Electromotive Force: Calculate Charge, E.M.F & P.D.

AI Thread Summary
The discussion revolves around calculating various electrical parameters from a given scenario involving an Atorch battery and a bulb. The charge that flows is calculated to be 1100 C using the formula Q=IT. The electromotive force (e.m.f.) of the battery is determined to be 4.73V by dividing the total energy transferred by the charge. To find the potential difference (p.d.) across the bulb, the power dissipated can be calculated by dividing the energy transferred by time, which leads to further calculations for lost volts. The thread emphasizes understanding the relationship between energy, charge, and voltage in electrical systems.
Xazdrubal
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Homework Statement



Atorch battery transfers 5200J of chemical energy into electrical energy while supplying a current of 0.25A for 4400 s. The bulb transfers 4800 j of electrical energy into heat and light during this time. Calculate
a)the charge that flows
b)the e.m.f. of the battery
c) the p.d. across the bulb
d)the lost volts

Homework Equations



Q=IT


The Attempt at a Solution


a) 0.25 x 4400 = 1100 C
b)5200/1100 = 4.73V
C) V=W/Q

NOT SURE WHAT TO DO FOR C / D /
 
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Xazdrubal said:

Homework Statement



Atorch battery transfers 5200J of chemical energy into electrical energy while supplying a current of 0.25A for 4400 s. The bulb transfers 4800 j of electrical energy into heat and light during this time. Calculate
a)the charge that flows
b)the e.m.f. of the battery
c) the p.d. across the bulb
d)the lost volts

Homework Equations



Q=IT


The Attempt at a Solution


a) 0.25 x 4400 = 1100 C
b)5200/1100 = 4.73V
C) V=W/Q

NOT SURE WHAT TO DO FOR C / D /

Welcome to the PF.

What does "p.d. across the bulb" mean? Power dissipated?

If so, then power is just total energy divided by time, right?

Once you have the bulb power, calculate the bulb voltage, and the difference between that and the battery source EMF is what is lost across the battery's internal resistance.
 
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