# Need help with physics symbols in question

1. Aug 26, 2008

### Tweek

1. The problem statement, all variables and given/known data

I'm taking an online physics course and I do not understand what the symbols mean in the question.

The question is: Which of the following is a shorthand way of stating that "the temperature change of a substance is directly propertional to the quantity of heat added"?

A. Q ¡Ø m
B. m ¡Ø Tf - Ti
C. Q ¡Ø T
D. Q = Tf - Ti

I know that Q means heat. I'm guessing that Tf is final temp and Ti is initial temp. I also know that m is for mass. However I have no idea what ¡Ø means.

2. Relevant equations

My text book does not use this ¡Ø symbol and I have searched online but I can't figure out what it is. Can anyone tell me what ¡Ø means?

3. The attempt at a solution

I think the answer is C and if I can't get any help here I'm going to choose that answer.

2. Aug 26, 2008

### CompuChip

Do you mean: $\propto$ ?
That symbol means: proportional to.

For example, instead of writing: "The formula for y is $y = k x^2$ with k some constant" physicists tend to say "y is proportional to the square of x", or "$y \propto x^2$". They just do it to indicate the shape of the function, without going into details about precise (often numerical) prefactors and shifts.

For example, $3 (x - a)^2 + 16 \pi$ is also proportional to $x^2$.

3. Aug 26, 2008

### Tweek

Yeah I am familiar with the proportional to symbol but on the work sheet it gives this ¡Ø
It might be an error. In this case I think c makes the most sense. I think answer c means temp change is directly proportional to the quantity of heat added.

4. Aug 26, 2008

### CompuChip

If it really says that, it must be an error. Probably it was copy/pasted from another document and the proportionality symbol wasn't copied correctly.

Anyway, why did you discard B?

5. Aug 26, 2008

### Tweek

The reason why I discarded B is because it has mass in the formula and it doesn't have the Q for heat.

BTW I really appreciate your help. Thanks :-)

Last edited: Aug 26, 2008
6. Aug 26, 2008

### CompuChip

Ah, :rofl: I missed that. I just thought the Tf - Ti looked very tempting. But of course, proportionality to T also means proportionality to (T - T0)

You are most welcome.