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**Finding how high a "winch" can lift a mass before the battery discharges**

**1. Homework Statement**

The EMF of the D cell battery is 1.5 V and the life is about 10 A/hr. 50% of the energy int he winch does actual work and the lifting mass is 50 kg. The winch has a load resistance variable of Rl.

**2. Homework Equations**

Total Power=VI-V^2/Rl

(1.5*10)-10^2/Rl Total power of the system since the question states that the winch's resistance is much greater than the battery's internal resistance. (Thus ignore battery's resistance.)

**3. The Attempt at a Solution**

After finding the total power of the system, I thought that convert the power into work and using mgh to find the max height of winch would work. But at this point, I do not understand how to convert power into work if I do not know the time. Am I to find the height in terms of hours? I've read the book and searched around the internet but the conversion between power and energy is confusing.

Thank You