I with this MCQ question pleae

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The discussion centers around a multiple-choice question related to heat transfer and specific heat capacity. The poster initially struggles with understanding why the answer is D and is prompted to show their work. Key points include the clarification that identical heaters provide the same power, but heat absorbed varies based on the properties of the objects. The poster realizes a misunderstanding regarding energy provided and seeks to calculate specific heat capacity using mass ratios. Ultimately, the conversation emphasizes the importance of using the power ratio rather than assuming mass values for accurate calculations.
Shiv Narayanan
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< Mentor Note -- Poster has been warned to show their work in future schoolwork threads >[/color]

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Hello! I need help with this question. The answer is D but I don't understand why :/ Thanks!
 
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Please post your attempt .

Hint : What is formula for ΔQ ? What is power provided ?
 
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Hello, Thanks for replying!
 

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Why is Q1 = Q2 ?

Heaters are identical , and so power provided by them will be the same . The heat absorbed by the objects in some time ' t ' will depend on their own properties . It will not necessarily be the same for both .
Try again .

Hope this helps .
 
Oh Yes.. I read the question wrongly. I thought amount of energy provided is the same.

So, if I am not wrong, the gradient of the graph is the specific heat capacity and since mass of N is 2 times the mass of M, in this case, I can just take the mass of N to be 2kg while the mass of M to be 1kg right? (For me to be able to calculate)

I find the gradient of N and divide it by 2 as heat capacity is per kg.Then I have to compare with the gradient of M and derive the ratio.. Am I right?
 
ΔQ = m*c*ΔT ,
∴ P = ΔQ / ΔT = ?

Shiv Narayanan said:
So, if I am not wrong, the gradient of the graph is the specific heat capacity and since mass of N is 2 times the mass of M, in this case, I can just take the mass of N to be 2kg while the mass of M to be 1kg right? (For me to be able to calculate)
No , I think it looks more like ( ΔT / Δt ) .
And no , you can't assume the masses as so . Use P1 / P2 ratio .
 
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