Work-Energy Theorem
Work done by a constant force
What is W = Fdcos(theta)
Equation of force
What is -du/dx?
Gravitational potential energy is calculated by using the formula
What is U = mgh?
Law of conservation of energy definition
What is that energy cannot be created or destroyed, only transferred or converted from one form to another?
The definition of power
What is the rate at which work is done?
Definition of kinetic energy
What is 1/2(m)(v^2)?
Hooke's Law equation
What is F=-kx?
True or false: Potential energy increases as height increases
What is True?
Equation of conservation of energy
What is Ui+Ki=Uf+Kf?
The equation of power
What is the change in W divided by the change in time?
If the force and displacement do not have a component in this direction then no work is done
What is parallel?
When force being applied is paralell to displacement, drop this in Work equation
What is the dot product?
What is -(integral) F * dx?
Definition of nonconservative forces
What is one for which work depends on the path taken?
The unit of power in SI units
What are watts?
The total mechanical energy of a system conserved when:
I. Always
II. When nonconservative forces are present but do not do work.
III. When nonconservative forces are not present.
What are II. and III.?
True or false: Force is the derivative of potential energy
(Force is the negative derivative of potential energy)
True or false: Potential energy is movement energy? If false, it is really this type of energy...
What is False and stored energy?
Equation of non-conservative forces
A 2 kg mass is moving in one dimension with a velocity given by v(t)=1/2t^2. At t=4s, the instantaneous power delivered by the net force is
What is P=64 watts?
A 10 kg mass is moving at 5 m/s over a rough surface. A 50 N horizontal tension force causes it to accelerate to 8 m/s while travelling 6 m. The coefficient of kinetic friction between the mass and the surface is
What is 0.18?
When work is parallel to direction of motion, Work =
What is 0?
A 125 kg person holding a sack that weighs 25 kg stands on a rooftop that is 15 meters tall. The potential energy of this person and sack is
What is 22,500 J?
Starting from rest, a skateboarder travels down a 25 degree incline that's 22m long. Using conservation of energy, the skateboarder's speed when he reaches the bottom is... (Ignore friction.)
What is 13.5 m/s?
(U1=K2
mgh=12mv^2
Solve for v.
v=√2gh
h=22sin(25).
v=√2(9.8 ms2)(22)(sin(25))
v=13.5 ms
9 reindeer moving at a constant velocity carry a 10,000 kg sleigh across Springfield (a distance of 200 km) in 1 hr. The 9 reindeer can generate this much power
What is 0?