Mechanical Energy

Question 1

what is work = to?

Answer 1

W = [F] • [d]

1N • 1m = 1J

Question 2

What makes up mechanical energy

Answer 2

Kinetic Energy

Potential Energy

Question 3

Isolated system

Answer 3

A system that does not experience:

• applied force
• friction
• air resistance (drag)

E = E_K + E_G = constant

∆E = 0

Question 4

Non-isolated system

Answer 4

A system that DOES experience:

• applied force
• friction
• air resistance (drag)

∆E = W (work)

Question 5

∆E = 0

(show why)

Answer 5

EK + EG = E = constant

∆E_K + ∆E_G = ∆E = 0

∆E_K + ∆E_G = 0

∆E_K = - ∆E_G

∆E = 0

Question 6

E_G

Answer 6

E_G = mgh

Question 7

E_K

Answer 7

E_K =

Question 8

If E_g is constant

(non-isolated)

Answer 8

∆E_K = W

( ∆E_K + ∆E_g = W )

Question 9

If E_K is constant

(non-isolated)

Answer 9

∆E_g = W

( ∆E_K + ∆E_g = W )

Question 10

J / s = ?

Answer 10

1 J / 1 s = 1 W

1 watt

Question 11

efficiency equation

Answer 11

efficiency = ( E_out / E_in ) • 100%

Question 12

power equation

Answer 12

P = ∆E / ∆t

(P = J / s) = W (att)

Question 13

what makes up J

Answer 13

N • m

m² / s²

Question 14

non-isolated system total ‘work’ equation

Answer 14

W = F • d • cosø

Question 15

non-isolated ∆E equations

Answer 15

∆E = W

∆E =

∆E = E₂ - E₁

Question 16

One Watt

Answer 16

is the power of an energy transformation that converts 1 Joule of energy into another form in one second

Question 17

Specific heat capacity def.

Answer 17

the amount of heat absorbed that is required for 1kg of a substance to increase its temperature by 1 ˚C

(J / kg • ˚C)

Question 18

1 Watt

Answer 18

the power of energy transformation that converts 1J of energy into another form, in one second.

Question 19

1 Joule

Answer 19

the work done by 1N of force that produces a displacement of 1m

Question 20

1 Kelvin

(T_K)

Answer 20

T_K = T_C + 273.15