Question

A light wave from a star has a frequency of 6.67 * 100 Hz and a wavelength of 4.50 x 10 to the power of -7 m.
The star is 4.00 * 10 to the power of 16 m away from Earth.
Calculate the time it takes light from the star to reach the Earth.

Answer 1

Answer:

speed =wavelenght x frequency

v=4.5 x 10 to the -7 x 667=0.3 x 10 to the -4 m/s

speed= distance/time

time=distance/speed

t=4 x 10 to the 16/0.3 x 10 to the -4=13.33 x 10 to the 20 seconds

Explanation: