1a)What frequency pulse does the family in the nest detect?f' = __kHz
1b)What frequency pulse does the swiftlet detect reflected from the nest?f" =__kHz
1c)On detecting the pulse the parent waiting in the nest realises that it is its turn to leave to find food. It flies towards the approaching swiftlet with a speed of 12.7 m/s. What frequency pulse does the swiftlet leaving the nest now detect coming from the swiftlet approaching the nest? f' =__ kHz
1d)What frequency pulse does the swiftlet approaching the nest detect reflected of the swiftlet leaving the nest? f" = __kHz
Q2 The body of a car is suspended on four identical springs. Consider a car with a mass of 1475 kg. This mass is evenly distributed over the four springs. These springs cause the car to oscillate with a frequency of 2.51 Hz when empty.
2a) What is the spring constant of these springs?__ N/m
2b)Five large people, each with a mass of 111 kg climb into the car. What distance does the suspension of the car drop? __cm
2c) What frequency does the car oscillate with now? __Hz
更新1:
~~~Please help~~~thank you~~~
更新2:
謝謝~~ 不過我交了first draft 有兩題答案不對 1d)What frequency pulse does the swiftlet approaching the nest detect reflected of the swiftlet leaving the nest? f" = __kHz 2b)Five large people, each with a mass of 111 kg climb into the car. What distance does the suspension of the car drop? __cm 會有別的想法嗎？