PHYS 165 Module 4 - Physics Flashcards & Exam Questions with Answers
Work the process of producing change in the environment
Work any force causing an action over a distance changes the energy
(Energy transfer when a force causes displacement)
The more force applied and additionally, the further an the more work is done
object is moved,
Work equation W = Fdcos(θ)
What is the symbol for Work and what is it measured in? W
Joules (J)
What does each symbol stand for in the work equation? F: force (Newtons, N)
d: the displacement of the system (meters, m)
θ: angle between force (F) and displacement (d)
W: work (Joules, J)
1 Joule = 1 1N X m
Is work a scalar or vector? Scalar
(that means there is no direction for work. Work can be positive, negative, and even
zero)
When is work maximum? When force is parallel to the displacement
(θ = 0° → cos(0)=1 → W = Fd)
When is work zero? F=0
d= 0
Force ⟂ displacement (θ = 90° → cos(90)=0)
Energy the ability to do work
(the ability to produce change in the environment or change in the system itself)
When the work is positive and moving in the same the energy of the system is being increased.
direction as the displacement,
When work is negative and moving in the opposite the energy of the system is being decreased
direction as the displacement,
When work is zero, .... there is no change in the energy of the system due to that force.
, PHYS 165 Module 4 - Physics Flashcards & Exam Questions with Answers
Power The rate of doing work or transferring energy
Units for power Watts (W) and the secondary unit is horsepower (hp)
1 hp = ? W 746 W
1 W = ? J/s 1 J/s
Equation for Mechanical power (work form) P = W/delta t
What are the variables for the mechanical power equation? P = power going into the system
W = the mechanical work done on the system
delta t = time interval
Power equation for power going into the system (energy P = delta E/ delta t
form)
What are the variables for the general power equation? P = power going into the system
delta E = the change in energy of the system
delta t = time interval
What does "more powerful" mean? Doing more work in less time
Power with force + velocity (constant velocity form) P = Fv
Types of Energy Mechanical, Chemical, Thermal, Electromagnetic
2 Forms of Energy Mechanical energy and nonmechanical energy
Mechanical energy the energy d/t a system's motion, position, or condition that can cause motion
Non-mechanical enrgy Not associated with a systems' position, condition, or motion
ex: heat, light, sound, nuclear, electric, magnetic
Two Forms of Mechanical Energy Kinetic energy and potential energy
Work the process of producing change in the environment
Work any force causing an action over a distance changes the energy
(Energy transfer when a force causes displacement)
The more force applied and additionally, the further an the more work is done
object is moved,
Work equation W = Fdcos(θ)
What is the symbol for Work and what is it measured in? W
Joules (J)
What does each symbol stand for in the work equation? F: force (Newtons, N)
d: the displacement of the system (meters, m)
θ: angle between force (F) and displacement (d)
W: work (Joules, J)
1 Joule = 1 1N X m
Is work a scalar or vector? Scalar
(that means there is no direction for work. Work can be positive, negative, and even
zero)
When is work maximum? When force is parallel to the displacement
(θ = 0° → cos(0)=1 → W = Fd)
When is work zero? F=0
d= 0
Force ⟂ displacement (θ = 90° → cos(90)=0)
Energy the ability to do work
(the ability to produce change in the environment or change in the system itself)
When the work is positive and moving in the same the energy of the system is being increased.
direction as the displacement,
When work is negative and moving in the opposite the energy of the system is being decreased
direction as the displacement,
When work is zero, .... there is no change in the energy of the system due to that force.
, PHYS 165 Module 4 - Physics Flashcards & Exam Questions with Answers
Power The rate of doing work or transferring energy
Units for power Watts (W) and the secondary unit is horsepower (hp)
1 hp = ? W 746 W
1 W = ? J/s 1 J/s
Equation for Mechanical power (work form) P = W/delta t
What are the variables for the mechanical power equation? P = power going into the system
W = the mechanical work done on the system
delta t = time interval
Power equation for power going into the system (energy P = delta E/ delta t
form)
What are the variables for the general power equation? P = power going into the system
delta E = the change in energy of the system
delta t = time interval
What does "more powerful" mean? Doing more work in less time
Power with force + velocity (constant velocity form) P = Fv
Types of Energy Mechanical, Chemical, Thermal, Electromagnetic
2 Forms of Energy Mechanical energy and nonmechanical energy
Mechanical energy the energy d/t a system's motion, position, or condition that can cause motion
Non-mechanical enrgy Not associated with a systems' position, condition, or motion
ex: heat, light, sound, nuclear, electric, magnetic
Two Forms of Mechanical Energy Kinetic energy and potential energy
