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Satellites may be used to transmit information over large distances.
Global wireless communication relies on satellites. Here,
ground stations transmit to orbiting satellites that amplify thesignal and retransmit it back to earth. Satellites will move
across the sky unless they are in
geosynchronous
orbits , where the time for one revolution about the
equator exactly matches the earth's rotation time of one day.TV satellites would require the homeowner to continually adjust
his or her antenna if the satellite weren't in geosynchronousorbit. Newton's equations applied to orbiting bodies predict
that the time
for one orbit is related to distance from the earth's center
as
where
is the
gravitational constant and
the earth's mass.
Calculations yield
, which corresponds to an altitude of
. This altitude greatly exceeds that of the
ionosphere, requiring satellite transmitters to use frequenciesthat pass through it. Of great importance in satellite
communications is the transmission delay. The time forelectromagnetic fields to propagate to a geosynchronous
satellite and return is 0.24s, a significant delay.
In addition to delay, the propagation attenuation
encountered in satellite communication far exceeds whatoccurs in ionospheric-mirror based communication. Calculate
the attenuation incurred by radiation going to the satellite(one-way loss) with that encountered by Marconi (total going
up and down). Note that the attenuation calculation in theionospheric case, assuming the ionosphere acts like a
perfect mirror, is not a straightforward application of the
propagation
loss formula .
Transmission to the satellite, known as the uplink,
encounters inverse-square law power losses. Reflecting offthe ionosphere not only encounters the same loss, but twice.
Reflection is the same as transmitting exactly what arrives,which means that the total loss is the
product of the uplink and downlink losses. The
geosynchronous orbit lies at an altitude of
. The ionosphere begins at an altitude of about
50km. The amplitude loss in the satellite case is
proportional to
;
for Marconi, it was proportional to
.
Marconi was
very lucky.
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what does preconceived mean
How can I develope my cognitive domain
why is communication effective
Communication is effective because it allows individuals to share ideas, thoughts, and information with others.
effective communication can lead to improved outcomes in various settings, including personal relationships, business environments, and educational settings. By communicating effectively, individuals can negotiate effectively, solve problems collaboratively, and work towards common goals.
it starts up serve and return practice/assessments.it helps find voice talking therapy also assessments through relaxed conversation.
miss
Every time someone flushes a toilet in the apartment building, the person begins to jumb back automatically after hearing the flush, before the water temperature changes. Identify the types of learning, if it is classical conditioning identify the NS, UCS, CS and CR. If it is operant conditioning, identify the type of consequence positive reinforcement, negative reinforcement or punishment
please i need answer
Wekolamo
because it helps many people around the world to understand how to interact with other people and understand them well, for example at work (job).
Agreed 👍 There are many parts of our brains and behaviors, we really need to get to know. Blessings for everyone and happy Sunday!
ARC
A child is a member of community not society elucidate ?
Isn't practices worldwide, be it psychology, be it science. isn't much just a false belief of control over something the mind cannot truly comprehend?
compare and contrast skinner's perspective on personality development on freud
Skinner skipped the whole unconscious phenomenon and rather emphasized on classical conditioning
war
explain how nature and nurture affect the development and later the productivity of an individual.
nature is an hereditary factor while nurture is an environmental factor which constitute an individual personality. so if an individual's parent has a deviant behavior and was also brought up in an deviant environment, observation of the behavior and the inborn trait we make the individual deviant.
Samuel
I am taking this course because I am hoping that I could somehow learn more about my chosen field of interest and due to the fact that being a PsyD really ignites my passion as an individual the more I hope to learn about developing and literally explore the complexity of my critical thinking skills
and having a good philosophy of the world is like a sandwich and a peanut butter 👍
Jonathan
generally amnesi how long yrs memory loss
interpersonal relationships
What would be the best educational aid(s) for gifted kids/savants?
treat them normal, if they want help then give them.
that will make everyone happy
Saurabh
What are the treatment for autism?
hello. autism is a umbrella term. autistic kids have different disorder overlapping. for example. a kid may show symptoms of ADHD and also learning disabilities.
before treatment please make sure the kid doesn't have physical disabilities like hearing..vision..speech problem. sometimes these
Jharna
continue..
sometimes due to these physical problems..the diagnosis may be misdiagnosed.
treatment for autism.
well it depends on the severity.
since autistic kids have problems in communicating and adopting to the environment.. it's best to expose the child in situations where the child
Jharna
child interact with other kids under doc supervision.
play therapy.
speech therapy.
Engaging in different activities that activate most parts of the brain.. like drawing..painting. matching color board game.
string and beads game.
the more you interact with the child the more effective
Jharna
results you'll get..
please consult a therapist to know what suits best on your child.
and last as a parent. I know sometimes it's overwhelming to guide a special kid.
but trust the process and be strong and patient as a parent.
Jharna
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Source:
OpenStax, Fundamentals of electrical engineering i. OpenStax CNX. Aug 06, 2008 Download for free at http://legacy.cnx.org/content/col10040/1.9
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