Mistakes in Practice Papers Flashcards
Direct P.D definition
Polarity of p.d does not change
Half life definition
Time for the activity to half
Why does a shorter half life make an element more dangerous?
“Greater activity”
In a shorter time
How do Electrons move up and down energy levels
- They move up energy levels by taking in EM radiation
- They move down energy levels by emitting EM radiation
Conclusions from a data set
Exam technique
As general as possible (e.g Matt surfaces absorb more radiation than shiny surfaces)
NOT specific (e.g The matt black flask absorbed the most)
Induced Magnet Definition
A material that become a magnet when placed in a magnetic field
Closed system definition
The total energy/momentum remains constant
Red shift questions
More red shift = moving faster AND further away
Errors in ray experiment
- Centres of ray marked incorrectly
- Block (re)placed incorrectly
- Protractore measurement taken incorrectly
Why are iron cores used in electromagnets/transformers
It is EASY to induce a magnetic field around iron
Why is there less force needed to turn handle on Dynamo after it is disconnected?
- There is no induced current
- So no magnetic field around the wire
- To oppose the movement of the coil
