Question

Which one of the following equations specifies an isobaric process? \([Q = \text{heat supplied}, \Delta P, \Delta V \text{ and } \Delta T \text{ are change in pressure, volume and temperature respectively}]\)

• A. \( Q = 0 \)
• B. \( \Delta T = 0 \)
• C. \( \Delta V = 0 \)
• D. \( \Delta P = 0 \)

Hint:

Prefixes: “iso” means same. “baric” refers to pressure (bar). So isobaric = same pressure.

Answer 1

The Correct Option is D

Step 1: Read what the question wants.
We have to pick the condition that describes an isobaric process. The word may look heavy, but it just hides a simple idea.

Step 2: Break the word into pieces.
The prefix 'iso' means 'same' and 'baric' comes from pressure. So 'isobaric' simply means the pressure stays the same all through the change.

Step 3: Turn 'same pressure' into a symbol.
If the pressure does not change at all, then the change in pressure is zero. In symbols that is $\Delta P = 0$.

Step 4: Check the other options so we are sure.
$Q = 0$ means no heat goes in or out, which is an adiabatic process, not ours.

Step 5: Knock out two more.
$\Delta T = 0$ means the temperature stays fixed, that is an isothermal process. And $\Delta V = 0$ means the volume stays fixed, that is an isochoric process.

Step 6: Pick the survivor.
Only $\Delta P = 0$ keeps the pressure constant, so that is our isobaric condition.
\[ \boxed{\Delta P = 0} \]