OCR Physics A G484 - The Newtonian World - 11th June 2015

Can someone explain specific heat capacity please?
If there's a lower specific heat capacity, why does temperature of the object fall more quickly?

Can someone explain specific heat capacity please?
If there's a lower specific heat capacity, why does temperature of the object fall more quickly?

Specific heat capacity is the energy required to raise the temperature of a unit mass of a substance by a unit temperature rise.

So a substance with a higher c value requires more energy to raise its temperature by value x.
A substance with a lower c value requires less energy to raise its temperature by value x.

Hence substance c will cool quicker because as energy is lost, there is a greater temperature decrease per unit time.


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Specific heat capacity is the energy required to raise the temperature of a unit mass of a substance by a unit temperature rise.

So a substance with a higher c value requires more energy to raise its temperature by value x.
A substance with a lower c value requires less energy to raise its temperature by value x.

Hence substance c will cool quicker because as energy is lost, there is a greater temperature decrease per unit time.


Posted from TSR Mobile

Imagine SHC as the ability for an object to retain heat

Hey guys, whats your definition for centripetal force...I dont remember seeing it asked in the exam so it wasnt on the MS? Hmmm mines sounds very plain and probably wont gain any marks?

The resultant force towards the centre of the circular motion at 90 degree to the velocity...

When a resultant force is perpendicular to an object's velocity it will make the object describe a circular path.

I would say when it always acts perpendicular.

Quesiton 3c on Jan 2011 paper, I don't understand why the line going from 0C to -18C is suppose to be steeper than the line going from 18C to 0C. I thought If the specific heat capacity is lower then the substance will cool down slower resulting in a more shallow gradient but apparently that's incorrect

Q4biii Jan 2011 how we know is we should use x=Asin(2pieft) or x=Acos(2pieft), it doesn't tell us if time was started at a high/low tide or the midpoint of the tide, although in the mark scheme it does say accept sin or cos but wouldn't that make a big difference

Its fine, you can use either sin or cos. They allow this because you're not doing any calculating with it, they just wanted an expression.

But in a SHM question if the pendulum or spring-mass is released from max amplitude then use cos, if it is released from equilibrium position then use sin.

Assuming they lose it at the same rate?

So does the gravitational field strength always equal the acceleration of an object due to the gravitational field at all distances?

Yeah as long as there are no other forces.