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AS physics, recent question on power and resistance, cannot understand?

Peter Check

Peter Check

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Another question, if I may ask: In a graph what shows the random nature of a radioactive particle?, the fluctuation or its decreasing gradient??
 
arlery

arlery

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Peter Check said:
both.
Click to expand...
Well for d (i) Since P =V^2/R
and R = 0 therefore, P =0

as for d (ii) if the resistance is infinite then P =V^2/ infinity
and the answer of anything divided by infinity is zero. Hence the power will still be 0.
 
Peter Check

Peter Check

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okay
arlery said:
Well for d (i) Since P =V^2/R
and R = 0 therefore, P =0

as for d (ii) if the resistance is infinite then P =V^2/ infinity
and the answer of anything divided by infinity is zero. Hence the power will still be 0.
Click to expand...
okay, the second part makes sense, but for the first part if, R=0, wont P be undefined(you cannot have a denominator as 0)?
 
arlery

arlery

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Peter Check said:
okay
okay, the second part makes sense, but for the first part if, R=0, wont P be undefined(you cannot have a denominator as 0)?
Click to expand...
No it's going to be zero because any number divided by zero would be zero.
and if that doesn't make sense then look at it this way, if the variable resistor's resistance is 0 then no voltage will be able to pass through it, hence the Power will be zero since no work is done.
 
Peter Check

Peter Check

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arlery said:
No it's going to be zero because any number divided by zero would be zero.
and if that doesn't make sense then look at it this way, if the variable resistor's resistance is 0 then no voltage will be able to pass through it, hence the Power will be zero since no work is done.
Click to expand...
'Any number divided by zero is NOT zero, its UNDEFINED, at least thats what i knew!' , the second way, was actually my first basis of reasoning when solving, and I couldn't agree more, but dusn't this statement contradict the first answer!
 
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