Answer:
42 Hz
Explanation:
Given,
Speed ( v ) = 210 m/s
Wavelength ( λ ) = 5 m
To find : Frequency ( f ) = ?
Formula : -
v = f λ
f = v / λ
= 210 / 5
f = 42 Hz
Power = current x voltage
So the power is 7 x 110 = 770 W = 0.77kW
0.77 x 13 = 10.01 kWh
10.01 x 10 cents = 100.1 cents (is this 1 dollar? Idk I use a different currency)
1) Keep track of data
2) be able to clearly analyse the data
I hope this was the answer you seek!
The wavelength would decrease because frequency is inversly proportional to the wavelength provided the speed is constant: f=v/λ