Hello everyone, it's been a long time...
I've never really been that good at all in physics, but I've compiled a few notes and formulas for the theory questions, just in case someone needs a list of formulas....
It's not much, but hopefully other users will help me add more and correct me if I'm wrong (which may most certainly be so)...
1) Uncertainty:
If you get 2 or more measurements that have an uncertainty of x ± y, for example (R = V / I and the measured value of V is 5 ± 0.01 V and I is 1 ± 0.01) then you use this:
( ( dX / x ) ± ( dY / y ) ) * 100% (where dY is the uncertainty of Y (i.e 0.01 in this case) and Y is the measured value (i.e 1 in this case) )
2) Precision vs Accuracy:
Precision is consistency, but accuracy is how close something comes to the original value, for example if I am measuring the values of g and I get {9.81, 9.79, 9.80, 9.89} then it's both precise and accurate; if I get {8.25, 7.2, 1.5, 12.77} then it's neither precise nor accurate; if I get {8.24, 8.3, 8.4, 8.25} then it's precise but not accurate
3) Plastic and elastic deformation:
I've never really understood plastic and elastic deformation but now I do so it turns out it's easy-ish...plastic deformation is when a material undergoes deformation beyond its elastic limit and elastic deformation is deformation of a material within its elastic limit.
4) Limit of proportionality and elastic limit are not the same. A material may deform proportionally up to a point, but it may return back to its original position even after crossing the limit of proportionality (straight line)
5) For double slit, use ax/D where D is the distance in metres from the slit and the wall (can someone help me on a and x, I get confused easily)
6) Electricity:
Voltage is the same in a parallel circuit, but not current; current is the same in a series circuit but not voltage. Power = voltage * current (P = VI); Power = charge * voltage (W = VQ); Energy (J) = current * time * voltage (E = ItV); Resistance = voltage / current (R = V/I); Resistance = Resistivity * (Length / cross-sectional area) (R = p(L/A)).
7) Equations of motion:
Only apply to objects with constant speed / acceleration (I might be wrong though); they are:
v = u + at; s = ut + 0.5(a * t squared); v squared = u squared * 2 * a * s; a = (v - u) / t; s = 0.5(u + v) * t
Formulae:
P = VI; W = VQ; E = ItV; R = V/I; dsinX = nL; R = pL/A; E = ItV; F=kx; E = 0.5(Fx) or E (joules) = 0.5(k * x squared);
I'm tired, I'll update this post (if I can) later tomorrow, possibly after my exam. Sorry if it's poorly formatted and hurts your eyes
I've never really been that good at all in physics, but I've compiled a few notes and formulas for the theory questions, just in case someone needs a list of formulas....
It's not much, but hopefully other users will help me add more and correct me if I'm wrong (which may most certainly be so)...
1) Uncertainty:
If you get 2 or more measurements that have an uncertainty of x ± y, for example (R = V / I and the measured value of V is 5 ± 0.01 V and I is 1 ± 0.01) then you use this:
( ( dX / x ) ± ( dY / y ) ) * 100% (where dY is the uncertainty of Y (i.e 0.01 in this case) and Y is the measured value (i.e 1 in this case) )
2) Precision vs Accuracy:
Precision is consistency, but accuracy is how close something comes to the original value, for example if I am measuring the values of g and I get {9.81, 9.79, 9.80, 9.89} then it's both precise and accurate; if I get {8.25, 7.2, 1.5, 12.77} then it's neither precise nor accurate; if I get {8.24, 8.3, 8.4, 8.25} then it's precise but not accurate
3) Plastic and elastic deformation:
I've never really understood plastic and elastic deformation but now I do
so it turns out it's easy-ish...plastic deformation is when a material undergoes deformation beyond its elastic limit and elastic deformation is deformation of a material within its elastic limit.4) Limit of proportionality and elastic limit are not the same. A material may deform proportionally up to a point, but it may return back to its original position even after crossing the limit of proportionality (straight line)
5) For double slit, use ax/D where D is the distance in metres from the slit and the wall (can someone help me on a and x, I get confused easily
)6) Electricity:
Voltage is the same in a parallel circuit, but not current; current is the same in a series circuit but not voltage. Power = voltage * current (P = VI); Power = charge * voltage (W = VQ); Energy (J) = current * time * voltage (E = ItV); Resistance = voltage / current (R = V/I); Resistance = Resistivity * (Length / cross-sectional area) (R = p(L/A)).
7) Equations of motion:
Only apply to objects with constant speed / acceleration (I might be wrong though); they are:
v = u + at; s = ut + 0.5(a * t squared); v squared = u squared * 2 * a * s; a = (v - u) / t; s = 0.5(u + v) * t
Formulae:
P = VI; W = VQ; E = ItV; R = V/I; dsinX = nL; R = pL/A; E = ItV; F=kx; E = 0.5(Fx) or E (joules) = 0.5(k * x squared);
I'm tired, I'll update this post (if I can) later tomorrow, possibly after my exam. Sorry if it's poorly formatted and hurts your eyes
