<span>Frequency x Wavelength = Speed of light
Now, speed of light = 3 x 10^5 km/s = 3 x 10^8 m/s = 3 x 10^10 cm/s
Frequency = speed/Wavelength
= (3 x 10^10)/(4.257 x 10^-7)
=7 x 10^16 Hz</span>
Answer:
I answered Number 4 (Solids and Elasticity)
Explanation:
solids and elasticity
A wind turbine turns wind energy into electricity using the aerodynamic force
D is the answer
Velocity maybe negative or positive
while speed is always positive
