An 11,000-watt radio station transmits at 880 khz. calculate the energy of a single photon at the transmitted frequency.
j/photon
5.8 x 10-28
5.8 x 10-31
7.5 x 10-40
7.5 x 10-37

The energy of a single photon at the transmitted frequency is

Option b

Solution:

Energy of photon is given as

Where  c is the velocity of Light

h is planck's constant  

λ is the wavelength of photon  

Energy of photon can be rewritten as

Where f is the frequency of photon  

Frequency of photon is obtained by dividing velocity of light by wavelength of photon.

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.