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Physics: Post your doubts here!

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For the first part, the circuit is:
the upper two resistors are in series
The lower two resistors are in series
And the the one in the middle is well.. alone xD
And all the above are in parallel to each other
I made that diagram just for the second part, it is not applicable to part i

Thankyou.....
 
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Is the answer C?
Note: I am not complete sure about this question
extension = F * l/A*young modulus

Now in the model, all the linear dimensions are one tenth.

Now, the length, width and height of the load are 10 times the one in the model. Thus 10*10*10 = 1000 times the volume of the load in the figure. As volume and mass are directly proportional, the mass should also increase 1000 times, and so should the weight.

Now, the radius of the wire in the model is times the one in the model (linear dimensions) Thus the area should be 100 times more than the one in the model due to the square in the area of a wire

The length of the wire would just be more by a factor of 10.

The young modulus should not change, as it is the same for a material

(1000 * 10/100)/1 = 100

Kindly confirm about this one.



Can u solve this question as well?
 

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I have one more question.... If someone could answer it... I would be really thankful.... :)
 

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Can u solve this question as well?
Wall area = A m²
Volume of air colliding with wall per sec .. V/s(m³/s) = u(m/s) x A(m²) = uA
Mass colliding per sec .. m/t (kg/s) = V/s(m³/s) x D(kg/m³) = uA D

Force = rate of change of momentum ..
F = (mv - mu) / t = m/t (v-u) .. .. assuming the air comes to rest, then v = 0 and ..
F = -(m/t)u .. .. (against the motion)

F = (uAD)u .. .. u²AD .. .. ►F = 33² x A x 1.20 .. (N)
 
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Wall area = A m²
Volume of air colliding with wall per sec .. V/s(m³/s) = u(m/s) x A(m²) = uA
Mass colliding per sec .. m/t (kg/s) = V/s(m³/s) x D(kg/m³) = uA D

Force = rate of change of momentum ..
F = (mv - mu) / t = m/t (v-u) .. .. assuming the air comes to rest, then v = 0 and ..
F = -(m/t)u .. .. (against the motion)

F = (uAD)u .. .. u²AD .. .. ►F = 33² x A x 1.20 .. (N)

Thankyou
 
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Wall area = A m²
Volume of air colliding with wall per sec .. V/s(m³/s) = u(m/s) x A(m²) = uA
Mass colliding per sec .. m/t (kg/s) = V/s(m³/s) x D(kg/m³) = uA D

Force = rate of change of momentum ..
F = (mv - mu) / t = m/t (v-u) .. .. assuming the air comes to rest, then v = 0 and ..
F = -(m/t)u .. .. (against the motion)

F = (uAD)u .. .. u²AD .. .. ►F = 33² x A x 1.20 .. (N)

Can u solve this question as well
 

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http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w04_qp_2.pdf
"Q6(a)(i)", I didn't get the marking scheme on this one but is the answer something like this that resistance decreases with increasing p.d. since its an increasing curve (current is increasing)

It can be seen from the upward bending curve that the current does not increase proportionally to the voltage. It increases more than the voltage, which hints that with increasing voltage, the resistnace of C decreases.
 
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Can u solve this question as well
Not sure about this one. Here's what the examiner report says:
The answer to this question cannot reliably be obtained by guesswork. Eliminating the pressure at P gives
(h1–h2)ρg = 8000 Pa, so (h1–h2) = 0.060 m. D is the only answer that fits.
 
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