Question 18N.2.HL.TZ0.4c.i
| Date | November 2018 | Marks available | [Maximum mark: 1] | Reference code | 18N.2.HL.TZ0.4c.i |
| Level | HL | Paper | 2 | Time zone | TZ0 |
| Command term | Demonstrate | Question number | c.i | Adapted from | N/A |
A pipe is open at both ends. A first-harmonic standing wave is set up in the pipe. The diagram shows the variation of displacement of air molecules in the pipe with distance along the pipe at time t = 0. The frequency of the first harmonic is f.
A transmitter of electromagnetic waves is next to a long straight vertical wall that acts as a plane mirror to the waves. An observer on a boat detects the waves both directly and as an image from the other side of the wall. The diagram shows one ray from the transmitter reflected at the wall and the position of the image.
Demonstrate, using a second ray, that the image appears to come from the position indicated.
[1]
construction showing formation of image ✔
Another straight line/ray from image through the wall with line/ray from intersection at wall back to transmitter. Reflected ray must intersect boat.