5. Work Energy Power Flashcards
What is work?
work is the transfer of energy, or process of energy conversion
What is work done?
work done by a constant force on an object is the product of the force and the displacement in the direction of the force.
What is the formula of work done?
W=Fs or W=Fs cosϴ
What is Kinetic Energy?
kinetic energy is defined as the stored ability of an object to do work as a result of its motion.
What is the formula of kinetic energy?
Ek = 1/2 mv²
What is work-energy theorem?
work done by net force on body = change in kinetic energy of body
What is the relation between net work done and kinetic energy?
If net work done is positive, the object will gain kinetic energy. vice versa
What is potential energy?
Potential energy is defined as the stored energy of an object to do work as a result of its position or shape
What is the S.I units of energy?
joules (J)
What is the formula for Gravitational potential energy (near the surface of earth)
U= mgh
What is the principle of conservation of energy?
The principle of conservation of energy states that energy cannot be created or destroyed, but it an be converted from one form to another.
What is the equation of conservation of mechanical energy?
loss in KE = gain in PE
What is the equation of conservation of energy in presence of dissipative forces?
KE initial + PE initial = KE final + PE final + work done against dissipative forces
What is Power?
Power is the work done per unit time
What is the formula of power, instantaneous power and average power?
power = work done / time (W/t)
instantaneous power = instantaneous force x instantaneous velocity (Fv)
average power = total work done / total time
