Lesson: Combined Variation Mathematics
In this lesson, we will learn how to write an equation to describe combined variation and how to use proportions to find other sets of values.
Sample Question Videos
We know that varies directly with and inversely with . Given that when and , find the value of when and .
When one inflates a balloon, the pressure of gas inside the balloon varies directly with the quantity of gas injected inside (the unit for this is moles), and the pressure varies inversely with the volume of the balloon (which increases when the balloon expands). Assume that the temperature of the gas inside the balloon is constant.
Write an equation for the pressure of gas inside the balloon () in terms of the quantity of gas inside the balloon () and the volume of the balloon (). Let be a constant.
Given that the pressure inside the balloon is 1.1 bars with 0.089 moles of air inside the balloon of volume 2 dm3, find the pressure inside the balloon when there are 0.24 moles of air and its volume is 4 dm3. Round your answer to one decimal place.
In an electric circuit, the current intensity going through a resistor varies directly with the voltage drop across the resistor and inversely with the resistance . Given that the current intensity is 2.5 A with a voltage drop of 5 V across a resistor of resistance 2 Ω, find the value of the current intensity when the voltage drop is 15 V and the resistance is 3 Ω.