How does high internal resistance make high voltage power supplies safe?

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SUMMARY

High internal resistance in voltage power supplies ensures safety by limiting the terminal potential difference and current output. When the internal resistance is significantly larger than the external resistance, the terminal voltage (Vterminal) decreases, preventing excessive current flow. This principle is crucial for laboratory settings where high voltage supplies are used, as it mitigates the risk of electric shock and equipment damage.

PREREQUISITES
  • Understanding of Ohm's Law
  • Familiarity with the concept of internal resistance
  • Knowledge of electromotive force (EMF)
  • Basic principles of electrical circuits
NEXT STEPS
  • Research the effects of internal resistance on circuit performance
  • Study the design principles of high voltage power supplies
  • Learn about safety protocols for laboratory electrical equipment
  • Explore the relationship between voltage, current, and resistance in practical applications
USEFUL FOR

Electrical engineers, laboratory technicians, and safety officers involved in the design and operation of high voltage power supplies.

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Homework Statement


When the internal resistance is large in comparison to the external resistance, the terminal potential difference falls to a small value. This is used to make high voltage supplies safe for use in a laboratory. Explain how this makes the supply safe.

Homework Equations


Vterminal = EMF - Vinternal

The Attempt at a Solution


If the internal resistance is high, since Vinternal = I r, where r is the internal resistance, the Vinternal will be high. This means the Vterminal will be low. And because of the internal resistance, the current will also be low. So then what is the point of having a high voltage power supply?
 
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I have attached what I think is the solution. Please could you look at it and see if it makes sense and is right. Thanks
 

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