloscope measures time difference. More accurate than stopwatch.
Accuracy: Experiment 2 is more accurate because timing is automatic; Experiment 1 suffers from human reaction time (~0.2 s error).
Use repeat readings and larger distances to reduce random errors.

Experiment setup for measuring the speed of sound using two microphones and an oscilloscope.

Effects of Sound Waves

Pitch depends on frequency: high frequency → high pitch; low frequency → low pitch.
Loudness depends on amplitude: large amplitude → loud sound; small amplitude → quiet sound.
Echoes are reflections of sound waves off hard, flat surfaces.
Distance to reflecting surface: distance = ½ × speed × time (time is total for sound to travel to surface and back).

A person clapping to create an echo off a wall, while another person times the event.

Ultrasound

Human hearing range: 20 Hz – 20,000 Hz (20 kHz).
Ultrasound is sound with frequency above 20 kHz.
Ultrasound is partially reflected at boundaries between different media.
Uses: medical scanning (foetus, soft tissues), non-destructive testing (detecting cracks in metal), sonar (depth measurement).
Depth calculation: depth = ½ × speed × time (same as echo formula).
Ultrasound is non-invasive and considered harmless.

Think like a scientist

Use a teacher-operated ultrasonic distance sensor to compare echo return times for a target at different measured distances.
Comparison: the target distance. Outcome: the echo round-trip time.
Control: keep the medium and temperature approximately constant. Explain why this makes the comparison fairer.
Evidence: Use a consistent method, repeated observations where appropriate and a table with labelled quantities and units. Keep unexpected results and investigate their cause.
Safety: Practical activities need teacher supervision and an appropriate risk assessment. Use the provided data or simulation where the investigation specifies it.
Inquiry task: State a testable question, predict the outcome using the science, then explain how your observations would support or challenge the prediction.

Evaluate the science

Ultrasound supports distance measurement and imaging.
Changing temperature, target angle or reflective surface can affect the measurement; a missing echo does not prove the target is absent.
Evaluation task: Link your conclusion to evidence, identify a limitation and suggest a specific improvement. Distinguish a measured result from an explanation of its cause.

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1.Which of the following frequency ranges is completely audible by a human with average hearing?
Easy
- A200 Hz to 200 kHz
- B5 Hz to 50 kHz
- C50 Hz to 5 kHz
- D50 kHz to 50 MHz
2.A tuba player plays a loud note on her tuba. She then plays a quiet note of the same pitch. Which property of the sound wave she produced has changed?
Easy
- AFrequency
- BWavelength
- CAmplitude
- DSpeed
3.A high frequency note is played on a violin. The violinist then reduces the frequency of the note. What change in the note do the audience hear?
Easy
- APitch increases
- BPitch decreases
- CVolume increases
- DVolume decreases
4.Sound wave W has amplitude A and frequency f. Sound wave X is louder and lower in pitch than sound wave W. What can be said about the amplitude and frequency of sound wave X?
Easy
- AAmplitude higher than A, frequency higher than f
- BAmplitude higher than A, frequency lower than f
- CAmplitude lower than A, frequency higher than f
- DAmplitude lower than A, frequency lower than f
5.Which of the following is not a use of ultrasound?
Easy
- AScanning a fetus during pregnancy
- BNon-destructive testing of materials such as to find leaks in copper pipes
- CMapping with sonar
- DIdentifying broken bones
6.When objects vibrate, they produce sound waves. An object in a room vibrates. However, a person in that same room does not hear anything. Why not?
Easy
- AThe room contains no air.
- BThe sound waves are travelling too fast.
- CThe amplitude of the sound waves is too great.
- DThe frequency of the sound waves is too great.
7.After a lockdown drill, the management notes the siren is too quiet and its pitch is too low. They ask the company to make the alarm louder and give it a higher pitch. What effect does this have on the resulting sound wave?
Easy
- AIt has a larger amplitude and a lower frequency.
- BIt has a larger frequency and a lower amplitude.
- CIt has a smaller frequency and a larger amplitude.
- DIt has a larger frequency and a larger amplitude.
8.A teacher uses a signal generator connected to a speaker to make sounds of different frequencies. Which frequency can be heard by a student?
Easy
- A10 Hz
- B30 kHz
- C440 Hz
- D120 kHz

Soal lainnya

9.In physics, which wave property causes an echo?
Easy
- AReflection
- BRefraction
- CDiffraction
- DDispersion
10.A student stands 60 m from a wall. Sound travels at 300 m/s. How long after a clap does the echo return?
Easy
- A0.20 s
- B0.40 s
- C2.5 s
- D5.0 s
11.A pulse of sound is produced at the bottom of a boat. The sound travels through water, reflects from the sea bed, and returns after 1.3 s. The sea bed is 1000 m below the boat. What is the speed of sound in water?
Medium
- A770 m/s
- B1300 m/s
- C1500 m/s
- D2600 m/s
12.A student stands at a distance d from a wall. He claps his hands and hears an echo 1.2 s later. What is the approximate value of d? (Speed of sound = 340 m/s)
Medium
- A50 m
- B100 m
- C200 m
- D400 m
13.A student claps her hands 170 m from a tall building. She hears the echo 1.0 s later. What is the speed of sound in air?
Medium
- A340 m/s
- B170 m/s
- C85 m/s
- D680 m/s
14.A boat uses sonar to detect a submarine. The sonar emits a pulse of sound and receives the echo 0.48 s later. The speed of sound in water is 1500 m/s. How far is the submarine from the boat?
Medium
- A360 m
- B720 m
- C1563 m
- D3125 m
15.An ultrasound pulse is sent into a steel bolt to check for internal cracks. The oscilloscope trace shows a pulse reflected from a crack 5 divisions after the initial pulse. Each division represents 0.000002 s. The speed of sound in steel is 6000 m/s. What is the distance from the head of the bolt to the crack?
Hard
- A3 cm
- B6 cm
- C0.03 m
- D0.06 m
16.A student uses two microphones connected to an oscilloscope to measure the speed of sound. The microphones are placed 2.0 m apart. A clap is made near the first microphone. The oscilloscope shows that the sound reaches the second microphone 0.0059 s later. What is the speed of sound?
Medium
- A339 m/s
- B340 m/s
- C342 m/s
- D344 m/s
17.A sound wave travels from air into water. The speed of sound in air is 340 m/s and in water is 1500 m/s. If the frequency of the wave is 500 Hz in air, what is its frequency in water?
Medium
- A500 Hz
- B2205 Hz
- C113 Hz
- D1500 Hz
18.A student stands at a distance d from a wall and claps. She hears the echo after 1.2 s. The speed of sound is 340 m/s. What is d?
Medium
- A204 m
- B408 m
- C102 m
- D510 m
19.A ship uses sonar to measure the depth of the ocean. A pulse of sound is sent downward and the echo is received 2.0 s later. The speed of sound in water is 1500 m/s. What is the depth of the ocean?
Medium
- A1500 m
- B3000 m
- C750 m
- D375 m
20.Which of the following is a correct use of ultrasound?
Easy
- AMedical scanning of a fetus
- BMeasuring the speed of light
- CDetermining the colour of an object
- DAmplifying sound waves
21.A student measures the speed of sound by clapping two blocks together 100 m from a wall and timing the echo. Which change would improve the accuracy of the measurement?
Medium
- AUsing a larger distance
- BUsing a smaller distance
- CUsing a louder clap
- DUsing a higher frequency clap
22.An oscilloscope is used with two microphones to measure the speed of sound. The microphones are 3.0 m apart. The oscilloscope trace shows the sound arrives at the second microphone 0.0088 s after the first. What is the speed of sound?
Medium
- A341 m/s
- B340 m/s
- C342 m/s
- D339 m/s
23.A sound wave has a frequency of 256 Hz and a wavelength of 1.33 m in air. What is the speed of sound in air?
Easy
- A340 m/s
- B192 m/s
- C341 m/s
24.A student uses a method to measure the speed of sound by clapping two blocks together and timing the echo from a wall. The measured time is 0.6 s for a distance of 102 m. The actual speed of sound is 340 m/s. What is the percentage error in the student's measurement?
Hard
- A0%
- B0.6%
- C1.0%
- D0.3%
25.In an experiment to measure the speed of sound, a student stands 100 m from a wall and claps two wooden blocks together. She starts a stopwatch when she sees the clap and stops it when she hears the echo. The measured time is 0.60 s. What is the speed of sound calculated from these measurements?
Medium
- A333 m/s
- B167 m/s
- C600 m/s
- D300 m/s
26.Which of the following is the main source of error in the method of measuring the speed of sound using a stopwatch and two people at a known distance?
Easy
- AThe trundle wheel may not measure distance accurately
- BHuman reaction time when starting and stopping the stopwatch
- CThe wooden blocks may not produce a loud enough sound
- DThe speed of sound varies with wind direction
27.A student uses two microphones connected to an oscilloscope to measure the speed of sound. The microphones are placed 2.0 m apart. A clap is made near the first microphone. The oscilloscope trace shows the sound reaches the first microphone at time t = 0 and the second microphone at t = 5.8 ms. What is the speed of sound?
Medium
- A345 m/s
- B290 m/s
- C3450 m/s
- D1160 m/s
28.In an experiment to measure the speed of sound using an oscilloscope, which of the following is a control variable?
Easy
- ADistance between microphones
- BTime for sound to travel between microphones
- CThe set of microphones used
- DThe speed of sound
29.Which type of wave is a sound wave?
Easy
- ATransverse
- BLongitudinal
- CElectromagnetic
- DStationary
30.What is the approximate range of audible frequencies for a healthy human ear?
Easy
- A20 Hz to 20000 Hz
- B200 Hz to 20000 Hz
- C20 Hz to 2000 Hz
- D20 kHz to 200 kHz
31.Complete the sentence:
Easy
Sound waves are produced by ____ sources.
32.A student claps his hands 170 m from a tall building and hears the echo 1.0 s later. What is the speed of sound in air?
Easy
33.State what is meant by ultrasound.
Easy
34.Complete the sentence about sound waves.
Easy
Sound waves are produced by ____ sources and require a ____ to travel through.
35.Which of the following is necessary for sound to travel?
Easy
- AA vacuum
- BA medium
- CLight
- DElectricity
36.A sound wave has frequency 500 Hz and speed 340 m/s. What is the distance between neighbouring compressions?
Easy
- A0.68 m
- B1.47 m
- C160 m
- D840 m
37.Sound travels at different speeds in different materials. In which of the following does sound travel fastest?
Easy
- AGas
- BLiquid
- CSolid
- DVacuum
38.Which statement about ultrasound is correct?
Easy
- AUltrasound has a frequency higher than 20 kHz.
- BUltrasound has a frequency lower than 20 Hz.
- CUltrasound is used in radar systems.
- DUltrasound can travel through a vacuum.
39.Sound waves are transverse waves.
Easy
True or false?
40.A compression is a region of lower density in a longitudinal wave.
Easy
True or false?
41.Use a teacher-operated ultrasonic distance sensor to compare echo return times for a target at different measured distances. What is the independent variable?
Easy
- Athe echo round-trip time
- Bthe target distance
- Cthe number of repeated trials
- Dthe scientific explanation written afterwards
42.Use a teacher-operated ultrasonic distance sensor to compare echo return times for a target at different measured distances. Which observation or quantity is the dependent variable?
Easy
- Athe target distance
- Bthe title given to the investigation
- Cthe echo round-trip time
- Dthe number of references in the report
43.Use a teacher-operated ultrasonic distance sensor to compare echo return times for a target at different measured distances. Which decision best controls another factor in this comparison?
Medium
- Achange every condition for each trial
- Buse a different measurement method for every result
- Crecord only results that agree with the prediction
- Dkeep the medium and temperature approximately constant
44.Use a teacher-operated ultrasonic distance sensor to compare echo return times for a target at different measured distances. Why should the class repeat measurements or check multiple comparable observations?
Medium
- ATo assess variation and judge how consistent the evidence is
- BTo guarantee that every systematic error disappears
- CTo make an unsupported prediction become correct
- DTo avoid reporting results that disagree with a model
45.A class is evaluating an application of sound, ultrasound and measurement. Which statement identifies a relevant limitation?
Hard
- AAll scientific models reproduce every feature of the real world
- BChanging temperature, target angle or reflective surface can affect the measurement; a missing echo does not prove the target is absent.
- COne favourable result proves that a technology has no disadvantages
- DA conclusion needs no evidence when a scientific term is used
46.Use a teacher-operated ultrasonic distance sensor to compare echo return times for a target at different measured distances. Which conclusion is most justified by a controlled comparison?
Hard
- AA claim that the result must hold in all possible conditions
- BA claim that alternative explanations never need testing
- CA conclusion restricted to the tested conditions, with uncertainty and limitations stated
- DA claim based only on the most convenient observation
47.Use a teacher-operated ultrasonic distance sensor to compare echo return times for a target at different measured distances. Select the two practices that strengthen the validity of this comparison.
Medium
- Akeep the medium and temperature approximately constant
- Bchange the measurement method whenever a result is unexpected
- Crecord the echo round-trip time using the same agreed procedure
- Dreport only observations that confirm the prediction
48.When evaluating evidence about sound, ultrasound and measurement, select the two scientifically defensible statements.
Hard
- AOne result proves the explanation in every situation
- BChanging temperature, target angle or reflective surface can affect the measurement; a missing echo does not prove the target is absent.
- CA conclusion should state the conditions and uncertainty of the evidence
- DModels never need revision when new evidence appears
49.Design a fair investigation for this question: Use a teacher-operated ultrasonic distance sensor to compare echo return times for a target at different measured distances. Identify what to compare, what to record and one control.
Medium
50.Explain one use of the science in sound, ultrasound and measurement and evaluate one limitation of the evidence or application.
Hard
51.An echo returns after 0.080 s. Use sound speed 340 m/s. What is the one-way distance to the reflecting surface?
Hard
- A27.2 m
- B4.25 m
- C680 m
- D13.6 m
52.An ultrasonic sensor assumes sound speed 340 m/s, but the actual speed is higher. For a fixed target, how does this affect its calculated distance from the measured echo time?
Hard
- AIt underestimates distance because the assumed speed is too low
- BIt overestimates distance because the assumed speed is too low
- CIt cannot affect the result because time is measured
- DIt makes every echo travel only one way

Catatan ulasan

## Big idea: sound, ultrasound and measurement - **Key concept: Relationships.** Sound is a longitudinal wave requiring a medium. Echo distance equals sound speed times round-trip time divided by two. - **Related concepts: Models and evidence.** Use a scientific explanation to make predictions, then test it against observations. - **Global context: Scientific and technical innovation.** Ultrasound supports distance measurement and imaging. ## Sound Waves - Sound waves are **longitudinal** waves produced by vibrating sources. - They require a **medium** (solid, liquid, gas) to travel; cannot travel through a vacuum. - Longitudinal waves consist of **compressions** (regions of higher density) and **rarefactions** (regions of lower density). - Sound is a **pressure wave**; compressions and rarefactions cause pressure variations. - When sound hits a solid, the pressure variations cause the solid to vibrate in sync with the wave. ## Measuring the Speed of Sound - Speed of sound in air: **330–350 m/s** (increases with temperature). - Sound travels fastest in **solids** (~5000 m/s), slower in **liquids** (~1500 m/s), slowest in **gases**. - **Experiment 1 (two-point method)**: Measure distance (e.g., 100 m) and time (stopwatch) between a sound source and observer. Speed = distance / time. - **Experiment 2 (oscilloscope method)**: Two microphones connected to an oscilloscope, distance ~2 m. Clap near first mic; oscilloscope measures time difference. More accurate than stopwatch. - **Accuracy**: Experiment 2 is more accurate because timing is automatic; Experiment 1 suffers from human reaction time (~0.2 s error). - Use **repeat readings** and **larger distances** to reduce random errors. ## Effects of Sound Waves - **Pitch** depends on **frequency**: high frequency → high pitch; low frequency → low pitch. - **Loudness** depends on **amplitude**: large amplitude → loud sound; small amplitude → quiet sound. - **Echoes** are reflections of sound waves off hard, flat surfaces. - Distance to reflecting surface: **distance = ½ × speed × time** (time is total for sound to travel to surface and back). ## Ultrasound - Human hearing range: **20 Hz – 20,000 Hz** (20 kHz). - **Ultrasound** is sound with frequency **above 20 kHz**. - Ultrasound is partially reflected at boundaries between different media. - **Uses**: medical scanning (foetus, soft tissues), non-destructive testing (detecting cracks in metal), sonar (depth measurement). - Depth calculation: **depth = ½ × speed × time** (same as echo formula). - Ultrasound is **non-invasive** and considered harmless. ## Think like a scientist - Use a teacher-operated ultrasonic distance sensor to compare echo return times for a target at different measured distances. - **Comparison:** the target distance. **Outcome:** the echo round-trip time. - **Control:** keep the medium and temperature approximately constant. Explain why this makes the comparison fairer. - **Evidence:** Use a consistent method, repeated observations where appropriate and a table with labelled quantities and units. Keep unexpected results and investigate their cause. - **Safety:** Practical activities need teacher supervision and an appropriate risk assessment. Use the provided data or simulation where the investigation specifies it. - **Inquiry task:** State a testable question, predict the outcome using the science, then explain how your observations would support or challenge the prediction. ## Evaluate the science - Ultrasound supports distance measurement and imaging. - Changing temperature, target angle or reflective surface can affect the measurement; a missing echo does not prove the target is absent. - **Evaluation task:** Link your conclusion to evidence, identify a limitation and suggest a specific improvement. Distinguish a measured result from an explanation of its cause.

Ultrasound Uses: Define ultrasound and describe its applications in medicine, sonar, and non-destructive testing.
Pitch, Loudness & Echoes: Relate pitch to frequency, loudness to amplitude, and calculate distances using echoes.
Sound Wave Properties: Describe sound as a longitudinal wave requiring a medium, and explain compressions and rarefactions.
Speed of Sound Measurement: Describe and evaluate methods to measure the speed of sound in air, including using a stopwatch and oscilloscope.
Designing scientific inquiries: Plan a fair comparison: Use a teacher-operated ultrasonic distance sensor to compare echo return times for a target at different measured distances.
Evaluating evidence and impacts: Ultrasound supports distance measurement and imaging. Changing temperature, target angle or reflective surface can affect the measurement; a missing echo does not prove the target is absent.
Sound Waves: Sound waves are **longitudinal** waves produced by vibrating sources.
Measuring the Speed of Sound: Speed of sound in air: **330–350 m/s** (increases with temperature).
Effects of Sound Waves: **Pitch** depends on **frequency**: high frequency → high pitch; low frequency → low pitch.
Ultrasound: **Ultrasound** is sound with frequency **above 20 kHz**.
longitudinal: Sound waves are **longitudinal** waves produced by vibrating sources.
medium: They require a **medium** (solid, liquid, gas) to travel; cannot travel through a vacuum.
compressions: Longitudinal waves consist of **compressions** (regions of higher density) and **rarefactions** (regions of lower density).
rarefactions: Longitudinal waves consist of **compressions** (regions of higher density) and **rarefactions** (regions of lower density).
pressure wave: Sound is a **pressure wave**; compressions and rarefactions cause pressure variations.
330–350 m/s: Speed of sound in air: **330–350 m/s** (increases with temperature).

Kartu flash

Which of the following frequency ranges is completely audible by a human with average hearing?

50 Hz to 5 kHz The human hearing range is approximately 20 Hz to 20 000 Hz. Only the range 50 Hz to 5 kHz lies completely within this range.

A tuba player plays a loud note on her tuba. She then plays a quiet note of the same pitch. Which property of the sound wave she produced has changed?

Amplitude Loudness is related to amplitude. A quiet note has a smaller amplitude but the same frequency (pitch) and wavelength (since speed and frequency are unchanged).

A high frequency note is played on a violin. The violinist then reduces the frequency of the note. What change in the note do the audience hear?

Pitch decreases Pitch is determined by frequency: higher frequency gives higher pitch. Reducing frequency lowers the pitch.

Sound wave W has amplitude A and frequency f. Sound wave X is louder and lower in pitch than sound wave W. What can be said about the amplitude and frequency of sound wave X?

Amplitude higher than A, frequency lower than f Louder means larger amplitude; lower pitch means lower frequency. So amplitude > A and frequency < f.

Which of the following is not a use of ultrasound?

Identifying broken bones Ultrasound is used for fetal scanning, non-destructive testing, and sonar. X-rays are typically used to identify broken bones, not ultrasound.

When objects vibrate, they produce sound waves. An object in a room vibrates. However, a person in that same room does not hear anything. Why not?

The frequency of the sound waves is too great. The human ear can only hear frequencies between about 20 Hz and 20 000 Hz. If the frequency is too high (ultrasound) or too low (infrasound), the sound is inaudible.

After a lockdown drill, the management notes the siren is too quiet and its pitch is too low. They ask the company to make the alarm louder and give it a higher pitch. What effect does this have on the resulting sound wave?

It has a larger frequency and a larger amplitude. Louder means larger amplitude; higher pitch means higher frequency. So both amplitude and frequency increase.

A teacher uses a signal generator connected to a speaker to make sounds of different frequencies. Which frequency can be heard by a student?

440 Hz Human hearing range is roughly 20 Hz to 20 000 Hz. 440 Hz is within this range; 10 Hz is too low, 30 kHz and 120 kHz are too high.

In physics, which wave property causes an echo?

Reflection An echo is the reflection of a sound wave off a hard surface.

A student stands 60 m from a wall. Sound travels at 300 m/s. How long after a clap does the echo return?

0.40 s Sound travels to the wall and back, a distance of 120 m. Time = 120 / 300 = 0.40 s.

A pulse of sound is produced at the bottom of a boat. The sound travels through water, reflects from the sea bed, and returns after 1.3 s. The sea bed is 1000 m below the boat. What is the speed of sound in water?

1500 m/s Total distance travelled = 2 × 1000 = 2000 m. Speed = distance / time = 2000 / 1.3 ≈ 1538 m/s, so about 1500 m/s.

A student stands at a distance d from a wall. He claps his hands and hears an echo 1.2 s later. What is the approximate value of d? (Speed of sound = 340 m/s)

200 m Total distance travelled = 2d = speed × time = 340 × 1.2 = 408 m. So d = 408/2 = 204 m ≈ 200 m.

A student claps her hands 170 m from a tall building. She hears the echo 1.0 s later. What is the speed of sound in air?

340 m/s The sound travels to the building and back, total distance = 2 × 170 = 340 m. Time = 1.0 s. Speed = distance / time = 340 / 1.0 = 340 m/s.

A boat uses sonar to detect a submarine. The sonar emits a pulse of sound and receives the echo 0.48 s later. The speed of sound in water is 1500 m/s. How far is the submarine from the boat?

360 m Total distance travelled = speed × time = 1500 × 0.48 = 720 m. This is twice the distance to the shoal, so distance = 720 / 2 = 360 m.

An ultrasound pulse is sent into a steel bolt to check for internal cracks. The oscilloscope trace shows a pulse reflected from a crack 5 divisions after the initial pulse. Each division represents 0.000002 s. The speed of sound in steel is 6000 m/s. What is the distance from the head of the bolt to the crack?

3 cm Time = 5 × 0.000002 = 0.00001 s. Total distance = 6000 × 0.00001 = 0.06 m = 6 cm. This is twice the distance to the crack, so distance = 3 cm.

A student uses two microphones connected to an oscilloscope to measure the speed of sound. The microphones are placed 2.0 m apart. A clap is made near the first microphone. The oscilloscope shows that the sound reaches the second microphone 0.0059 s later. What is the speed of sound?

339 m/s Speed = distance / time = 2.0 / 0.0059 ≈ 339 m/s. The closest value is 339 m/s.

How would you design the inquiry for sound, ultrasound and measurement?

Use a teacher-operated ultrasonic distance sensor to compare echo return times for a target at different measured distances. Compare the target distance; record the echo round-trip time; keep the medium and temperature approximately constant.

What limitation matters when applying sound, ultrasound and measurement?

Changing temperature, target angle or reflective surface can affect the measurement; a missing echo does not prove the target is absent.

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