Help with my physics homework please

[madman555]

Homework Statement

How long would it take a radio wave whose frequency is 7.25 x 10^5 Hz to travel from Mars to Earth if the distance between the two planets is approximately 8.00 x 10^7 km.

Homework Equations

Don't know what to put here.

The Attempt at a Solution

7.25 x 10^5 / 8.00 10^9=9.0625 x 10^-5
Is that they right answer or am i doing this whole thing the wrong way?

 

[berkeman]

Homework Statement

How long would it take a radio wave whose frequency is 7.25 x 10^5 Hz to travel from Mars to Earth if the distance between the two planets is approximately 8.00 x 10^7 km.

Homework Equations

Don't know what to put here.

The Attempt at a Solution

7.25 x 10^5 / 8.00 10^9=9.0625 x 10^-5
Is that they right answer or am i doing this whole thing the wrong way?

Hint: The frequency of the radio wave is irrelevant in this question. What is the velocity of propagation of light (and hence radio waves) in a vacuum?

 

[thomate1]

Hello,

Thank you for reaching out for help with your physics homework. I can assist you in solving this problem.

The equation that you need to use for this problem is the speed of light equation, which is c = fλ, where c is the speed of light, f is the frequency, and λ is the wavelength. In this case, we are given the frequency, so we can use this equation to find the wavelength of the radio wave.

First, we need to convert the given distance between Mars and Earth from kilometers to meters. This can be done by multiplying 8.00 x 10^7 km by 1000, which gives us 8.00 x 10^10 m.

Next, we need to find the wavelength of the radio wave. We can do this by rearranging the speed of light equation to solve for λ. This gives us λ = c/f.

The speed of light is a constant value of 3.00 x 10^8 m/s. Plugging in the given frequency of 7.25 x 10^5 Hz, we get:

λ = (3.00 x 10^8 m/s) / (7.25 x 10^5 Hz)
λ = 413.79 m

Now that we have the wavelength, we can use the distance formula, d = vt, to find the time it takes for the radio wave to travel from Mars to Earth.

d = vt
8.00 x 10^10 m = (3.00 x 10^8 m/s) * t
t = (8.00 x 10^10 m) / (3.00 x 10^8 m/s)
t = 2.67 x 10^2 s

Therefore, it would take approximately 2.67 x 10^2 seconds for a radio wave with a frequency of 7.25 x 10^5 Hz to travel from Mars to Earth.

I hope this helps you with your homework. Keep up the good work!