How Do Hand Crank Power Devices Work?

In summary: Thanks for taking the time to write it all out. In summary, these devices use a small generator to produce a high voltage and current which can be used for a variety of purposes, such as charging a capacitor or battery, powering a phone, or killing someone.
  • #1
philipc
57
0
I've seen them on radios, cell phone charges and flashlights. I haven't seen one in person, but I just want to get an idea of how they work. I'm guessing some massive gearing and a small generator/motor? And what does it use to store the energy? Or is it stored mechanical energy?
Thanks
Philip
 
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  • #2
Hello,
You are correct about some gearing and a small generator. These devices can be made to utilize the hand power in different ways. I’ve seen little flashlights and radios sold to the general public that use the generator to charge a capacitor or battery. The field telephones that I’ve had for many years (circa 1952) use two D-cell batteries to send the voice signals over the wires, and the hand crank is used for ringing the bell of the phone you’re calling. What is produced is a small current and about and around 90 volts ac (when cranked swiftly). After cranking, you flip a lever on the handset to energize the system from the batteries.
 
  • #3
Thanks for the insight.
By the way, to kill two birds with one stone, I will make this comment here.
Also thanks for the info on the transformer, sorry for calling you Terry, my mistake.
For my part box, I've been collecting everyone's old stuff for the last year, so I'm up to about 20+ transformers in my collection. It is such a shame that I threw all that stuff in the past. I use to take everything apart as a kid, but didn't know jack from didely, so I threw everything away. I would have to say it's much more fun taking the stuff apart now that I've had physics II :) Can't wait for the more serious classes.
Philip
 
  • #4
As a "lesson," our junior high shop teacher would have one of us hold onto a field generator's leads while another one cranked it. Needless to say, we let go of the wires ASAP! That 50 volts, I found out later, is enough to kill you. [b(]
 
  • #5
Originally posted by Loren Booda
As a "lesson," our junior high shop teacher would have one of us hold onto a field generator's leads while another one cranked it. Needless to say, we let go of the wires ASAP! That 50 volts, I found out later, is enough to kill you.

Actually, getting killed by electricity is a bit wierd. It ultimately depends not only on the voltage and current, but also on the frequency.
 
  • #6
I guess you are referring to the body's reactance? Also, one frequency may, e. g., reinforce the heart, whereas another may cause it to defibrillate.
 
  • #7
Actually, the frequency determines where the current flows. High frequency electricity is primarily conducted by the skin and is less likely to cause problems or causes different problems.

The range of currents that cause fibrilation is relatively small, and higher currents will simply cause the entire heart to contract at once - resetting it. (Fibrilation is when the heart doesn't contract cohesively so it ceases pumping blood. Defibriliation usually refers to the application of current to try to reset or restart a heart that is fibrilating, or has stopped beating.)
 
  • #8
A good lesson, Nate!
 

1. How does a hand crank power device generate electricity?

A hand crank power device works by converting mechanical energy into electrical energy. When the crank is turned, it causes a series of gears and pulleys to rotate, which in turn rotates a magnet inside a coil of wire. This movement of the magnet creates an electromagnetic field, which induces a current in the wire, generating electricity.

2. What are the main components of a hand crank power device?

The main components of a hand crank power device include a crank, gears, pulleys, a magnet, and a coil of wire. Some devices may also have a voltage regulator, a battery, and a power outlet for easy use and storage of the generated electricity.

3. How much electricity can a hand crank power device generate?

The amount of electricity a hand crank power device can generate depends on its design and the amount of force applied to the crank. On average, these devices can generate enough electricity to power small electronic devices such as radios, flashlights, and cell phones.

4. Are hand crank power devices environmentally friendly?

Yes, hand crank power devices are environmentally friendly as they do not require any fuel or produce any emissions. They also do not rely on non-renewable resources, making them a sustainable and eco-friendly option for generating electricity.

5. How long does it take to charge a device using a hand crank power device?

The time it takes to charge a device using a hand crank power device depends on the size and capacity of the device being charged and the amount of force applied to the crank. On average, it can take anywhere from 30 minutes to a few hours to fully charge a device.

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