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Vocabulary
SI Units
Practice Problems
Formulas
100

Define Work

the transfer of energy to a body by the application of a force that causes the body to move in the direction of the force; it is equal to the product of the magnitude of the component of a force along the direction of displacement and the magnitude of the displacement

100
Define the SI unit for Work

Joules (J)

100

A person lifts a 4.5 kg cement block a vertical distance of 1.2 m and then carries the block horizontally a distance of 7.3 m. Determine the work done by the person and by the force of gravity in this process

53 J,-53 J

100

Define the formula for Work

W=Fdcosθ

200

Define Kinetic Energy

the energy of an object that is due to the object's motion

200

Define the SI unit for Force

Newton (N)

200

When catching a baseball, a catcher’s glove moves by 10 cm along the line of motion of the ball. If the baseball exerts a force of 475 N on the glove, how much work is done by the ball?

47.5 J

200

Define the formula for the Work-Kinetic Energy Theorem

Wnet = ΔKE

300

Define Gravitational Potential Energy

the potential energy stored in the gravitational fields of interacting bodies

300

Define the SI unit for Displacement

Meter (M)

300

What is the kinetic energy of an automobile with mass of 1250 kg traveling at a speed of 11 m/s?

7.6×104J

300

Define the formula for Kinetic Energy

KE=1/2(ms2)

400

Define Work Kinetic Energy Theorem

the theorem that states that the change in kinetic energy of a moving particle is equal to the work done by all of the forces acting on the particle

400

Define the SI unit for Gravitational Potential Energy 

Joules (J) per Kilogram (kg)

400

A child and sled with a combined mass of 50.0 kg slide down a frictionless hill that is 7.34 m high. If the sled starts from rest, what is the mechanical energy of the system, and what is the sled’s speed at the bottom of the hill?

3600 J; 12.0 m/s

400

Define the formula for Elastic Potential Energy

PEelastic=1/2(kx2)

500

Define Potential Energy

the energy that an object has because of the position, shape, or condition of the object

500

Define the SI unit for Power

Watt (W)

500

If an automobile engine delivers 50.0 hp of power, how much time will it take for the engine to do 6.40 × 105 J of work? (Hint: Note that one horse- power, 1 hp, is equal to 746 watts.)

17.2 s

500

Define the formula for Conservation of Mechanical Energy

MEI=MEF