hello I would like some help with the first part of this homework.
for the moment i have done this:
E initial=m*g*h
Efinal= 1/2 m*v ^ 2+1/2I*ω ^ 2
Ei=m*g*h+1/2I*ω ^ 2
Ef=1/2*m*v ^ 2
my doubt is with the potential energy since it confuses me when there is or not
Homework Statement
Gold, which has a density of 19.32 g/cm3, is the most ductile metal and can be pressed into a thin leaf or drawn out into a long fiber. (a) If a sample of gold with a mass of 3.872 g, is pressed into a leaf of 5.372 μm thickness, what is the area of the leaf? (b) If...
Homework Statement
In your research lab, a very thin, flat piece of glass with refractive index 2.00 and uniform thickness covers the opening of a chamber that holds a gas sample. The refractive indexes of the gases on either side of the glass are very close to unity. To determine the thickness...
Homework Statement
Hello All,
Please help me to find the force required to rotate a body of 4 Kg mass from 0° to 90° in 5 second. this force is acting at center of gravity. (Image: case 1)
CASE-2: Force acting away from center of gravity. (Image: case 2)
Homework Equations
The Attempt at...
Homework Statement
An elevator takes a 70 kg person from street level to the top of a 400 m sky-scraper in 4 minutes. The mass of the elevator is 500 kg.
a] At what rate is the elevator plus the person gaining potential energy?
b] What power is the elevator plus the person experiencing as...
Homework Statement
A light ray shines from a diamond (n = 2.42) into water (n = 1.33), and no refraction occurs. What is the angle of incidence?
0°
30°
45°
60°
Homework Equations
sin θc = nr/ni ?
The Attempt at a Solution
I thought that by finding the critical angle then anything...
Homework Statement
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Homework Equations
N = PV/ kbT
The Attempt at a Solution
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Homework Statement
1. Homework Statement [/B]
The displacement y of standing wave that is obtained by a superposition of waves :
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Y2 = 3 sin (2##\pi##(0.5t + 0 25 x))
Homework Equations
Formula for standing waves
Y = 2Asinkx coswt
The Attempt at a Solution...
Homework Statement
[/B]
There is lead XY shaped as straight wire. Next to it, circular lead with radius 0.10 m.
They are in the same plane.
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Curent flowing through XY is 15.7 A
Homework Equations
The Attempt at a Solution
1) find magnetic field (B) at...
Homework Statement
A capacitor with initial charge q0 is discharged through a resistor. What multiple of the time constant τ gives the time the capacitor takes to lose
(a) the first 1/8-th of its charge
(b) 7/8-th of its charge?
Homework Equations
The Attempt at a Solution
since ı know...
Homework Statement
(Is the image read-able now? )
The fig 1 shows the relationship between voltage and current when voltage is applied to a certain light bulb.
Next, in fig 2, the bulb is connected in series with a 12-V battery and a 5 ohm resistor.
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1. The problem statement, all variables, and given/known data
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Homework Statement
[/B]
A circular ring of radius "a" has a total charge Q uniformly distributed along the top half. (Q is distributed along the semicircle in quadrants I and II). What is the potential at a point located on the bottom of the ring (observation point is on the ring in quadrant...
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A football punter can punt a maximum range of 40.8 m. If he instead wants to punt only 34.6 m, but maximize the time the ball is in the air, at what angle from the horizontal should he kick the ball, and how long will it stay in the air if he hits it perfectly? (neglect air...
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An m = 1.3 kg block and an M = 3.0 kg block have a spring compressed between them and rest on a frictionless table. With a stopper in place that prevents m from moving, the spring is compressed and released so that M moves away with a speed 2.0 m/s.
The spring is...
Homework Statement
A block of mass m =0.75 kg is set on a large cart of mass M = 6.5 kg. The cart's rollers are frictionless, but there is a coefficient of kinetic friction of 0.36 between the cart's surface and the block. The cart is at rest when the block is given an initial speed of 5.2...
Homework Statement
Assume a Gaussian laser beam ( 1064 nm wavelength) having an FWHM-diameter(intensity) of 5 mm. By transmission through a thin nonlinear crystal, a new wave is generated that is proportional to the square of the incoming field (and therefore radiates at twice the frequency, or...
A spring of spring constant k sits on a frictionless horizontal table, one end of the spring is attached to a wall the other end to a block of mass M= 2kg, also resting on the frictionless table. Another block of mass m=450g moving at a speed of 7m/s collides in-elastically with the block of...
Homework Statement
I have an image with the question here: http://imgur.com/TGG9VTx.jpg
The red text is the answer. I havent been able to get it without contradicting what Ive been told.
Homework Equations
I know m1x1 + m2x / m1+m2 is centre of mass in 2d plane, but I dont know how that...
Homework Statement
physics major practical, I was supposed to change the mass and find how it effects the safety of the jumper.But since hooks law doesn't follow bungee cord i really cant find a relationship.
Homework Equations
The Attempt at a Solution
I used a bungee cord and hung...
Homework Statement
Hello! I have a physics homework question I just need help at!
What I am supposed to do is calculate the value for free-fall acceleration, ag, for each of my trials that I did in my lab. I supposed to use the equation for the period of the simple pendulum, T=2π√l/g, but I...
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[PLAIN]http://[url=http://postimg.org/image/oif09fcd5/]
3. This is my atempt
[PLAIN]http://[url=http://postimg.org/image/4qavbtv4p/]
Homework Statement
You've probably noticed that TV screens and computer monitors have an annoying tendency to accumulate dust. Wanting to understand this better, you decide to model the situation as follows: you assume a small mote of dust might have an excess charge of 1 nC and a mass of 5...
Homework Statement
Earth actually has an electric field of 1.0 x 10^2 N/C at its surface pointing toward the center.
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i) direction
ii) shape
iii) how it changes as height increases.
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