Two of the three tuning forks have known frequencies. When a 510 Hz. fork and the unknown fork are struck together, four beats p
er second are heard. When a 505 Hz. fork is struck with the unknown fork, beats are produced that are too numerous to count accurately. What is the frequency of the unknown fork?
4 Hz is the difference between 510 and the unknown. <span>Therefore the unknown is either 514 or 506. </span>
<span>If 505 and 506 were struck together, the diff would be 1 Hz </span> <span>If 505 and 514 were struck toghether, the diff would be 9 Hz which would be difficult to count accurately, </span>
All of the frictions are the same, but weight always goes straight down so it can only be A or B. Since they are going down a slope, then the normal force must be sloped. A is the only one out of A and B with a sloped normal force, so it has to be A
