Wave speed = (wavelength) x (frequency)
Wavelength = (wave speed) / (frequency)
Wavelength = (9 m/s) / (0.5 Hz)
<em>Wavelength = 18 m</em>
No they don't. Incident rays parallel to the axis of a concave mirror
reflect from the mirror's surface and converge at its focal point.
Wind<span> power
holds great promise for the united states because of the great wind power (capacity),
and experts believe wind energy could meet as much as 20 percent of the
nation’s energy needs
. Texas is the state with most wind capacity. On the second place is Iowa and oh the third place Oklahoma. The wind farms produce clean energy that does not harm the environment.</span>
Answer:
1497×10⁵ km
Explanation:
Speed of light in vacuum = 3×10⁵ km/s
Time taken by the light of the Sun to reach the Earth = 8 min and 19 s
Converting to seconds we get
8×60+19 = 499 seconds
Distance = Speed × Time

1 AU = 1497×10⁵ km
The Sun is 1497×10⁵ km from Earth
The centripetal force needed to keep earth in orbit is gravity.