Chapter 10 Flashcards
What is a model?
A set of assumptions that simplifies and idealises a particular situation.
What makes a nucleus unstable?
Too many or too little neutrons, too many nucleons or too much energy.
Describe what an unstable nuclei does to become stable.
They break down by releasing energy and/or particles until they reach a stable form. This is known as radioactive decay.
What is the decay constant (λ)?
It measures how quickly an isotope will decay. Its the probability of a given nucleus decaying in a certain time.
Activity=
Decay Constant (λ) x Number of Undecayed Nuclei (N)
What is a half-life?
The half-life of an isotope is the average time it takes for the number of undecayed nuclei to halve.
Capactiance=
Q(Charge)/V(Potential Difference)
Current(I)=
Change in Q/Change in t
Energy stored in a capacitor(E)=
1/2QV. (Might be an area under graph question)
How do you discharge a capacitor?
Disconnect the power and close the switch.
How do you know when the capacitor is fully discharged?
When the current through the ammeter and the potential difference across the plates are zero.
What are the two factors that affect the time taken to charge or discharge?
The capacitance of the capacitor and the resistance of the circuit.
What is the relationship between Discharge Rate and Charge Remaining?
Proportional. The amount of charge initially falls quickly but slows as the amount of charge remaining decreases.
