Calculating Electromagnetic Energy from Satellite Dish

[ilovephysics2]

Homework Statement

A typical electromagnetic signal from a communications satellite might have an intensity of 0.9 pW/m2 at the surface of the Earth. Your satellite dish collects the energy of the electromagnetic signal from the satellite; then your dish passes that energy to its central receiver, where the signal can be processed by a circuit. The area of a satellite dish can be calculated from pi (3.1416) times the radius squared. If your satellite dish has a radius of 0.36 m, and if it is receiving the signal described above, how much electromagnetic energy is reflected to the central receiver in 2.5 minutes? Express in pj and MeV

Homework Equations

The Attempt at a Solution

I tried solving this but I am not sure what equation to use.

 

[Mentallic]

How about energy=power*time?

Total power input = power of signal * area

sorry that I don't know the actual proper formulas, I'm just using common sense here.

 

[thomate1]

Can you please provide the necessary equations?

There are a few equations that can be used to calculate the electromagnetic energy from a satellite dish:

1. Intensity (I) = Power (P) / Area (A)
This equation relates the intensity of the electromagnetic signal to the power and area of the satellite dish. In this case, the intensity is given as 0.9 pW/m2, and the area of the satellite dish can be calculated using the given radius (0.36 m). Therefore, we can rearrange the equation to solve for power:
Power (P) = Intensity (I) * Area (A)

2. Power (P) = Energy (E) / Time (t)
This equation relates power to energy and time. In this case, we are given the time (2.5 minutes) and we need to calculate the energy that is reflected to the central receiver. Therefore, we can rearrange the equation to solve for energy:
Energy (E) = Power (P) * Time (t)

3. Energy (E) = Mass (m) * (Speed of light)^2
This equation is known as Einstein's famous equation, E=mc^2, and it relates energy to mass. In this case, we can calculate the mass of the electromagnetic energy using the energy calculated in equation 2 and the speed of light (3 x 10^8 m/s).

Using these equations, we can calculate the electromagnetic energy from the satellite dish:

Step 1: Calculate the area of the satellite dish
Area (A) = pi * (radius)^2 = 3.1416 * (0.36 m)^2 = 0.4071 m^2

Step 2: Calculate the power of the electromagnetic signal
Power (P) = Intensity (I) * Area (A) = 0.9 pW/m2 * 0.4071 m^2 = 0.3664 pW

Step 3: Calculate the energy reflected to the central receiver
Energy (E) = Power (P) * Time (t) = 0.3664 pW * 2.5 minutes = 0.916 pJ

Step 4: Convert to MeV
To convert from pJ to MeV, we can use the fact that 1 MeV is equal to 1.602 x 10^-13 Joules. Therefore:
Energy