To enable continuous power even during night, you would need to have a regular 100 Ah, 12 V lead acid battery (you do not use much electricity in your small cottage). Image: Wikimedia Commons, CC BY 2.0 However, you happen to have an old empty well in your backyard and you start to think if you could somehow utilize that. After all, batteries do not last forever and you would like to find a more sustainable solution. Image: Pxhere.com, CC0 Lets imagine that you could rig a gravitational energy storage by hanging a suitable weight on a cable and linking this cable to a motor-generator: if surplus electricity is available, the motor would lift the weight upwards in the well. Then, when electricity is needed, the weight would drop downwards and rotate the generator to produce electricity. Assumptions: The available well depth is 10 m, i.e. the maximum height difference you can use for the gravitational energy storage is 10 m. You can neglect all energy losses, friction, weight of the cable and other small stuff. We are solving an ideal case. Moreover, the size of the weight does not affect the effective depth. You have always that 10 m available depth regardless of the weight. How large of a weight is needed to store energy content equivalent to the 100 Ah battery? Give the answer in kilograms (kg) without units, rounding to nearest integer (no decimal).
To enable continuous power even during night, you would need to have a regular 100 Ah, 12 V lead acid battery (you do not use much electricity in your small cottage).
Image: Wikimedia Commons, CC BY 2.0
However, you happen to have an old empty well in your backyard and you start to think if you could somehow utilize that. After all, batteries do not last forever and you would like to find a more sustainable solution.
Image: Pxhere.com, CC0
Lets imagine that you could rig a gravitational energy storage by hanging a suitable weight on a cable and linking this cable to a motor-generator: if surplus electricity is available, the motor would lift the weight upwards in the well. Then, when electricity is needed, the weight would drop downwards and rotate the generator to produce electricity.
Assumptions:
- The available well depth is 10 m, i.e. the maximum height difference you can use for the gravitational energy storage is 10 m.
- You can neglect all energy losses, friction, weight of the cable and other small stuff. We are solving an ideal case.
- Moreover, the size of the weight does not affect the effective depth. You have always that 10 m available depth regardless of the weight.
How large of a weight is needed to store energy content equivalent to the 100 Ah battery? Give the answer in kilograms (kg) without units, rounding to nearest integer (no decimal).
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