Topic 2: Mechanics Flashcards
When can you use SUVAT equations?
When an object is moving at uniform acceleration
What is velocity?
Rate of change of displacement
What is acceleration?
Rate of change of velocity
What is uniform acceleration?
Uniform acceleration is when acceleration of an object is constant.
What does acceleration-time graph area show?
Area under shows change in velocity
What does velocity-time graph gradient/area show?
Gradient shows acceleration
Area shows displacement
What does displacement-time graph gradient show?
Gradient shows velocity
What is a scalar/vector quantity?
Scalar quantity only has a magnitude
Vector quantity has a magnitude and direction
How to resolve a vector?
TO resolve vector;
split vector into horizontal/vertical component
How to add vectors?
Position vectors in tip-to-tail
Use trig
How are projectile motion different to usual vectors?
Horizontal/vertical components are separate. Use different
Horizontal acceleration always 0.
What is a free-body force diagram?
Diagram which shows all forces that act on an object
What is newtons 1st law?
Newtons first law states that an object remains stationary or moves at a constant velocity unless a resultant force is experinced
What is Newton’s 2nd law?
Acceleration of an object ∝ resultant force
F = ma
What is terminal velocity?
Terminal velocity is when driving forces and resistive forces are equal. No acceleration; constant velocity
What is gravitational field strength?
Force per unit mass exerted by a gravitational field on an object
What is weight?
Weight is the gravitational force that acts due to an object’s weight
What is Newton’s 3rd Law?
Newton’s 3rd law states for each force experienced by an object, the object exerts an equal and opposite force.
What is momentum?
Products of mass and velocity
What does conservation of momentum state?
Momentum is always conserved in any interaction where no external forces act.
p before = p after
What is a moment of a force?
Force multiplied by perpendicular distance from line of action of the force to the point.
What does equilibrium in moments mean?
Moments CW = moments ACW
What is the centre of gravity in moments?
The point at which gravity appears to act
Where is the centre of gravity in uniform objects?
Centre
What is work done?
Force causing motion multiplied by distance travelled in direction of motion
What is kinetic energy?
Kinetic energy is energy that an object has due to its motion.
What is gravitational potential energy?
GPE is energy object has due to its position in gravitational field.
What does conservation of energy state?
Energy cannot be destroyed or created but transferred from one form to another.
Total energy in = total energy out
What is power?
Power is the rate of energy transfer
What is efficiency?
Measure of how efficiently a system transfers energy.
