Physics Definitions Mechanics

HideShow resource information
Acceleration
Rate of change with time of velocity vector. Magnitude given by gradient of graph of v against t
1 of 28
Centripetal Force
Name of any force or resultant of individual forces that point towards centre of a circular path
2 of 28
Centripetal Acceleration
Acceleration due to a changing velocity direction. Points towards centre of circular path =v²/r
3 of 28
Displacement
Distance in a given direction from a fixed origin, is a vector
4 of 28
Efficiency
Ratio of useful output work to input work
5 of 28
Energy Conservation
Energy cannot be destroyed or created, it can be transformed from one form to another. The mechanical energy of a system stays the same in absence of frictional forces
6 of 28
Equipotential Surface
Set of points that have same gravitational potential
7 of 28
Escape Speed
Minimum speed an object must have at the surface of a planet so that it can move an infinite distance away (escape its field) =√2GM/r
8 of 28
Gravitational Field Strength
Gravitational force experienced by a point particle of unit mass. The field strength due to spherical or point mass M is g=GM/r²
9 of 28
Gravitational Potential
Work done in bringing a point particle of unit mass from infinity to a point in a gravitational field v=-GM/r (scalar)
10 of 28
Gravitational Potential Energy Difference
Work must be done in order to raise mass m by a vertical distance h Eg=mgh
11 of 28
Gravitational Potential Energy of 2 Point Masses
Work done in moving 2 point masses M and m, which are infinitely far apart initially until they are separated by a distance r. Eg=-GMm/r
12 of 28
Hooke’s Law
The tension in a spring is proportional to its extension and opposite to it
13 of 28
Impulse
The total change in the momentum of a system as a result of a force acting on it. Its magnitude is given by the area under a force versus time graph. (vector)
14 of 28
Law of Gravitation
There is an attractive force between any 2 point masses, given by =G (m₁m₂)/r^2 , r is their separation. Directed along line joining masses.
15 of 28
Momentum Conservation
If the net external force on a system is zero, the total momentum of the system stays the same
16 of 28
Newton’s First Law
If the net external force on a system is zero, the system remains at rest or moves with constant velocity
17 of 28
Newton’s Second Law
The net force on a body equals the rate of change of the body’s momentum. When the mass is constant this is F=ma
18 of 28
Newton’s Third Law
If a body A exerts a force on body B, then body B will exert and equal and opposite force on body A
19 of 28
Orbit
The path of an object when under the influence of just the force of gravitation
20 of 28
Orbital Speed
The speed of a body in orbit v=√(GM/r)
21 of 28
Power
The rate at which work is being performed P=W/t (scalar)
22 of 28
Translational Equilibrium
The state of a system where the net external force is zero
23 of 28
Velocity
The rate of change with time of the displacement vector. Gradient of a graph of displacement versus time (vector)
24 of 28
Weight
The force of gravitation on a body. Refers to gravitational force on a small body due to a large body such as a planet
25 of 28
Work (Mechanical)
The product of the force times the distance moved by its point of application in the direction of the force. It is given by the area under the graph of force versus distance (scalar)
26 of 28
Work Done in Gravitational Field
Work done in moving a mass from one point to another in a gravitational field W=mV. Independent of path followed
27 of 28
Work-Kinetic Energy Relation
The net work done on a body (sum of work done by individual forces) equals change in kinetic energy of the body
28 of 28

Other cards in this set

Card 2

Front

Name of any force or resultant of individual forces that point towards centre of a circular path

Back

Centripetal Force

Card 3

Front

Acceleration due to a changing velocity direction. Points towards centre of circular path =v²/r

Card 4

Front

Distance in a given direction from a fixed origin, is a vector

Card 5

Front

Ratio of useful output work to input work