How devices use waves to send and capture information and energy
Grade 11 Science Worksheet
Circle the best answer, or write your answer on the line.
An ultrasound pulse returns from a boundary in a gel test block after 130 μs. The scanner assumes 1540 m/s. How deep is the boundary, to 0.01 cm, Ari?
An ultrasound pulse returns from a boundary in a gel test block after 78 μs. The scanner assumes 1540 m/s. How deep is the boundary, to 0.01 cm, Bo?
An ultrasound pulse returns from a boundary in a gel test block after 200 μs. The scanner assumes 1540 m/s. How deep is the boundary, to 0.01 cm, Esme?
Read this first
Use this
The scanner assumes sound travels 1540 m/s.
In the signal strip, about how deep is the boundary whose echo returns after 52 μs, Jun?
- About 8 cm
- About 52 cm
- About 4 cm
In the signal strip, why does one echo arrive later than the other, Kira?
Use the picture in question 4.
- It came from deeper down
- It traveled faster
- It was a much louder echo
In the signal strip, why does the scanner halve each echo time, Luz?
Use the picture in question 4.
- Half the echo is lost
- Sound slows down by half in the gel
- The pulse goes down and back
Panels are rated at 1000 W/m² of sunlight (NREL test conditions). A 1.6 m² panel is 20% efficient. What power does it give, Milo?
- 1600 W
- 200 W
- 320 W
A second panel has twice the area and the same efficiency. How does its power compare, Noah?
- Half as much
- Four times as much
- Twice as much
Why do phones use radio waves rather than visible light to reach a tower, Ren?
- Radio passes through walls
- Light can't carry bits
- Radio is faster than light
Why does a digital call stay clear even with a little noise, Zee?
- The phone turns the noise up
- Bits are read as 0 or 1
- Noise can't reach radio waves