Question

Is a slow process always isothermal? Is a quick process always adiabatic?

Answer 1

For an isothermal process, PV = K, where P is pressure, V is volume of the system and K is constant. In an isothermal process, a small change in V produces only a small change in p, so as to keep the product constant. On the other hand, in an adiabatic process, $P{V}^{\gamma }=k,\gamma =\frac{C_{\mathrm{P}}}{C_{\mathrm{V}}}$ > 1 is the ratio of heat capacities at constant pressure and volume, respectively, and k is a constant. In this process, a small increase in volume produces a large decrease in pressure. Therefore, an isothermal process is considered to be a slow process and an adiabatic process a quick process.