OCR A 2021 Paper 2 - A-level Physics Past Paper

[@henryrussell3388]

what's with the random Irish accent at 6:20 😂

[@Vlad-rk5go]

At this point I just want to join the army.

[@lilboom7565]

yea paper 1 got me questioning if this is all worth it lmao

[@HTT-zu4iz]

​@@lilboom7565 have u done the pure math, dude im fuked.... totally fuked up :-/

[@zolvyy]

@@lilboom7565 💀fax

[@Anyting9OnTopGrrr]

What did u man ending up getting for physics

[@Vlad-rk5go]

@@Anyting9OnTopGrrr B. By the way, it turns out that Sunak heard me, just a bit late.

[@jameelruhomaun6307]

for question 6, why does the value get reduced by 10 percent each time?

[@terra3665]

Really appreciate the video!
One question, how come you subtract the e.m.f in question 18?

[@theobird1918]

its because the currents are flowing in opposite directions so the one with more emf will overcome the other

[@atrs]

For question 12 since it’s asking for flux linkage would you not also have to divide 1.04x10^-3 by the number of turns (200) to leave with just phi so the answer should be B if I’m not mistaken

[@sofiaalonss]

hi will you do the 2022 and 2023 papers?

[@zxin2308]

7:42 , why not 100hz?

[@tebluspy]

Because the time period of the wave is 5ms, f=1/T means the frequency is 200Hz

[@Sam-dv8mt]

wait what's the logic behind 3:00 is it taking the most direct path or something

[@angejo5591]

Current can only flow one way through LED. Shown by the bar on top of the triangle. If “only two are lit” which is stated, in order for P or R to be lit. Q Also has to be lit. That’s not 2 LEDs thas 3. Also pretty sure current takes most direct path.

[@Sam-dv8mt]

@@angejo5591 oh that makes sense ty

[@danielbaker583]

@@angejo5591 why cant it go through R?

[@angejo5591]

@danielbaker583because think of current as “wanting to get back to the negative terminal”. It won’t go through R because that is not the path of least resistance. Each LED will have some internal resistance

[@ollie6809]

I don’t understand why you don’t convert to metres on question 21 for the 0.85 and 2.1, as converting to metres gives a different answer to leaving it.

[@s0ph_r0se1]

It doesn't actually give a different answer, its 0.85 per cm so 0.85 x 10(2) and 2.1 cm is 2.1 x 10(-2)

[@magicharp5295]

i made same mistake, the constant was in per cm already

[@ollie6809]

@@s0ph_r0se1 thanks so much

[@romaisaaftab5692]

for question 19 part b , didnt they ask for absolute uncertainty? How do we give the uncertainty as absolute uncertainty?

[@kujojotaro3035]

(percentage uncertainty)/100 and then multiply that to your value for B

[@yamatosennin9249]

Why, when finding the ultrasound intensity, was the impedance z1 1?

[@yamatosennin9249]

Just realised tissue F was a thing

[@BurhanSiddiqui-si4mk]

@@yamatosennin9249 Same here lol.
I thought it was a ratio, didn't think they were giving us the actual values of the density and and speed of ultrasound

[@aryanvirdi458]

6:56, 3 x 60 gives us 60?!????

[@ScienceShorts]

Nah, I messed up by writing 3x again

[@teacupcakes2739]

happy days

[@vi4482]

thank you!

[@vinethkawmududesilva3662]

thanks for uploading