PHY 171 - Midterm Flashcards
What are the SI units for density? What is the formula?
rho = m/v
SI unit = kg/m^3
What is 1 g/cm^3 in 1000 kg/m^3?
1000 kg/m^3
What is 1 m^3 in L?
1000 L
What formula and SI unit for pressure?
P = F/A
SI unit = 1 N/m^2
What is the nature of pressure in fluids?
pressure is everywhere, pushes all ways equally
How does pressure change with depth in a liquid?
pressure increases with depth
In a liquid, does pressure vary across a horizontal line?
no
What is the equation for guage pressure?
pg = p - 1 atm
What is the solving strategy for a connected liquid?
set them equal to eachother
What is Archimedes’ Principle?
a fluid produces an upward buoyant force
What is equal to the magnitude of the buoyant force?
weight of the fluid displaced or desnity of fluid * volume submerged * grav constant
What determines if an object floats are sinks?
how the buoyant force compares to its weight (depends on density)
What is the equation of continuity for fluid dynamics and what does it indicate?
v1A1 = v2A2
- flow is faster in a narrower tube
- flow is slower in a wider tube
T/F: The flow rate of a dynamic fluid is constant.
True, Q = vA
What is Bernoulli’s equation mean in terms of energy?
it is the conservation of energy for fluids
How do wider sections of a tube with a dynamic fluid affect the pressure?
Pressure increases in wider spaces and decreases in narrower spaces
In a monometer, if the right side fluid is higher than the left, is rhogh positive or negative?
positive
What is oscillatory motion?
repetitive motion back and forth around an equilibrium position
What is simple harmonic motion?
sinusoidal oscillations (ex. mass on a spring)
What does the slope of a F vs position graph give?
the restoring force of a spring
What is a phase?
an angle of circular motion whose shadow matches oscillator and increases with time
If the value for the phase constant is between 0 and pi, is it positive or negative?
negative
if the value of the phase constant is between pi and 2pi, is it positive or negative?
positive
Where does an oscillating object have purely PE and purely KE?
purely PE at x = +/- A
purely KE at x = 0 (equilibrium)
Do period and frequency depend on amplitude for simple harmonic motion?
no
What is the equation for the restoring force of a pendulum?
F = -mgsin(theta)
What do the frequency and period of a pendulum depend on and not depend on?
depend on length of pendulum
does not depend on mass
What quantity must a physical (torsional) pendulum incorporate?
moment of inertia (I)
What are damped oscillations?
oscillations that slow down and stops due to external force
How does the envelope of damped oscillations decay?
exponentially
REMINDER:
fill in damped, lightly, heavily here!!
What is a driven oscillatin?
oscillator subjected to periodic external force
What is resonance?
large-amplitude response to driving force due to driving force frequency matching that of system (fext = fo)
What does a lightly damped peak with resonance look like on a resonance curve?
tall and skinny
What is a traveling wave?
organized disturbance traveling with well defined speed
What is a transverse wave?
wave in which displacement is perpendicular to direction of travel (ex. electromagnetic)
What is a longitudinal wave?
displacement is parallel to direction of travel
Do mechanical waves require a medium?
yes
How is wave speed increased ?
increasing tension or decreasing string density
What does a snapshot graph show and what are its axes?
x = position y = displacement
shows wave pulse (actual picture)
What does a history graph show and what are its axes?
x = time y = displacement
shows history of a particular point in medium (leading edge is closes to y-axis)
