PHYSICS: THE FIXATION ON EXAMINATION (GR.10)
By AdresteaJarde
Chapter 1: Current and potential difference.
WORK
Current: Current is a measure of the rate of flow of electric charge in a circuit.
o Electric charge is measured in coulombs. W
o A current of 1A is a/1 coulombs of charge flowing every second.
V Q CHARGE
▪ 1A = 1 C/s
= C.s-1 VOLTS
A 1V cell gives 1 joule (J) of energy to each coulomb of charge.
o Cell: A useful source of energy.
▪ A chemical reaction takes place inside the cell, and it produces potential difference (V)
▪ Fun Fact: Magnesium Oxide (MgO) can be found within a cell.
o Battery: Consists of 2+ cells that are joined together.
▪ The potential difference (in a battery) is the sum of potential differences across cells. Eg.
|I|I|I; Each cell has a potential difference (V) of 1.5V. To calculate the potential difference we have to
add the potential differences all together. Therefore, 1.5V*3 = 4.5V.
Fact: Voltage is another word for potential difference.
Measurements and Units of Measurement
o Voltmeter – Measures potential difference (V).
▪ Unit: Volts.
▪ Connection: Parallel
▪ High internal Resistance.
o Ammeter – Measures Current (I).
▪ Unit: Amperes
▪ Connection: Series
▪ Low internal resistance. |I
Fact: Currents always pass along the path of least resistance.
o Short Circuits: A current flowing along a path without passing through
the components. Eg.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller AdresteaJarde. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $5.89. You're not tied to anything after your purchase.