Physics: Post your doubts here!

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Sorry, I think my explanations were vague. Okay let me describe the thing again:

The upthrust is the weight of water displaced. The amount of water displaced has nothing to do with the density. The aomunt of water displaced depends on the volume of the cuboid. Volume is same for all the cuboids, so they will displace equal amounts of water. So they will have the same upthrust. :p Clear now?
YEAH THANKS REALLY.
 
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Can someone do part c please. Need it urgent.
Using the formula you proved above, you can find E, the Kinetic Energy required to statisfy their condition.
Next, using the relation E = VQ, you can find V. This is because the kinetic energy is being provided by the electric potential energy. You already know the charge and mass of an electron from the data provided at the beginning of paper.
 
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Paper 4 (A Level Structured Questions): The assessment of core and applications topics will be integrated. There will no longer be a section A and a section B.

What do they mean by the first statement ?
 
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Paper 4 (A Level Structured Questions): The assessment of core and applications topics will be integrated. There will no longer be a section A and a section B.

What do they mean by the first statement ?
The applications will be merged with the questions. There will not be a separate section B for applications.
 
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someone help!!!!........
9702/s14/qp13/question 32

Thanks in advance.....
The electric field strength, E, is given by this formula:

E = F/Q (where F is force, Q is charge and E is electric field strength)

We know F = ma, so E becomes:
E = ma/q ----(i)

You're given that, K.E = k. Use the equation of K.E (1/2mv^2) to find the value of m and substitute this value of 'm' into (i)
m = 2K/v^2 ---- substituting in (i)

(i) will become:
E = ( (2K/v^2) * (a) )/ q ------(ii)

Now use the equation of motion: v^2 = u^2 + 2as
The charge starts moving from rest, so initial speed (u) is zero. And it covers a distance of 'd' for reaching plate Y, so s=d. So,
v^2 = 2ad ---- put this one into (ii)

E = ( (2K/2ad) * (a) )/ q

Simplify it, you'll get :

E = K/qd

So the answer is C.
 
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Using the formula you proved above, you can find E, the Kinetic Energy required to statisfy their condition.
Next, using the relation E = VQ, you can find V. This is because the kinetic energy is being provided by the electric potential energy. You already know the charge and mass of an electron from the data provided at the beginning of paper.
Thanks legend
 
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The electric field strength, E, is given by this formula:

E = F/Q (where F is force, Q is charge and E is electric field strength)

We know F = ma, so E becomes:
E = ma/q ----(i)

You're given that, K.E = k. Use the equation of K.E (1/2mv^2) to find the value of m and substitute this value of 'm' into (i)
m = 2K/v^2 ---- substituting in (i)

(i) will become:
E = ( (2K/v^2) * (a) )/ q ------(ii)

Now use the equation of motion: v^2 = u^2 + 2as
The charge starts moving from rest, so initial speed (u) is zero. And it covers a distance of 'd' for reaching plate Y, so s=d. So,
v^2 = 2ad ---- put this one into (ii)

E = ( (2K/2ad) * (a) )/ q

Simplify it, you'll get :

E = K/qd

So the answer is C.
thanks alot!
 
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This question is from a mock exam and I do not know its answer. I coudn't find the paper. And answer with the explanation would be appreciated.
View attachment 60005
View attachment 60006
I think it's C. Because in a stationary wave, the points in adjacent loops are out phase with each other. So if the displacement of a point in one loop is S then in the adjacent loop, it should be -S.
 
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