Unit 5- Physics Flashcards
What is brittle?
Is how likely something is to crack, shatter when shocked
What is strength?
How easily something breaks under pressure
What is malleable?
How easily something is formed by being rolled into thin sheets
What is ductile?
How easily something can be drawn into thin wires
What is Hooke’s law?
The relationship between force and extension is directly proportional
What is elastic energy?
The work done to an elastic object that has been stretched or compressed
What is the equation for change in energy? ( In terms of force)
1/2 x Force x Displacement
What is the equation for change in energy? ( In terms of spring constant)
1/2 x spring constant x(displacement)2
What is stress?
Measure of the force acting within a material
What is strain?
The extension of the object compared to its original length
What is young’s modulus?
A constant of proportionality that shows the stiffness of the material
What is the equation for young’s modulus?
Stress/strain
What is the equation for Stress?
Force/area
What is the equation for Strain?
Change in length/ original length
What is creep?
When a material under stress deforms gradually over time.
What is fatigue?
The embrittlement and failure of a material due to cycles of low stress levels
What is elastic hysteresis?
The energy required to load the material with stress is different to the energy required to unload the material of stress.
What is density?
The mass per unit volume
What is the equation for density?
Mass divided by volume
What is the equation for the standard enthalpy change of a reaction?
sum of (products) - sum of (Reactants)
What is a laminar flow?
Streamlines do not cross
What is turbulent flow?
Streamlines cross that forms vortices and eddy currents
What will happen to the viscosity of a non-newtonian fluid?
It is constant at any given temperature
What will happen to the viscosity of a newtonian fluid?
It will change under different forces
What is mass flow rate?
Mass of fluid flow per second for all points along a pipe or stream tube is constant
What happens to the velocity if the cross sectional area increases?
Decreases
What is pressure?
Force applied over a given area.
What happens to the pressure if the velocity increases?
Pressure Decreases
What happens to the pressure if the area increases?
Pressure increases
What is Bernoulli’s principle?
At points along a horizontal streamlines, higher pressure regions have lower fluid speed and lower pressure regions have higher fluid speed.
What is the quantity symbol for Power?
P
What is the quantity symbol for Work done?
W
What is the quantity symbol for Force?
F
What is the quantity symbol for Volume?
V
What is the quantity symbol for Distance?
x
What is the quantity symbol for Pressure?
p
What is the quantity symbol for Temperature?
T
What is the unit for Power?
Watts
What is the unit for Work done?
Joules
What is the unit for Force?
Newtons
What is the unit for Volume?
Metres cubed
What is the unit for Distance?
Metres
What is the unit for Pressure?
Pascals
What is the unit for Temperature?
Degrees celsius
What is the equation for work done in terms of Force?
Force x change in distance
What is the equation for work done in terms of Pressure?
Pressure x change in volume
What is the equation for Efficiency?
Useful energy output/ total energy input
What is the definition for temperature?
Average kinetic energy of particles
What is the definition of heat?
Amount of thermal energy transferred by a given process
What is a heat engine?
Machines designed to convert thermal energy into useful mechanical work.
What is the conservation of energy law?
Q out + W out
What is specific heat capacity?
The energy required to increase the temperature of 1kg of a substance by 1 kelvin
What is the equation for input energy in terms of change in temperature?
Mass x specific heat capacity x change in temperature
What happens to the temperature during a state change?
Stays the same
What are the properties of an ideal gas?
- Collisions between particles are elastic
- Particles do not attract or repel each other
- Particles are negligibly small compared with the volume that the gas is occupying
What is the first law of thermodynamics?
The change in internal energy of a system is equal to the heat energy input minus the output work done
What is the second law of thermodynamics?
The second law identifies that a natural process can never be fully reversed and it is impossible to completely change all heat into work.
What is the Zeroth law of thermodynamics?
When two systems are in thermal contact, but there is no net transfer of heat because they are at the same temperature.
What is the isothermal process?
heat transfer that takes place at a constant temperature
What is the Adiabatic process?
work is done but there is no transfer of heat.
