Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: ap, while the solid copper sheet was stopped between the poles of the magnet. This demonstrates which law? Explain. Lenz’s or Faraday’s Law: The opposing induced current is much bigger in the solid sheet. He slots in the other sheet break up thecurrents, making the opposing field it produces much smaller. 2. A 341 Hz tuning fork excites what wavelength of sound in a column of class room air 25 cm long? Λ=c/f=341/341=1m. I gave the 25 cm which is what you would measure in the lab experiment we did=1/4 λ. You did not need it here. 3. Two tuning forks as in problem #2 are made to oscillate in phase. One is 1.5 m directly in front of you and the other 2.0 m in front of you. What do you hear? Explain, perhaps drawing a picture. The tuning forks send sound from positions ½ λ apart, so they DESTRUCTIVELY interfere, cancelling each other, so that you hear no sound. 4. How far apart are the hot spots when cooking in a microwave oven (no turn table)? Show your calculation. λ/2=c/f=3x108/2450x106=12 cm (λ/2 because that is the distance between maxima in the standing wave). 5. You rub a plastic straw, charging it, and wave it up and down 3 times per second. What is the frequency of E‐M radia...
View Full Document

{[ snackBarMessage ]}

Ask a homework question - tutors are online