Ch.12 pt 2 Flashcards
From a mechanical standpoint, __ defined as force applied against a resistance, multiplied by the displacement of the resistance in the direction of the force.
Work
In mechanics, __ refers to the amount of mechanical work performed in a given time.
Power
What is the unit of power?
Watt
What is the unit of power?
Watts
Kinetic energy is?
energy of motion
Potential energy is?
energy of position
What are formulas for power?
P=Fv
P=Force x distance/ change in time
What does 1 watt equal to?
1 J/s
What is the unit of mechanical energy?
Joule
What is “k” in the formula for strain energy?
spring constant
What is “x” in the formula for strain energy?
distance over which the material is deformed
The law of conservation of mechanical energy states that when gravity is the only acting external force, a body/s mechanical energy __ __.
remains constant
__ __ is the capacity to do work by virtue of a deformed body/s return to its original shape.
Strain energy
What is true about the principle of work and energy?
The work of a force is equal to the change in energy that it produces in the object acted on
What is the formula for the law of conservation of mechanical energy?
(PE+KE)=C
Calculate the kinetic energy of a 500kg rollercoaster that is moving with a speed of 15 m/s
56250 J
Richard lifts a 300kg boulder and places it at an elevation of 2m. The boulder’s potential energy at the point is __.
588.6 J
What is the formula for the principle of work and energy?
W= changeKE + changePE + changeTE
A 25kg ball rolling with a velocity of 18 m/s has a kinetic energy of __.
4050 J
When a 40kg bar is elevated to a height of 3m, the potential energy at that point is __.
1177.2 J
