Answer:
he maximum frequency occurs when the denominator is minimum
f’= f₀
Explanation:
This is a doppler effect exercise, where the sound source is moving
f = fo when the source moves towards the observer
f ’=f_o Alexandrian source of the observer
the maximum frequency occurs when the denominator is minimum, for both it is the point of maximum approach of the two objects
f’= f₀
Answer:
The magnitude of the force is 0.7255kN
Explanation:
The elevator floor acts on the person with a force that is due to the gravitational acceleration less the downward acceleration of the elevator:
(force of floor F) = (mass of person m) x [ (grav. acceleration g) - (elevator acceleration a) ]
in other words, considering the elevator floor as a reference frame in the Earth's gravitational field, the person's weight decreases due to the downward acceleration, as follows:
We are given the person's weight at rest, 0.9kN, from which the mass can be determined as:
So