What number on a digital clock draws the least current from a battery?

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The discussion focuses on determining which number on a digital clock draws the least current from a battery when represented by LEDs. It is established that each number corresponds to a certain number of lit LEDs, with the number 1 lighting only 2 LEDs, while other numbers light more. The consensus is that the number 1, which has the most switches open, draws the least current due to the higher resistance created by the open switches. The initial confusion about resistance and current is clarified, leading to the conclusion that displaying the number 1 is optimal for minimal current draw. The thread concludes with the question being resolved satisfactorily.
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Homework Statement


There is a circuit with 7 LEDS connected in parallel, each with a switch on its parallel. There is a battery supplied.

The LEDS correspond to those of a digital clock for example the number 8 would light up all 7 LEDS, whilst the number 0 would light up 6 LEDS.

Which number from 0 to 9 draws the least current from the battery (For example to light up 3 I would have to close 5 switches)

Homework Equations



V=IR

The Attempt at a Solution



I'm slightly confused. Since the voltage is remaining the same, the only thing that would make the resistance decrease would be the resistance. I think (please correct me if I am wrong) that an open switch causes infinite resistance, therefore the number with the most open switches would cause the least current, number 1 as 5 LEDS are off

Any idea would be helpful, thanks
 
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I agree that displaying 1 draws the least current.
 
Thank you very much, question is answered, this thread is now obsolete.
 
Thread 'Variable mass system : water sprayed into a moving container'

Thread 'Variable mass system : water sprayed into a moving container'

Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
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