Physics: Post your doubts here!

[amal sharkawi]

CAN ANYONE ANSWER PLZZZZZZ

 

[Mathemagical]

View attachment 54382

CAN ANYONE ANSWER PLZZZZZZ

 

[Mathemagical]

View attachment 54366
How D?

When the temperature is reduced, the resistance of the thermistor increases. Therefore, a larger proportion of the emf will flow across the thermistor and the voltmeter reading will increase.

 

[Ahmed Aqdam]

How to do this? ans is C

When finding between Y and Z, the other two would be in series and in parallel with the 5 Ω one.
1/2R+1/5=1/2.5.
R=2.5 Ω
Now 5 Ω and of the 2.5 Ω resistors will be in series and these will be in parallel to the other 2.5 Ω resistor when calculating between X and Y. Calculate to get 1.9 Ω.

 

[Ahmed Aqdam]

View attachment 54364
How C?
E = FL/Ax
E = 2L/(A/4)
E = 8x more ??

Same steel means same Young Modulus. The difference will be in extension.

View attachment 54367
How B?

Momentum before collision: 8+4=12
Velocity after collision: 12/6=2 ms^-1
KE= 0.5*6*2^2=12 J

View attachment 54368
I know the answer is C but which states do A B and D represent?

None. They are just a mixture of properties of solids, liquids and gases.

 

[Maayee]

can anyone help me with question no. 6. the answer is D
http://onlineexamhelp.com/wp-content/uploads/2014/02/9702_w13_qp_13.pdf

 

[Ahmed Aqdam]

can anyone help me with question no. 6. the answer is D
http://onlineexamhelp.com/wp-content/uploads/2014/02/9702_w13_qp_13.pdf

Find the percentage uncertainty in diameter and multiply it by 3 as radius is cubed in the formula of volume. Add the percentage uncertainty in mass.

 

[Mathemagical]

can anyone help me with question no. 6. the answer is D
http://onlineexamhelp.com/wp-content/uploads/2014/02/9702_w13_qp_13.pdf

Density = Mass/Volume

Volume of sphere = 4/3*pi*r3

Percentage uncertainty of diameter = 0.02/2.20*100 = 0.909%
Percentage uncertainty of mass = 0.005/0.506*100 = 0.988%

Since the diameter has to be halved to find the radius and then cubed, we multiply the uncertainty by 3.

Therefore, 3(0.909) + 0.988 = 3.7%

 

[Maayee]

Find the percentage uncertainty in diameter and multiply it by 3 as radius is cubed in the formula of volume. Add the percentage uncertainty in mass.

Thank u sooo much, you are such a big help

 

[Maayee]

Density = Mass/Volume

Volume of sphere = 4/3*pi*r3

Percentage uncertainty of diameter = 0.02/2.20*100 = 0.909%
Percentage uncertainty of mass = 0.005/0.506*100 = 0.988%

Since the diameter has to be halved to find the radius and then cubed, we multiply the uncertainty by 3.

Therefore, 3(0.909) + 0.988 = 3.7%

Thank you

 

[princess Anu]

No, it has nothing to do with that. The element with the greatest mass to charge ratio has the lowest speed.

Could you please explain why?

 

[Mathemagical]

Could you please explain why?

It's simple common sense. Imagine a particle with a large mass but a small charge. It has a bigger inertia, so it would have a lower speed.

 

[princess Anu]

what is the resistance between P& Q?

ans is o.5ohms

 

[Ahmed Aqdam]

Could you please explain why?

It's simple common sense. Imagine a particle with a large mass but a small charge. It has a bigger inertia, so it would have a lower speed.

There's a formula for it too.
F=qE
ma=qE
a=qE/m
P.d. is same so E will be constant too.
Hence less q/m ratio means less acceleration.

 

[The Chill Master]

can anyone draw the graph

 

[Autumn98]

help me with this question pls.

 

[Autumn98]

I need help with this too, I got D but the right answer is A....

 

[Autumn98]

Help again...please

 

[Autumn98]

Help!!!!!!

Both questions......

 

[nehaoscar]

Thanks! But even if Q is moving fastest, it's at equilibrium position, so why won't its displacement be zero?