Physics: Post your doubts here!

[Thought blocker]

Q13 ?

 

[Hadi Murtaza]

Q8,9,13,18,26 Please help me[/quote]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w09_qp_12.pdf

Q8,9,13,18,26 Please help me

Q.26
When charge Q is at position of q. It exerts a force of da electric field strength on da charge n its magnitude depends upon da strength of da electric field n da amount of charge on Q.
F = Eq
E = F/q

 

[Thought blocker]

Q8,9,13,18,26 Please help me

Q.26
When charge Q is at position of q. It exerts a force of da electric field strength on da charge n its magnitute depends upon da strength of da electric field n da amount of charge on Q.
F = Eq
E = F/q[/quote]
I thought it was answered by Zep.. something Copycat

 

[Hadi Murtaza]

Q13 ?

Im kindof lousy at explaining dis 1

Initial E = E[x] + E[y]
Final E = E[x] only
So Final E = (1/2) Initial E

 

[Thought blocker]

Im kindof lousy at explaining dis 1

Initial E = E(x) + E
Final E = E(x) only
So Final E = (1/2) Initial E

Projectile me aisa sab ata hain ?

 

[Hadi Murtaza]

Q.26
When charge Q is at position of q. It exerts a force of da electric field strength on da charge n its magnitute depends upon da strength of da electric field n da amount of charge on Q.
F = Eq
E = F/q

I thought it was answered by Zep.. something Copycat [/quote]
Wat

 

[Hadi Murtaza]

Projectile me aisa sab ata hain ?

lol i wanted 2 write ( y ) instead of

 

[Thought blocker]

I thought it was answered by Zep.. something Copycat

Wat [/quote]
Zepudee ne wo answer diya thana ?
I saw ur previous deleted post

 

[Hadi Murtaza]

Wat

Zepudee ne wo answer diya thana ?
I saw ur previous deleted post [/quote]
dude Zepudee is da 1 whos asking da questions -_-

 

[Thought blocker]

Zepudee ne wo answer diya thana ?
I saw ur previous deleted post

dude Zepudee is da 1 whos asking da questions -_-[/quote]
Acha... sorry

 

[Hadi Murtaza]

dude Zepudee is da 1 whos asking da questions -_-

Acha... sorry [/quote]
I deleted da old post cuz i qouted my own post by mistake

 

[Thought blocker]

Acha... sorry

I deleted da old post cuz i qouted my own post by mistake[/quote]

 

[Snowysangel]

Which formula could be correct for the speed v of the ocean waves in terms of the density p of sea water, the acceleration of free fall g, the depth of the ocean h and the wavelength, lambda?

 

[Zepudee]

Q.9
Impulse (or change in momentum) = Force * time
Impulse = 60 * 0.5 = 30 Ns

Initial momentum of trolley = 30 kg * 3 m/s= 90 Ns
Impule (or change in mometum) = 30 Ns
So final momentum = 90 - 30 = 60 Ns
Final speed = final momentum/mass

Aww thanks. totally forgot to find the speed!! Thank you so so much!!

 

[Hadi Murtaza]

ur most welkum. btw i did find da speed, check out my post

 

[Zepudee]

Im kindof lousy at explaining dis 1

Initial E = E[x] + E[y]
Final E = E[x] only
So Final E = (1/2) Initial E

Sorry Hadi, but can you please explain a bit more about this?

 

[Zepudee]

ur most welkum. btw i did find da speed, check out my post

Ohhh yeah, haha i mean me

 

[Zepudee]

Q.18
Pressure = F/A = W/A = mg/A = g * m/A
m/A = Pressure/g

Density = m/V = m/A * 1/h
Density * h = m/A
Denisty * h = Pressure/g
Denisty = (Pressure/g) /h
Density = Pressure/(g * h)
Density = 15 200/(10 * .8)
Density = 15 200/8
Density = 1900 kg/m³
Answer: B

Hadi Murtaza Oh ya, why Density=m/A*1/h? Heh heh

 

[Hadi Murtaza]

Sorry Hadi, but can you please explain a bit more about this?

yes ofcourse. dat wuz a crappy explanation anyway.

Vx = V*cos(45) = V * (1/√2) = V/√2
Vy = V*sin(45) = V * (1/√2) = V/√2

E = (1/2) * m * (v)²
E = Ex + Ey

Ex = (1/2) * m * (V/√2)²
Ex = m/2 * V²/2
Ex = mV²/4

Ey = (1/2) * m * (V/√2)²
Ey = m/2 * V²/2
Ey = mV²/4

Initial E = Ex + Ey = (mV²/4) + (mV²/4)
Initial E = mV²/2

^^This is da moment when da object is launched in da air.

At maximum height, vertical velocity becomes 0 which means Vy = 0 , so Ey also becomes 0
Hence
Final E = Ex only
Final E = mV²/4

Now compare Final E wid Initial E.
Final E is 1/2 of Initial E
So answer is 0.5E

 

[Hadi Murtaza]

Hadi Murtaza Oh ya, why Density=m/A*1/h? Heh heh

Volume = length * width * height
length * width = Area = A
So Volume = A * height or A * h