Module 5 Part 1- Newtonian World Flashcards
What is a radian
A radian is a measurement of angles. 1 radian is the angle encompassed by the sector of a circle with three equal sides a.k.a the arc is of length r
How many radians in a circle and what is a radian equal to
There are 2π radians in a circle and as there are 360° in a circle 1rad=57.3 approx.
What are the two equations for linear velocity
V=(2πr)/T or V=2πrf
What is angular speed and how does it differ from linear velocity
Angular speed is the angle swept per second and it stays constant as an object undergoes circular motion as it is the magnitude of velocity which is the tangent to the circle at any given point therefore constantly changes
What is the equation for angular speed and the units
ω=Δθ/Δt measured in radians/second or rads^1
What else can angular speed me measured in and how do you convert?
It is more commonly measured in revolutions per second or minute and can be converted by considering that 1 revolution (360°)=2π so you can multiply by 2π
What is angular frequency
Angular frequency is essentially the same as angular speed however it is a way to relate the frequency to the speed through the equation: ω=2πf or 2π/T
Explain acceleration of an object in circular motion
If an object is traveling in a circle then the speed is the same but the velocity changes due to change in direction therefore there is an acceleration-this is called centripetal acceleration
What is the relationship between angular speed and linear velocity
v=wr or w=v/r
What is the equation for centripetal acceleration
a=vw or a=v^2/r or a=w^2r
What is centripetal force
Centripetal force is the name given to any force which acts towards the center of a circle e.g:rope on a mass or gravity on a planet
What are the two equations for centripetal force and how do you arrive there
By using F=ma you can sub in the equations for centripetal acceleration to get:
F=(mv^2)/r or F=mrw^2
What is the equation for centripetal force in a pendulum
Wcosθ=Tension=centripetal force ((mv^2)/r or mrw^2)
What are the two rules of simple harmonic motion
Acceleration of an object is towards the a center therefore displacement is opposite to the acceleration.
Acceleration is proportional to the displacement
What is equation in SHM for acceleration
A= -w^2x
What are the two equations for displacement in an oscillating system
x=Acos(wt) and x=Asin(wt)
When do you use each displacement equation in SHM
Acos(wt) is used when the displacement is maximum at the start
Asin(wt) is used when the displacement is zero at the start
What is the equation for maximum velocity for oscillations and briefly explain
V=wA as cos(wt) or sin(wt) will be equal to one as velocity is the highest it can be so they will disappear from the equation
What is resonance
Resonance is the tendency of a system to oscillate with at ever increasing amplitudes when the frequency of the driving force is equal to the natural frequency
When does resonance occur
Resonance occurs when the external force is periodically in phase and timed correctly with the natural frequency of vibration
What is natural frequency of vibration
It is the frequency for a given object which will cause it to vibrate at an exponentially increasing amplitude
What is damping and what is the effect
Damping is when the external force is applied too early or too late and it causes the amplitude to decrease and the input frequency to also decrease
What is thermal contact
When energy can be exchanged between two bodies in contact with each other due to a difference in temperature
What is thermal equilibrium
When two bodies to not exchange any energy even in thermal contact due to them being at the same temperature
What is the zeroth law of thermal dynamics
Thermal equilibrium is dependent on one property: temperature
What is the first law of thermodynamics
Energy cannot be created or destroyed, it can only be re distributed or changed form
What is the second law of thermal dynamics
The entropy of a system not in thermal equilibrium almost always increases
What is the third law of thermodynamics
The entropy of a system approaches a constant value as the temperature approaches absolute zero
What is entropy
Entropy is a measure of the disorder of a system or the degree of randomness of the system
An assumption in kinetic theory is that molecules are
Points with negligible volume (compared to the volume of gas)
An assumption in kinetic theory is that molecules do not
Attract one another
An assumption in kinetic theory is that molecules move
In constant random motion
An assumption in kinetic theory is that all collisions made
Perfectly elastic
An assumption in kinetic theory is that the time taken for a collision is
Much less than the time between collisions
An assumption in kinetic theory is that any sample of an ideal gas
contains a very large number of molecules
What is brownian motion
Random motion of microscopic particles in a fluid that results in random collisions
What is internal energy of a substance
The sum of the randomly distributed kinetic and potential energies of atoms or molecules within the substance
What can internal energy be affected by and explain
Temperature-the particles will move around more and have more kinetic energy
Change of state-the electrostatic potential energy changes
What is specific heat capacity and what is the equation for it
The amount of energy it takes per unit mass to change the temperature by 1K (or °C)
E=mc∆θ
What is specific latent heat and what is the equation for it
The amount of energy to change the state per unit mass
E=mL
What is specific latent heat of fusion
The specific latent heat for the solid/liquid change in state
What is specific latent heat of vaporisation
The specific latent heat for the liquid/gas change in state
What is the difference between forced and free oscillations
Free-no external forces
Forced-a periodic driving force makes it oscillate at a particular frequency
