The G string on a violin is 30 cm long. when played without fingering, it vibrates at frequency 196 Hz. The next higher notes on the scale are A(220 Hz), B(247 Hz), C(262 Hz), and D(294 Hz). How far from the end of the string must a finger be placed to play these notes?
In: Physics
How does driving force factor into dendritic integration? And so then why is integration sublinear?
What is dendritic attenuation? Why does it occur? Why does it matter?
What is "shunting inhibition"? What properties could this provide neurons with for processing information?
In the context of the simulations from NIA, what is meant by “deliberation time” for an AP?
Describe the oscillations in mechanoreceptors simulation in detail based on the plots of voltage, current, and conductance.
Is action potential size fixed over a range of inputs? Present evidence one way or the other from the third simulation in NIA.
In: Physics
In: Physics
A 0.480-kgkg hockey puck, moving east with a speed of 3.05 m/sm/s , has a head-on collision with a 0.800-kgkg puck initially at rest.
Assuming a perfectly elastic collision, what will be the speed (magnitude of the velocity) of each object after the collision?
In: Physics
A model of a red blood cell portrays the cell as a spherical capacitor, a positively charged liquid sphere of surface area A separated from the surrounding negatively charged fluid by a membrane of thickness t. Tiny electrodes introduced into the interior of the cell show a potential difference of 100 mV across the membrane. The membrane's thickness is estimated to be 103 nm and has a dielectric constant of 5.00.
(a) If an average red blood cell has a mass of 1.10 ✕ 10−12 kg, estimate the volume of the cell and thus find its surface area. The density of blood is 1,100 kg/m3. (Assume the volume of blood due to components other than red blood cells is negligible.)
| volume | m3 |
| surface area | m2 |
(b) Estimate the capacitance of the cell by assuming the membrane
surfaces act as parallel plates.
F
(c) Calculate the charge on the surface of the membrane.
C
How many electronic charges does the surface charge represent?
In: Physics
Electrostatic Force and Equilibrium
Consider a rhombus with side of length L. The rhombus has two
pair
of equal interior angles. Label one of these pair θ and the other
φ. Four
identical, positive point charges, q are placed on the vertices of
the rhombus.
Draw the configuration.
a) Obtain a symbolic expression for the electric field at one of
the vertices
(your choice) and then at an adjacent vertex (Do you now know the
electric
field at all of the vertices? Why/why not?). Does it matter that
there is a
charge at the vertex? Comment on the direction of the electric
field at your
two vertices. Does this make sense? Why?
b) We now allow the angles to vary, subject to the constraint
that the figure
must remain a rhombus. Label one of the vertices P. What θ value
and φ
value, (in degrees), minimizes the electric field at P . Hint: You
should only
have to do one minimization, as there is a constraint between θ and
φ.
c) Plot the magnitude of the electric field at P as a function
of the angle
opposite P ( This will be θ or φ depending on how you labeled your
figure).
Please show your work and explanation. Thanks for your help.
In: Physics
A metal block of mass 1.830 kg is hanging from a string. The tension in the string is 1.089×101 N. The block is submerged in a beaker of fluid and is stationary. What is the magnitude and direction of the buoyant force acting on the block?
In: Physics
An electric field given by Upper E Overscript right-arrow EndScripts = 3.2i Overscript ̂ EndScripts - 9.5(y2 + 6.2)j Overscript ̂ EndScripts pierces the Gaussian cube of edge length 0.890 m and positioned as shown in the figure. (The magnitude E is in newtons per coulomb and the position x is in meters.) What is the electric flux through the (a) top face, (b) bottom face, (c) left face, and (d) back face? (e) What is the net electric flux through the cube?
In: Physics
In: Physics
Please answer the following questions with a moderate amount of detail:
1. In 1921, Albert Einstein received a Nobel prize for his interpretation of an experiment that could not be explained using Maxwell
In: Physics
A 480 kg horse pulls a 260 kg cart with a constant acceleration of 0.800 m/s2. Assume the only force acting on the horse comes from the cart pulling on it.
(a)What force does the horse extert on the cart?
______ N
(b)What force does the cart exert on the horse?
_______N
(c)What is the net force acting on the horse?
______N
In: Physics
a) In a proton at one certain moment, the down quark has a strong color charge of red. What are the color charges of the two up quarks? (Type each color in lowercase with a space between each one.)
(d) In a pi meson at a certain time one quark has a red color.
What is the color of the antiquark at that time?
In: Physics
A home run is hit in such a way that the baseball just clears a wall 14.0 m high, located 128 m from home plate. The ball is hit at an angle of 33.0
In: Physics
A person with mass mp=80 kg is standing at rest on a horizontal, frictionless surface holding a ball of wet clay with mass mg=10 kg . In front of the person is a large block with mass M=20 kg at rest next to a spring with stiffness k=100 N/m . The person throws the ball horizontally, it sticks to the block, and then ball and block slide and compress the spring a distance 1=0.75 m away from equilibrium before the ball-block springs back toward the person. (Assume the distance the ball is thrown is short, so that we can ignore the vertical component of its velocity.)
a) Find v P1 (the speed of the person after the ball was thrown)
b) Find Vs (the speed at which the person, ball, and block move after the ball and block bounced back off the spring and collided with the person)
c) If it takes 0.2 seconds for the person and the ball-block to get to the same velocity, find the impulse on the person due to the ball-block. AND find the force on the person due to the ball-block,
(Please be careful in your answer in part b because the person is also moving after he throws the ball. So, this will effect the final answer for their overall speed. And, please don't copy from others. They are all wrong. Thanks.
In: Physics
1.A circuit of resistors connected in series is plugged in a 120 V outlet. What can you tell about the voltage on each of resistor and current in each resistor?
2.A circuit of capacitors connected in parallel is plugged in a 120 V outlet. What can you tell about the voltage on each capacitor and current in each capacitor?
In: Physics