In the equation Q = m x (T2 - T1) x C, what does Q represent?

• A. Heat
• B. Change in thermal energy
• C. Energy
• D. Mass

Answer: (B)

The key idea is that Q represents the amount of energy transferred as heat. In the equation, m is the mass, c is the specific heat capacity, and ΔT is the change in temperature (T2 − T1). Multiplying these tells you how much heat energy is added to or removed from the object to produce that temperature change. That heat transfer changes the object's thermal (internal) energy in a simple scenario, so describing Q as a change in thermal energy is the most accurate way to capture what the equation is measuring. The other options don’t fit because Q is not just general energy, not simply the mass, and while heat is the transfer of energy, the standard way to express what the equation computes is the amount of heat transferred that causes the temperature change.