Unit 1 Review
Work
Energy
Power
Grab Bag
100
A vector quantity has ____ and ____.
What is magnitude and direction?
100
The formula and units for work.
What is W = F*d*cos(theta) and joules?
100
Energy is a scalar quantity because of this reason.
What is that energy has magnitude but not direction?
100
This is the formula for power.
What is work/time?
100
Newton's first law states this.
What is that an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force?
200
When an object is speeding up, its acceleration is going in what direction relative to its velocity (same or different directions?).
What is acceleration is in the same direction as the velocity?
200
Work is equal to the change in this type of energy.
What is kinetic energy?
200
If a block is dropped from a certain height above the ground, and energy is conserved, we know that the block's initial potential energy is equal to this.
What is the block's final kinetic energy?
200
This is the unit for power.
What is the Watt?
200
This is one example of potential energy besides gravitational potential energy.
What is elastic potential energy (Energy stored in elastic materials as the result of their stretching or compressing. Elastic potential energy can be stored in rubber bands, bungee chords, trampolines, springs, an arrow drawn into a bow, etc.). Also, magnetic potential energy.
300
Newton's third law states this.
What is that for every action, there is an equal and opposite reaction?
300
When a force acts on an object perpendicular to the object's displacement, this much work is done.
What is 0 J? (cos 90 = 0)
300
Increasing an object's kinetic energy can be done in these ways.
What is increasing the object's velocity or mass?
300
This is the type of quantity (vector or scalar) that power is.
What is a scalar quantity?
300
This is one example of a non-conservative force.
What is friction, tension, air resistance, normal force?
400
The amount of force needed to keep an object moving at a constant velocity.
What is 0 N.
400
If a force acts in the opposite direction of an object's motion, so that the force hinders the object's displacement rather than causing it, this type of work is done.
What is negative work?
400
Raising a book from the floor to above your head will change the energy of the book in this way. (Be able to explain your answer!)
What is it will increase the book's gravitational potential energy? (GPE = mgh)
400
If two identical jobs/tasks are done at different rates--one slowly and one quickly--this is how the work and the power of the two jobs compare (job 1 vs job 2).
What is work is the same, but power is different?
400
An object moving in a circle experiences an acceleration in this direction.
What is towards the center of the circle?
500
An object moving in uniform circular motion is moving in a circle with a uniform or constant speed, but it has an acceleration because of this.
What is the change in direction of the velocity? (Remember, velocity is a vector.)
500
A waiter carries a tray full of meals above their head by one arm straight across the room at constant speed. This is the amount of work done. (Must be able to explain answer!)
What is no work? (The force does not cause the displacement. To cause a displacement, there must be a component of force in the direction of the displacement.)
500
If the velocity of an object doubles, this is how much its kinetic energy will increase.
What is the kinetic energy will quadruple?
500
If the same amount of work is done by two motors, but the work is done in one second by motor one and in five seconds by motor two, this is the motor with the greater power.
What is motor 1?
500
If the work done on an object is independent of the path taken by the object, the force acting on the object is this type of force.
What is a conservative force?
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