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Physics Unit 4 - Capacitors Help!!! Watch

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    Hey guys. Studying for the paper tomorrow. Can you help me with this question?
    Name:  phy.PNG
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    How is D the answer?
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    (Original post by Sandy_Vega30)
    Hey guys. Studying for the paper tomorrow. Can you help me with this question?
    Name:  phy.PNG
Views: 80
Size:  14.7 KB
    How is D the answer?
    You have to use the formula Qx 0.5 = Q x e blah blah
    I tried sending the answer in a picture but it doesnt let me
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    Hi. If you use the equation Q = Q0 x E ^-t/RC and rearrange you can get D as the answer. i've attached the working I did:Name:  Capacitor Working.jpg
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    Hope this helps! If you're unsure about any bit feel free to ask!
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    (Original post by VeeDubSpecs)
    Hi. If you use the equation Q = Q0 x E ^-t/RC and rearrange you can get D as the answer. i've attached the working I did:Name:  Capacitor Working.jpg
Views: 73
Size:  36.9 KB
    Hope this helps! If you're unsure about any bit feel free to ask!
    or remember the answer is referring to half life of the capacitor kinda thing which is 69% so 5x69% gives you 3.45 which is 3.5 (2sf).
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    (Original post by raman_17)
    or remember the answer is referring to half life of the capacitor kinda thing which is 69% so 5x69% gives you 3.45 which is 3.5 (2sf).
    That's a good point! Hadn't thought of that
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    (Original post by VeeDubSpecs)
    Hi. If you use the equation Q = Q0 x E ^-t/RC and rearrange you can get D as the answer. i've attached the working I did:Name:  Capacitor Working.jpg
Views: 73
Size:  36.9 KB
    Hope this helps! If you're unsure about any bit feel free to ask!
    Thank You!! Understood!!
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    (Original post by raman_17)
    or remember the answer is referring to half life of the capacitor kinda thing which is 69% so 5x69% gives you 3.45 which is 3.5 (2sf).
    The half life of a capacitor is 69%? And why do you multiply it by the time constant?
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    (Original post by Sandy_Vega30)
    The half life of a capacitor is 69%? And why do you multiply it by the time constant?
    As its referring to "time taken" to reduce to half which is the half life of the capacitor
 
 
 
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