Asatellite in geostationary orbit is used to transmit data via electromagnetic radiation. the satellite is at a height of 35,000 km above the surface of the earth, and we assume it has an isotropic power output of 1.0 kw (although, in practice, satellite antennas transmit signals that are less powerful but more directional). reception devices pick up the variation in the electric field vector of the electromagnetic wave sent out by the satellite. given the satellite specifications listed in the problem introduction, what is the amplitude e0 of the electric field vector of the satellite broadcast as measured at the surface of the earth? use ϵ0=8.85×10^−12c/(v⋅m) for the permittivity of space and c=3.00×10^8m/s for the speed of light.

Explanation:

P = Power Output = 1000 W

r = Radius = 35000000 m

= Permittivity of free space =

c = Speed of light =

Intensity of Electric radiation

Intensity of Electric radiation

The amplitude of the electric field vector is

12000j is work done

the minimum constant speed at which she can catch the train is 2.7 m/s

given:

acceleration = 0.6

time = 4.5 s

to find:

velocity = ?

formula used:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

solution:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

v = 0 + (0.6 × 4.5)

v = 2.7 m/s

the minimum constant speed at which she can catch the train is 2.7 m/s