Physics End Of Year Mistakes Flashcards
Electricity
If you want to get firm point x to y what to do
Find all routes to get there
Make a new ciruit
Now do question
Electric yt
IF TWO CELLS REVERSED WHAT TO DO TO FIND OUT
These are LIKE VECTORS
If one cell reversed, doesn’t means - one v
You have TO CANCEL EACH OTHER OUT
Draw arrows and cancel out now the q
Electricity
If you lose 1% power
You lost what too?
1% volts
Current is the Same however because ratios is same
Momentum , what is actually conserved in collision
What about the total force after collisions
Momentum of each trolley is not conserved but momentum of whole system
As force = change in momentum over time, as final momentum= initial momentum, there is no change and so there is never any force
What about kinetic energy is this conserved?
No unless it is elastic which needs same mass too
ACTUAL COHERENT def
CONSTANT PHASE DIFFERENCE (not the same)
And same frequency which causes this
What does impulse give you?
What misconception you have about impulse and change of momentum in one object
Change if Monstrum momentum of the object force being applied to
Basically Montur conserved calm but for all objects, for one object it’s not , there is a change of momentum
So if you know inits momentum you can work out a value if initial was 0!
Uncertainty addition ?
You don’t, only when multiply or divide
How is a massive object dropping momentum conserved
The EARTH IS PART OF SYSTEM (hinted by massive)
- so momentum before is 0
So as ball moves down and gains momentum, thr earth needs to move towards it and gain speed opposite direction so Monteur cinserved !
Momentum new equation too in velocity
Mass x change of velocity = mass x change in velocity as they cinstsnt
Why does train going up less distance
This is because component of WEIGHT acts against the motion
As a result resultant force is greater for same average force breaking, so deceleration is greater so distance is less
Bruv in upthrust don’t just assume what straight away
Thst the upthrust = the weight of the thing , it might not it might be higher aswell if completely dubmerged
Why do heaters not obey oh,s law
Becsuse ohm law states that voltage is proportional to current ad tempertaure is constant
Here temp is not constant oh,s law will not apply
ACTUAL DEFINITION OF PHASE DIFFERENCE
The difference in degrees , radians or angles between pointd on same wave or similar pointd between two waves
IF SOMETHING FALLING DOWN RAMP HOW TO FIND FINAL VELOCITY !
This is Average velocity
USE SUBAT S = 1/2. U +V x t
