Answer:
a) Wavelength of the ultrasound wave = 0.0143 m <<< 3.5m, hence its ability is not limited by the ultrasound's wavelength.
b) Minimum time difference between the oscillations = Period of oscillation = 0.00952 ms
Explanation:
The frequency of the ultrasound wave = 105 KHz = 105000 Hz. The speed of ultrasound waves in water ≈ 1500 m/s. Wavelength = ?
v = fλ
λ = v/f = 1500/105000 = 0.0143 m <<< 3.5m
This value, 0.0143m is way less than the 3.5m presented in the question, hence, this ability is not limited by the ultrasound's wavelength.
b) Minimum time difference between the oscillations = The period of oscillation = 1/f = 1/105000 = 0.00000952s = 0.00952 ms
Hope this helps!
FOUR USES OF CONCAVE MIRROR:Satellite dishes,headlights of a car, telescopes used for astronomical studies, and shaving mirrors because of there curved and reflective surface.
FIVE USES OF LENSES: Camera lens ,microscopes ,magnifying glass,eyeglasses,projector
Well, st first we should find <span>initial momentum for the first person represented in the task which definitely must be :
</span>
![(65+0.045)*2.5](https://tex.z-dn.net/?f=%2865%2B0.045%29%2A2.5)
And then we find the final one :
![65*x + 0.045*30](https://tex.z-dn.net/?f=65%2Ax%20%2B%200.045%2A30)
Then equate them together :
So we can get the velocity, which is
![is 2.48 m/s](https://tex.z-dn.net/?f=%20is%202.48%20m%2Fs)
In that way, according to the main rules of <span>conservation of momentum you can easily find the solution for the second person.
Regards!</span>
I belive its like 1200 mile per hour ive done he math for it