__ __

__Chapters from the textbook__*:*

$**Introduction, motion, force,
energy - Chapters 1 - 7**

$**Structure of matter -
Chapter 11**

$**Thermodynamics - Chapters 13
- 15**

$**Astrophysics and cosmology -
Chapters 32-33.**

__FORMULAS AND LAWS:__

__Motion:__

**x** - Displacement (distance)

**v** - Velocity

**a** - Acceleration

**t** - Time

__ __

__Newton's Laws__**:**

*Every body continues in its state of rest or of uniform speed in a straight
line unless it is compelled to change that state by forces acting on it.*

*The acceleration of a body is directly proportional to the net force acting on
it and inversely proportional to its mass. The direction of the acceleration is
in the direction of the applied force.*

*Whenever one object exerts a force on a second object, the second object
exerts an equal and opposite force on the first.*

**Weight** = mg

__Circular Motion__

**F -** Centripetal Force

__Law of Universal Gravitation__**:**

^{-11}
Nm^{2}/kg^{2}

__Energy:__

^{2
}Gravitational
Potential Energy = Weight x height = mgh

* **:** Thermodynamics*

*The change in internal energy of a closed system is equal
to the heat added to the system minus the work done by the system* -

**2nd. Law - Alternative difinitions:**

*-Heat flows spontaneously
from a hot object to a cold object***-**

*- No device is possible
whose sole effect is to transform a given amount of heat completely into work.-*

*- Natural processes tend to
proceed toward a state of greater disorder***-**

**Entropy - measure of disorder ****@**** Number of ways that energy
can partition.**

**Work ****»**** Heat ****»**** Energy---4180 Joule = 1 Cal
= 1 Kcal.**

**Temperature - Measure of internal energy.**

**Temperature
Scales: °F = 32 + (9/5)°C**

**°K = 273 + °C**

**Heating an
Object: Q = mc(T - T _{0})**

**(m - mass, c - specific
heat, T - final temperature, T _{0} - initial temperature)**

**Maximum Efficiency of Heat Engine = (Work output/
Heat input) = 1 - T _{c}/T_{H}**

**(T _{c} - Temperature
(Kelvin ) of cold reservoir, T_{H }- that of hot reservoir)**

**Ideal Gas
Law: PV = NkT**

**(P - pressure, V - volume, N
- No. of molecules, T - Absolute (Kelvin) Temperature, k - Boltzmann Constant =
1.38x10 ^{-23} Joule/°K) **

**Earth and Cosmological Energy Balance**

** ****Speed of light – c=3x10 ^{8}
m/sec. **

** **

**C = **8**/T **8 ** wavelength; T – period; c – speed of
light **

** **

**f = 1/T frequency ; c= f **8

** **

**1nm = 10 Angstroms = 10 ^{-3 }
micrometers = 10^{-9}m= 10^{-7}cm. **

** **

**The
Electromagnetic Spectrum**:

**Stefan
Boltzman Law:**

**For ideal blackbody the
total rate of emission is: **

**P _{e} = sAT^{4}**

** **

**T – temperature in ^{0}K;
A – area in m^{2}; s – Stefan Boltzman constant = 5.67x10^{-8}W/m^{2}.^{0}K
**

**P _{e} – total emitted power in watts**.

** **

**Wien
Law:**

8_{max}
**= 2.9x10 ^{-3}/T. **

** **8_{max} **in meters – wavelength of the maximum of the spectral distribution**.

** **

**Hubble’s
Law:**

** **

**V =
Hd**** **

** **

**V – velocity of galaxies
moving away from us; d – distance of the galaxies; **

**H – Hubble’s constant = 15km/sec per million
light year of distance**.

** **

**Issues to discuss:**

· **The greenhouse effect**

· **Earth’s energy balance**

· **The cosmological energy
balance – The microwaves background radiation as a probe of the beginning of
the universe.**