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=-1.8cm Some Formulas

Selected Math Formulas
Circumference of a circle: $C=2\pi R$
Area of a cricle: $A=\pi R^2$
Volume of a sphere: $V=\frac{4}{3}\pi R^3$
Surface area of sphere: $A=4\pi R^2$

International System of Units
Unit of is the
length meter (1 m)
time second (1 s)
mass kilogram (1 kg)

If prefix multiply by if prefix divide by
giga- (G) 1 billion centi- (c) 100
mega- (M) 1 million milli- (m) 1000
kilo- (k) 1000 micro- ($\mu$) 1million
    nano- (n) 1 billion

Motion
Speed: $v=\frac{d}{t}$; $[v]$=m/s
Velocity: $\vec v$ = speed and direction
Acceleration: $\vec a=\frac{\Delta\vec v}{t}$; $[a]$=m/s$^2$
Uniform acceleration: $a = $ constant:
$v=v_0 + at$
$d=v_0 t + \frac{1}{2} at^2$
Free fall:
vertical acceleration $a=g=9.8$ m/s$^2$
horizontal acceleration $a=0$

Forces
Newton's second law: $\vec F=m\vec a$; $[F]$=kg m/s$^2$=N (newton)
Newton's third law: action = reaction
Weight: force of gravity $w=mg$
Centripetal acceleration: $a_c=v^2/r$
Centripetal force: $F_c=ma_c$

\begin{displaymath}\mbox{\it Newton's law of universal gravitation: } F=G\frac{m_1m_2}{r^2}\end{displaymath}


Gravitational constant: $G=6.67\times 10^{-11}$ Nm$^2$/kg$^2$

Work and Energy
Work: $W=Fd$; $[W]$=Nm=J (joule)
Power: $P=W/t$; $[P]$=J/s=W (watt)
Kinetic energy: $KE=\frac{1}{2}mv^2$; $[KE]$=J
Gravitational potential energy: $PE=mgh$; $[PE]$=J
Conservation of energy: $ E = KE + PE = $constant.

Linear Momentum
Impuls and Momentum: $F\Delta t=\Delta p$, $p=mv$
Conservation of momentum: If $F_{external}=0$ then $p_{total}=$constant; $m_1\vec v_{1i}+m_2\vec v_{2i} = m_1\vec v_{1f}+m_2\vec v_{2f}$


width3.55in height0.6pt Instructor: Joerg Reinhold, Department of Physics, FIU CAPA©msu


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CAPA Account 2007-01-30