Question

You were driving your car to UTD at a speed of 35 miles per hour. You stopped at the FloydCampbell intersection with the signal light showing red (wavelength = 6.45 × 10–5 cm). After 30 sec, the signal becomes green whose frequency is 5.80 × 1014 s –1 . Which light has higher energy?

Answer 1

Answer:

green light have high energy

Explanation:

We have given the wavelength of the red light $\lambda =6.45\times 10^{-5}cm=6.45\times 10^{-7}m$

Speed of the light $c=3\times 106{8}m/sec$

The energy of the signal is given by $E=h\nu =h\frac{c}{\lambda }=\frac{6.67\times 10^{-34}\times 3\times 10^{8}}{6.45\times 10^{-7}}=3.1023\times 10^{-15}j$

The frequency of the green light is given by:

$f=5.80\times 10^{14}s^{-1}$

So energy $E=h\nu =6.67\times 10^{-34}\times 5.80\times 10^{14}=3.8686\times 10^{-19}j$

So green light have high energy