Electromagnetic waves emitted by an omnidirectional broadcast antenna on earth strike a 4.23-m^2 flat surface that forms part of an artificial satellite that is located 251 km from the antenna. the surface is oriented perpendicular to the propagation direction of the waves and acts as a perfect reflector. what power output in gigawatts would be required from the antenna in order to acheive a radiation force of 1.87n on the surface?

   P = 0.42 GW

Explanation:

For this in exercise let's calculate the intensity of radiation on the antenna, for this we use the expression of the radiation pressure on a reflective surface

      P = 2 I / c

The definition of pressure is

      P = F / A

      F / A = 2 I / c

      I = F c / 2 A

Let's calculate

      I = 1.87 3 10⁸ / (2 4.23)

      I = 0.993 10⁸ W / m²

This is the intensity over the satellite antenna

The definition of intensity

      I = P / A

The emitted power is

      P = I A

      P = 0.993 10⁸  4.23

      P = 4.2 10⁸ W

      P = 0.42 GW

spare some change and give it to the poor

explanation:

plz : ((

weight of the box is given as

here this is placed on the inclined of angle 42 degree

now this weight will have two components one is along the incline other is perpendicular to it

so here we need to apply a force parallel to incline opposite to its component of weight

so here the component of weight is given as

here we have

so it requires 75 n force to move it upwards