Midterm 2 Flashcards
What is a projectile?
any object, not in contact with the ground that is allowed to move under the influence of gravity and no other external force.
What kind of path will an object in flight on earth follow?
Parabolic
symmetrical curve
When an object is not in contact with the ground what is its horizontal acceleration?
0 m/s^2
What is the optimal angle of release for height?
90 degrees
What is the optimal angle of release for distance?
45 degrees
What does the jump mat measure?
It measures time in the air and jump height
What does the force plate measure?
Measures the time in the air and calculates initial velocity
What does the Ipod measure?
Jump time, measures the period of time when the accelerometer doesn’t measure any force
What are Kinetics?
The concepts of mass, force, and energy as they affect motion.
What is Newton’s first law?
Law of inertia: an object at rest tends to stay at rest and an object in uniform motion tends to stay in uniform motion unless acted upon by a net external force
Explain the difference between static and dynamic equilibrium.
Static equilibrium is an object at rest with a net external force of 0 acting on it.
Dynamic equilibrium is an object in uniform motion with a net external force of 0 acting on it.
What is inertia?
an objects tendency to resist change in the state of motion
what is the equation for momentum?
P = mass x velocity
What is the law of conservation of momentum?
In the absence of external forces, the total momentum of a given system is conserved (is constant)
Pbefore = Pafter
What is the coefficient of restitution and what is it used for?
it is the absolute value of the ratio of the velocity of separation to the velocity of approach.
It is a means of quantifying how elastic the collisions are.
e = (Vbf - Vaf)/(Vai - Vbi)
What is the COR for a perfectly elastic collision?
1
What is the COR for a perfectly inelastic collision?
0
Provide the equation for elastic collisions.
MaVai + MbVbi = MaVaf + MbVbf
Provide the equation for inelastic collisions.
M1V1 + M2V2 = (M1+M2)Vcombined
What makes up the Combined Free Limb Relative Momentum?
CFLRM = Contralateral Arm RM + Ispsilateral Arm RM + Lead Leg RM
What is Newton’s Second law?
The law of acceleration
A force applied to a body causes an acceleration of that body of a magnitude proportional to the force, in the direction of the force, and inversely proportional to the body’s mass
What is Newton’s Third Law?
The Law of Reaction
Every applied force is accompanied by a reaction force, equal in magnitude and opposite in direction
What is impulse? Give the equation for it.
Impulse is a measure of a force applied for a certain amount of time.
I = Force x Time
I = change in momentum
What are two things that the change in the momentum of a system depends on?
1) The magnitude of external forces
2) The time over which the forces act
What is Friction?
The force resisting the relative motion of solid surfaces.
Dry friction
Fluid
Internal
What is the equation for the critical point of static friction?
F = mew x N
What are some characteristics of kinetic friction?
As Force applied increases,It remains constant and is always less than Force applied
For any incline of a certain angle, what are the equations you can use to find perpendicular, parallel, Normal, Friction
Fpd = mg x (Cos(angle))
Fpl = mg x (Sin(angle))
N = -mg x (Cos(angle))
Ff = -mg x (Sin(angle))
What is angular kinematics?
The study of motion of an object about a circular path exclusive of the influences of mass and force.
When does angular motion occur?
Angular motion occurs when all points on an object move in a circular path around the same axis
Describe absolute angular displacement
angular position of an object relative to a fixed position
Describe Relative angular velocity
angular position of an object relative to a plane or line that is capable of moving
In angular kinematics, what direction is considered negative and which is considered positive?
Clockwise = negative Counterclocwise = positive
Describe Centripetal Acceleration
if something is turning around a circle then it required an external force or acceleration to cause it to change direction
Centre seeking
What are the four main components of a signal?
Frequency, Amplitude, Off-set, Phase shift
What is it called when you convert a time-domain signal to a frequency-domain signal?
Fourier Transform
