PHYSICS 5B Lecture Notes - Lecture 1: Plasmid, Conservative Force, Energy
Review of Energy and Energy Transfer (Ch 10)
*form of energy .
-K =kinetic energy
I
m(k = Imv ')
-U= Potential Energy
↳Ug =gravitational
:
/(ug= mgh)
.
1/11/11
↳Us = elastic In
spring
energy
R1
mmmm Us ,I kx
:
:.
:
www.nmD
it xt
.
-Ein = Thermal energy
Ednem = chemical energy
-For a system:
Total energy
: E = Kt Ut Etn + Fchem
-Energy transfer from one kind to another within a system
Ksystem
ut
'
I
.
\ttn In this case :energy is Conserved
,
oE=o
.
EI : Drop a 1kg ball to the ground .
ugh
,,
,kETh ¥11.Fi=¥
£m/v2
=
mgh
✓ =
Tngh = 2.9k = 4.4 mls
*Energy transfer between a system and Its environment through work Orland heat
.
environment
system
*work = mechanical energy by pushing or pulling
→→ →F1
W.
-F. d→d1 o
,
E± : Pull a box by IN force at 450 for a distance of lm
,F
÷
' W = 1. 1cos G = I. 1 cos 45 = 0.7 J
IM
.
Work -Energy Theorem : OE = N
↳Ef -E;= W
II
-
oE= F.
d
h
t#so
.
