Dynamic and Statics Flashcards
Newton’s first law of motion is defined as
Inertia, and object in motion will stay in motion and an object at rest will stay at rest if the net outside force is zero
Newton’s second law of motion is defined as
Net force= Mass * acceleration
Newton’s third law of motion is defined as
An object that acts on another object with Force A will receive an equal and opposite reaction force from that object Force B
What is friction
The equation?
Friction is define by mew * normal force where mew is the friction constant
Friction opposes motion
what is static friction
It is the friction that is equal to the applied force that keeps the object at rest
What is kinetic friction
It is the friction that opposes movement, to calculate it you would use the equation.
What does it mean to be in mechanical equilibrium
To be in mechanical equilibrium the net force in the x and y have to be zero and the net rotational force has to be zero
What is the force of gravity on a ramp equivalent to
mgsintheta
What is the net force on an object sliding down a ramp with friction? Without friction?
friction, -mgsintheta+Friction
Without friction, -mgsintheta
What is the net force on an object sliding up a ramp with friction vs without friction
Friction: -mgsintheta-friction
Without: -mgsintheta
What is torque
what direction is torque negative? Positive?
Torque is the tendency of a force to cause rotational motion
Clockwise is negative, counter-clockwise is positive
What is the equation for torque
T= r F sin theta
T= r F perpendicular
On the left side of a seesaw a block with mass A sits on seat A. The plank of the seesaw is length L and the pivot point length M away from seat A which is closer. (pivot point is closer to seat A). Seat B is length N away from the pivot point.
M<N
How would you solve to problem to find how much mass B must be so that the seesaw is balanced.
When it is balance T=0
Set the point of reference at the pivot point
0= -M * MassA(9.8) + N * MassB(9.8)
Apply F= Ma
If an object is moving at a constant velocity, what is the net force? Why is this so?
The net force=0
Moving at constant velocity means there is zero acceleration.