# discrete signals

Discussion in 'Homework Help' started by bhuvanesh, Feb 16, 2015.

1. ### bhuvanesh Thread Starter Member

Aug 10, 2013
268
2
my professor said that everything in nature is on continuous time domain (continuous signal) and there is no discrete signals. i too know that do you have any idea that why discrete signal are not in nature .i am expecting geeky answers about this.Thank you

2. ### WBahn Moderator

Mar 31, 2012
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Your professor is wrong -- but only in the fine print. Some things in nature are inherently discrete (quantized). How much charge an object has is an integer multiple of the charge on an electron (subatomic particles notwithstanding, which are still quantized). But on a macro scale, the quantization of things is so fine that it might as well be continuous. Other things are inherently continuous, such as distance or time (although some physical theories postulate quanta for these, too).

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3. ### MrChips Moderator

Oct 2, 2009
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Your professor is right and wrong.

I made the statement in another thread that all digital signals are analog.
What both your professor and I are referring to are electrical signals such as current or voltage.

Of course you can find many things in nature that are discrete.

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4. ### bhuvanesh Thread Starter Member

Aug 10, 2013
268
2

could some give me example for discrete signals and digital signals?

Apr 5, 2008
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6. ### MrChips Moderator

Oct 2, 2009
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Any kind of detector than detects the presence of particles such as alpha, beta, gamma rays or photons will produce a discrete signal.

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Oct 2, 2009
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8. ### bhuvanesh Thread Starter Member

Aug 10, 2013
268
2
@bertus
This is one of reply to the question i am just quoting the lines from the above paragraph that i feel wrong

quantisation can only be done after sampling,right?

he is saying in reverse,what i feel right is all digital signals are discrete signal ,is that right?