Physics Quiz about work

Work is

the result of a force changing the displacement of an object and change in energy

What are the equations that are equal to work?

FDcos(theta)

deltaKE = 1/2m(vf² +vi²)

What is Kinetic energy?

energy of motion

1. ANYTHING that has a non-zero velocity

Units for KE

Joules (J)

KE equation

½ m(v)²

Can you have negative kinetic energy?

No

What is theta in the work equation?

θ is the angle between the force and the direction of the displacement

If the angle between the force and displacement is 90 degrees, how much work is being done?

O J

KE depends on

how fast the motion is

PE is

energy that is being stored in an object because of its position

GPE is

is energy that is stored as a result of someone’s vertical displacement OR height above the surface of the earth/a zero point surface (for ex: the floor, the table)

Equation of GPE is

mgh

GPE units is

Joules

EPE is

energy stored as a result of a spring being stretched or compressed

EPE equation is:

1/2kx²

^{k = spring constant}

^{x =}  displacement from equilibrium position

KPE units

Joules

Mechanical Energy is

The ability of an object to do work based on its kinetic and potential energy

Is kinetic energy a type of Mechanical Energy?

Yes

Is potential energy a type of Potential energy?

Yes

Total Mechanical Energy (TME):

is the sum of an object’s potential and kinetic energies.

TME DISCLAIMER

TME is conserved (constant) when gravity and/or spring force are the only forces acting in the system.

TME is going to stay the same throughout the whole system

Work and KE connection?

Work is the change in Kinetic Energy

Power is

the rate at which work is being done

Power equation:

P = Fd/t 

P = Fv

Power units

Watts