Pressure Flashcards
(13 cards)
What is temperature in gas dependant on?
The amount of energy in the kinetic energy stores in the gases molecules.
What happens if you increase the temperature of a gas in a fixed volume?
The pressure increases because the molecules will move faster (due to having more kinetic energy) and collide with the container more often.
What happens if you increase the volume containing a gas at a constant temperature?
The pressure decreases because the speed of the molecules remains the same yet the distance between each collision decreases which means there are less collisions overall.
What happens when work is done on a gas?
The work done transfers energy to the gas which increases the internal energy which can increase the temperature.
Why does the temperature of a gas in a bike wheel increase when using a bicycle pump?
Work has to be done to overcome the pressure already in the tire so that new air particles can enter this causes the internal energy of the air to increase and so the temperature also increases.
How is force applied in fluids?
In fluids (liquids and gases), pressure is gained by applying force to a surface.
What is pressure like along a horizontal line in a fluid?
The pressure is the same at all horizontal points within the same fluid.
How do hydraulic systems transfer force?
In a closed hydraulic system, the pressure is the same all throughout the incompressible fluid. This allows forces to be transferred from one end of the pipe to the other, by varying the size of the input and output pistons the force can be multiplied.
How does upthrust work in a fluid?
A partially (or fully) submerged material experiences greater pressure on the bottom in the water than the top surface which causes there to be an upward force called upthrust.
How do you determine an object’s upthrust?
We can find the upthrust by calculating the difference in pressure between the top and the bottom of the object.
Why do objects float in fluids?
An object floats if it’s weight is less than the weight of the volume of water it has displaced.
What happens to density as you get higher in our atmosphere?
The atmosphere is a thin layer of gases surrounding the earth and as your altitude increases, the pressure decreases.
Why does pressure decrease as you get higher in our atmosphere?
As your altitude increases, the amount of air particles decreases and so this means there are less collisions happening. Since there are less collisions there is less pressure.
