A _____________is a combination of two or more simple machines.
What is a compound machine
100
____________is the ability to cause change.
What is energy
100
The _______ ____ _______________ ____ ___________ states that energy cannot be created or destroyed.
What is law of conservation of energy
100
During energy transformations, energy is never ________.
What is created or destroyed
200
A _________can change the speed, direction, and magnitude of a force.
What is a machine
200
The unit of work is the________
What is the Joule
200
A _________ is anything around you in which you can imagine a boundary.
What is a system
200
____________ _________is the sum of the kinetic energy and potential energy of the objects in a system.
What is mechanical energy
200
As energy transformations occur within a system, the total energy of the system remains ___________
What is constant
300
_______________is the ratio of the output force to the input force.
What is mechanical advantage
300
A _____________is a device that changes the force or increases the motion from work.
What is a machine
300
__________ ___________ is energy due to motion.
What is kinetic energy
300
A homerun is hit 430 feet to left field. The GPE is greatest at what point in the ball's flight?
What is the top of it's ascent when weightlessness occurs
300
A roller coaster is at the top of a hill and rolls to the top of a lower hill. If mechanical energy is constant, then on the top of which hill is the kinetic energy from the roller coaster's motion greater?
What is the top of the lower hill
400
___________is the ratio of output work to input work
What is efficiency
400
__________ __________ ________is energy that is stored by compresing stretching an object.
What is elastic potential energy
400
__________ is the rate at which energy is converted
What is power
400
Calories that you need for different activities depends on 3 things. Name 2
What are weight, body type, and degree of physical activity
500
A couch is pushed with a horizontal force of 80N and moves a distance of 5 m across the floor. How much work is done in moving the couch?
What is 400 J
500
A crate weighs 950 N. If you can use a pulley system to lift that crate with a force of only 250 N, then what is the mechanical advantage of the pulley system?
What is MA = 3.8
500
A 4.0 kg ceiling fan is placed 2.5 m above the floor. What is the gravitational potential energy of the Earth-ceiling fan system relative to the floor?
What is 98 J
500
You transform 950 Jof chemical energy into mechanical energy to push a sofa. If it took you 5.0 s to move the sofa, what is your power?
What is 190 W
500
What are three ways that simple machines can make work easier?
What is change in force direction, increasing speed, and increasing force