Final answer:
When the pressure difference across a capillary tube is increased, it generally results in an increased flow of refrigerant, following the principles of the continuity equation and Bernoulli's equation. option B is the correct answer.
Step-by-step explanation:
When the pressure difference across a capillary tube is increased, several things can happen depending on the context and the specific system in question. In general, an increased pressure difference indicates that there is more force driving the flow. According to principles like Bernoulli's equation, if the kinetic energy per unit volume of a fluid increases while pressure is constant, it implies that potential energy per unit volume of the fluid decreases. However, when the channel through which a fluid flows narrows, the fluid is forced to speed up - this is due to the continuity equation, which states that the product of cross-sectional area and velocity of the flow is constant. As a result, where the tube narrows, the pressure typically decreases. So, in response to the question, the most likely answer would be that the flow of refrigerant increases.
When the pressure difference across a capillary tube is increased, the flow of refrigerant decreases. This is because increasing the pressure difference across the capillary tube causes the capillary to constrict, which restricts the flow of refrigerant. The decrease in flow rate is due to the increase in pressure of the refrigerant.
Therefore, the correct answer is b. The flow of refrigerant decreases.