P1 Fc Before Exam Flashcards
Give an equation linking spring constant and frequency
F= 1/2pi x square root of(k/m)
Give an equation for energy using Amplitude and spring constant
E=1/2 x K x A^2
Explain why an astronaut feels weightless in a space vehicle
Because the astronaut in the space vehicle are travelling at the same speed and there is no normal reaction force between the astronaut and the space vehicles floor
What mechanisms can we use to have an accurate experiment for determining acceleration of free fall
Using a trapdoor
And an electromagnet and light gates
What is drag
The frictional force for an object travelling through a fluid
Definition for centre of mass
A single point of an object that the whole weight is considered to act through
Describe the velocity against time graph for terminal velocity /when an object reaches maximum velocity
A decreasing gradient from 0 which flattens out
Describe the acceleration against time graph for terminal velocity
Acceleration at max when t=0 this decreases exponentially and reaches 0
When will an object float in a liquid
When the object has a lower density than the fluid
Definition for upthrust
The weight of fluid displaced by an object when it is submerged
State archimedes principle
When a body is partially or fully submerged in a fluid it will experience an upthrust equal to the weight of fluid it has displaced
State principle of moments
The sum of the acw moments = the sum of the cw moments
What is a couple
A pair of forces of equal size which act parallel to eachother but in the opposite direction
Def for moment and torque
Moment = the force times the perpendicular distance from the pivot to the line of action of the once
Torque= the size of one of the forces in a couple x the perpendicular distance between the forces
Def for work done
The force causing motion x the distance moved in that direction
How can we find the work done from a force extension graph
Work done = area under force-extension graph
Work done = elastic potential energy
What is the area under a stress-strain graph
Gradient = young modulus
Are = elastic potential energy per unit volume
Give equation for impulse
Impulse= change of momentum
Impulse= f x change in time
What is the area under under a force time graph equal to
Impulse ( change in momentum)
What is conserved in elastic and in elastic collisions
Elastic- KE and momentum
In elastic - momentum
State Newton’s second law
The resultant force is directly proportional to the rate of change of momentum
State newtons 1st law
An object will remain in equillibrium unless a resultant force acts on the object
How is the absolute temp scale different to the Celsius scale
It does not depend on the property of any specific material , Celsius scale uses the boiling and freezing points of water
Explain the structure of a gas liquid and solid
Gas- particles are free to move around with constant random motion no forces of attraction between particles
Liquid- particles constantly moving and free to move past eachother but are attracted to eachother
Solid- particles vibrate about fixed positions held by strong attractive forces
Explain thermal equillibrium
Thermal energy is transferred from a higher temp to regions of lower temp until all regions are in equillibrium
Def of specific heat capacity
The amount of energy needed to raise the temp of 1kg of substance by 1 K
