chapter 3

Question 1

equation for kinetic energy and definiton

Answer 1

KE = 1/2mv²

objects in motion have kinetic energy

Question 2

kinetic energy is proportional to?

kinetic energy increases exponentially with?

Answer 2

mass

velocity

Question 3

kinetic energy has units of?

Answer 3

Joules (same as work so work can also = 1/2mv²

Question 4

what is the equation and definition for potential energy?

Answer 4

refers to the energy of an object has stroed within itself

PE_grav= mgh

Question 5

what are the types of potential energy?

Answer 5

• gravitational
• elastic
• electric
• magnetic

Question 6

Potential energy is proportional to?

Answer 6

mass

Question 7

what is the equation for elastic potential energy and what is its defintion?

Answer 7

PE_elastic= 1/2kx²

Question 8

what is the principle of conservation of energy?

Answer 8

• a fundamental law of nature
  
  • states that energy can neither be created nor destroyed, just transferred from one form to another

Question 9

what is the equation for conservation of energy?

Answer 9

E_initial = E_final

• if we neglect non-conservative forces, the new equation states that the sum of the kinetic and potential energies remains the same
  
  • KE_initial + PE_initial = KE_final + PE_final
    
    • _​if talking in the context of gravitation, equation is
      
      • 1/2mv_i² + mgh_i = 1/2mv_F² + mgh_f

Question 10

context of ideal springs equation neglecting non-conservative forces

Answer 10

1/2mv_i² + 1/2kx_i² = 1/2mvf² + 1/2kxf²

Question 11

the principle of conservative energy still holds true when what forces are at play?

Answer 11

non-conservative forces

equation: E_initial - E_conservative = E_final

• recognize that some energy gets dissipated often in the form of friction/thermal energy
  
  • solve same way as conservative and realize some energy is dissipated to account for a small change

Question 12

what is the force energy theorom and its equation?

Answer 12

this theorem states that the work performedon or by an object is equal to the change of its kinetic energy

the work we cna obtain using this theorem can be either positive or negative

W = deltaKE = KE_final - KEinitial

Question 13

the convention when referring to energy is for a positive change in energy to reflect energy?

Answer 13

put into a system

Question 14

the convention when referring to energy is for a negative change in energy to reflect energy?

Answer 14

energy taken out of a system

Question 15

what is the equation to meausre energy transfer?

Answer 15

W = KE_final = KE_intial and substitute in the measure v_i and v_f calues into the formula:

E_transferred = 1/2mv_f² - 1/2mv_i²

Question 16

pressure and volume are related to?

Answer 16

work

Question 17

P = F/A is equal to?

Answer 17

F = PA

Question 18

when we combine W = F delta(x) we get?

Answer 18

W = PA delta(x)

Question 19

W = PA delta(x) also equals?

Answer 19

W = P delta(V)

Question 20

energy can also be described in what units?

Answer 20

L•atm with 1 atm = 101J

Question 21

Graph of W= P (delta v)

Answer 21

volume is on the x-axis (independent variable

pressure is on the y-axis (dependent variable)

area under the curve = work

Question 22

when gas expands?

Answer 22

volume must increase, and work done is negative

Question 23

when the gas is compressed?

Answer 23

volume must decrease and the work done is positive

Question 24

as pressure increases?

Answer 24

volume decreases

Question 25

as pressure decreases?

Answer 25

volume increases