Answer:
540m/s
Explanation:
Given parameters:
Frequency of the wave = 18000Hz
Wavelength of the wave = 0.03m
Unknown:
How fast is the wave traveling = ?
Solution:
How fast the wave is traveling is a measure of the speed of the wave;
Speed of wave = frequency x wavelength
Now insert the given parameters and solve;
Speed of wave = 18000 x 0.03 = 540m/s
Answer:
21.9 seconds
Explanation:
lets say the speed of sound at room temp 343m/s and one kilometer is 1000 meters. so 7.5 kilometers is equal to 7500 meters and we divide this number by 343 and we get 21.8 seconds
The centripetal acceleration of the car is 48,800 mi/h2
We have that F=ma from the 2nd Newton law where F is the force, m is the mass and a is the acceleration. Suppose we have that F' is the new force and m' is the new mass. Then, we have that a'=F'/m' still, by rearranging Newton's law. We are given that F'=2F and m'=m/2. Hence,

But now, we have from F=ma, that a=F/m and we are given that a=1m/s^2.
We can substitute thus, a'=4a=4*1m/s^2=4m/s^2.