Physics: Post your doubts here!

[Kanekii]

D right?

 

[A*****]

D right? View attachment 64145

Yes

 

[Kanekii]

View attachment 64144 i am confused with both questions ugh

Q15 C

 

[Mush999]

View attachment 64144 i am confused with both questions ugh

PE= KE + PE

it has gained a height and also moving after it slides down!

PE = KE + PE

mgh = 0.5mv^2 + mgh
(m is a constant so cancel it out!)

gh = 0.5v^2 + gh

9.81*h = 0.5*1.4^2 + 9.81*40*10^-2

h= 0.50//

 

[potatocorn12]

PE= KE + PE

it has gained a height and also moving after it slides down!

PE = KE + PE

mgh = 0.5mv^2 + mgh
(m is a constant so cancel it out!)

gh = 0.5v^2 + gh

9.81*h = 0.5*1.4^2 + 9.81*40*10^-2

h= 0.50//

Q15View attachment 64146 C

Thank youuu,i suck at physics lol

what about 17 tho

 

[mariam001]

for the feb march paper what is the explanation for question 14 ?

 

[Kanekii]

Is the answer B?

 

[A*****]

Thank youuu,i suck at physics lol

what about 17 tho

 

[A*****]

Is the answer B? View attachment 64147

Yeah!

 

[Mush999]

Thank youuu,i suck at physics lol

what about 17 tho

No problem!
Q17.

Total energy in the fuel
34 × 1.5 × 10^4 = 5.1×10^5kj

And it states that 1.5 × 10^4 is vol used per hour

So per second second 5.1×10^5/60×60 = 141.67kw

So wasted power is 141.67-40= 101.67≈ 102kw

 

[Tom Sewage]

need help, how to solve this question

 

[A*****]

View attachment 64149

need help, how to solve this question

At highest point, vertical comp of velocity is zero and horizontal comp is v cos45= 0.707v
New kinetic energy= 0.707²= 0.50E

 

[Tom Sewage]

View attachment 64144 i am confused with both questions ugh

 

[Ayesha_m01]

ANS is C..?

 

[Tom Sewage]

Is the answer B? View attachment 64147

Hi can u explain me how u got the answer as B

 

[Tom Sewage]

At highest point, vertical comp of velocity is zero and horizontal comp is v cos45= 0.707v
New kinetic energy= 0.707²= 0.50E

thanks

 

[A*****]

Hi can u explain me how u got the answer as B

 

[potatocorn12]

If anyone can post the paper 22 or give me all the questions from it, I can give solid predictions on what would come up as the topics from which questions are chosen are often interlinked for paper 1, 2 and 5.

well we had base units question then a momentum question where we were to find theta and i guess kinetic energy and then we had kinematics question..about finding velocity displacement and stuff based on graph given with a diagram of a boy on sledge and there were components of weight...involved.Then for electricity,they asked kirchoffs second law, then there wass a diagram of circuit whicih i guess was something like a potentiometer question because we had to find resistance and current and write down relation between two wires and like how to increase the resisitivity or like ratio between length or smth.Then we had an upthrust,weights question where a cylinder was under water and held by a wire,we had to find its weight i guess and we were given the density and fluid it was in,plus we also had to find tension in the wire that was holding it . for waves it was stationary waves,simple question on finding wavelength(a tube was drawn i guess with )..Last question was simple,it was a a B- decay and a quark composition and they asked if nucleas formed after b- decay would be an isotope of the nucleas atfirst or not...Thats all what i rememeber,so can you predict anything?

 

[Krypton36]

View attachment 64151
ANS is C..?

MV1 - 2MV2 = 0
V1 = 2V2...... ( i)

Now! ( 1/2 mV1^2) / (1/2 (2m)V2^2)
You replace i.
Then get 2/1

 

[Hisham Khan]

Pls help me withthis