Mistakes Flashcards
When using ideal voltmeter and trying to find out etc what should you do
Find out currents first, don’t fall into trap that ideal so takes all voltage, what you should do is think ideal so no current, so it’s possible to find current, now find out voltages of others etc, need to use this approach
Ideas about gpe and ke and resistive forces
Remember ideally ALL THE ENERGY will be constant in a system, so total GPE AND KE at the top should equal total GPE AND KE at the end, but in reality loses by resistance, this what need to remember
This way can find how much lost if done total
Gravitational potential energy , where do you use height m frim?
FROM THE CENTRE OF MASS, ofc, as all mass concentrated there!
Sugar equations, the time when something thrown returns to this height can be found by
1) either finding quadratic for t
2) or easier is assuming the velocity is - when it was going upwards, due to conservation of energy
- can make a much easier us at equation
Graph transformations
Just make sure you use the minimum point to locate the graph in completed square form, then use coefficients to give positive or negative x graph
Remember that gradient of the v t graph is?
How to do that question Bakst analysing graph?
Graph proportional where grad is 5
So find equations for all see if promotional then see if gradient = 5!
How much distance does a particle on a wave actually travel?
It don’t travel anywhere, only up or down, so in one wave, 4 x A
Find out how many waves have happened, multiplied by 4a
On a pulley what are forces acting on it?
The force holding it up
And two tension forces going down in Esther side!! Thus the force holding up is two times the tension ti stop it from accelerating downwards!
This is the force in the coupking
FORMULA FOR EXTERNAL ANGLE!
Is 360/n not internal!
Remember newton third law key part (ending)
That the forces are OF EQUAL TYPE! So to check make sure they are
For finding distinct trots to some long equation what to do?
Remember root just solutions, so if equal to something it’s just solutions to that, no need to rearrange for 0 etc
Just say if y= k wheee will I get 4 intersections , between these two points, find them and go on.
What is definition of increasing function?
When derivative is GREATER THAN KR EQUAL TO 0!
Remember if graph not straight for v t for throwing up what does this show
That there is air resistance, thus energies are lost!
BIG MISTAKE
How to compare surfs?
Make sure to convert to surf form first, then you can easily compare them!
Remember log rules
If you add you multiply add if you subtract you divide etc
