1). Systems at higher frequencies can carry more information
(data, pictures, channels, etc.) than at lower frequencies.
2). The "dish" antennas used for satellite communication, both on
the ground and on the satellite, have more gain at higher frequencies
than they have at lower ones.
3). Radio waves at frequencies lower than VHF reflect off of the
ionized layers of the atmosphere and return to Earth. They never
get out to where the satellites are.
4). All of the communication spectrum (frequencies) below VHF
were already being used for other services by the time satellite
communication started (in the 1960's).
H = mc∆T
where, H=heat energy
c = SHC
H = 2*921*(40-20)
H = 36840J
H = 36.84KJ
The energy transferred to it is 36.84KJ
Answer:
Number of absent affects the grade
Explanation:
the dependent variable is the grade and the independent variable is the number of absent, since the grade depends of the number of absents.
The wave phenomenon known as "destructive interference".
