# Search results

1. ### Conservation Of Energy Problem

So this is the quaiton that i have problem w/: A 4kg bundle starts up a 30 degree incline with 128J of kinetic energy. How far willl it slide up the incline if the coefficient of kinetic friction between bundle and incline is 0.3? Because E_initial + Work = E_final and the Work done in the...
2. ### An gas molecule problem

I am stuck in this gas problem: You are given a 10.00 gram solid mixture of Ca(ClO_3)_2 and Ca(ClO)_2. When this mixture is heated, both componds decomplse, releasing oxygen gas and leaving behind solid CaCl_2 When this 10.00gram mixture is sealed in a 10.0-Liter evacuated vessel and heated...
3. ### Finding the resulant from the product

I am new to Chem, and I don't quite understand how to solve this problem: Component of citrus fruits is the bitter compound limonin, which contains only carbon, hydrogen, and oxygen. When a 1.000-gram sample of limonin is subjected to complete combustion, 2.432 grams of CO_2 and 0.574 grams...
4. ### Wave nature of light problem

Given a wavelength length \alpha, what is the maximum Width (D) of a single slit, which would have no diffraction minima? It seems like a proof problem to me and I am trying to get a head start. should I use D * sin (\theta) = m \alpha ?
5. ### Water wave

This question is related to the wave nature of light from Giancoli: Water waves having parallel crests 2.5cm apart pass through two openings 5cm apart in a board. At a point 2.0m beyond the board, at what angle relative to the "straight-through" direction would there be little or no wave...
6. ### Magnetic Force

Ok, this problem shows up on my test today and I was wondering how you can solve it: A circular coil of wire has a diameter of 20 cm and contains 10 loops, internal resistance of 8 ohms, and the coil is placed in a 2.00T external magnetic field. When 1 volt is applied to the coil, determine...
7. ### Thin len problem

This is a true of false question from my homework: Three light rays start out from a candle flame at the same time. To the right of the candle there is a lens, and to the right of the lens there is a screen. Ray A goes through the edge of the lens. Ray B goes through the center of the lens...
8. ### Converging lens

A bright object is placed on one sid eof a converging lens of focal length f, and a white screen for viewing the image is on the opposite side. The distance d_T = d_i + d_0 between the object and the screen is kept fixed, but the lens can be moved. Show that if d_t > 4f , there will be two...
9. ### More Geometric optics

Two lenses, one converging with focal length 20cm and one diverging with focal length -10cm, are placed 25cm apart. An object is placed 60cm in front of the converging lens. Determine (a) the position and (b) the magnification of the final image formed. I have a problem with this becasue...
10. ### Another geomatric optics

Each student in a physics lab is assigned to find the location where a bright object may be placed in order that a concave mirror with raidius of curvature r = 40cm will produce an image three times the size of the object. Two students complete the assignment at different times using identical...
11. ### Geometric Optics

Hey guys! I need some helps on an optics problem. It is from Giancoli Chapter 23, question 41: Question: A beam of light enters the end of an optic fiber (attachment B). Show that we can guarantee total internal reflection at the side surface of the material (at point a), if the index of...
12. ### EM wave energy and magnitude

Suppose a 50-kW radio station emits EM waves uniformly in all directions (a) How much energy per second crosses a 1.0m^2 area 100m from the transmitting antenna? (b) What is the rms magnitude of the E field at this point, assuming the station is operating at full power? (c) What is the voltage...
13. ### Peak value or rms?

I am always confused with rms value and peak value, so here is the problem: What will be the peak value of the current of a well-insulated 0.03\mu F capacitor connected to a 2.0-kV(rms) 720-Hz line? So first I find the reactance of the capacitor, which is: X_c=\frac{1}{2\pi fC} 7.4k...
14. ### Magnetism again

A horizontal rod is moved northward at a constant velocity throough a magnetic field that points straight down. Which statement is true? a) The West end of the rod is at higher potential than the east end. b) The East end of the rod is at higher potential than the West end. c) The top...
15. ### Magnetic field coil of wire problem

This is the problem taken from Giancoli Chapter 20, number 80: The magnetic field B at the center of a circular coil of wire carrying a current I is : B = \frac{\mu_{0}NI}{2r} , where N is the number of loops in the coil and r is its radius. Suppose that an electromagnet uses a coil 1.2m in...
16. ### Magnetic Field and Work

This is a true or false question relating magnetic field and work: A current-carryign wire placed in a magnetic field will gain kentic energy as the wire accelerates in response to the magnetic force. However, in applying the definition of work, ( W = F * D * cos x ), we realize that the...
17. ### Question regarding to magnetic field

You want to get an idea of the magnitude of magnetic fields produced by overhead power lines, You estimate that the two wires are each about 30m above the ground and are about 3m apart. The local power company tells you that the lines operate at 10kV and provide a maximum of 40MW to the local...
18. ### Question regarding to magnetic field

You want to get an idea of the magnitude of magnetic fields produced by overhead power lines, You estimate that the two wires are each about 30m above the ground and are about 3m apart. The local power company tells you that the lines operate at 10kV and provide a maximum of 40MW to the local...
19. ### Electric Current

A power station delivers 620kW of power at 12,000 V to a factory through wires with total resistance 3.0 ohms. How much less power is wasted if the electricity is delivered at 50,000V rather than 12,000V? I cannot quite picture what is going on in this problem. Is this a series circuit...

A 7.7 uF capacitor is charged by a 125-V battery and then is disconnected from the battery. When this Capacitor C_1 is then connected to a second (initially uncharged) capacitor, C_2, is the final voltage on each capacitor is 15V. What is the value of C_2 (The hint from the book is that...
21. ### Proton Kinetic Energy problem

An electron starting from rest acquires 6.3keV of KE in moving from point A to point B. How much KE would a proton acquire, starting from rest at B and moving to point A? The answer is 6.3keV. I don't understand why they have the same kinetic energy. Is it becasue proton has more mass and...
22. ### Question about electrial potential

The work done by an external force to move a -8.50{\mu}C charge from a point a to point b is 15.0*10^{-4}J. If the charge was started from rest and had 4.82 * 10^{-4}J of kinetic energy when it reached point b, what must be the potential difference between a and b. I am not sure if this is...
23. ### Electric Field inside a conductor

How come the electric field inside a conductor is equal to 0? How do you explain with Gauss's Law?
24. ### Simplify: (x+a)^2 * (x-a) ^2

Which is the fastest way to simplify: (x+a)^2*(x-a)^2 to (x^2-a^2)^2 ? thx
25. ### Basic electrostatic Force question

Sphere A carries a net charge and sphere B is neutral. Both are conducting spheres and they are placed near each other on an insulated table. Which statement best describes the electrostatic force between them? a) there is no force b/w them since one is neutral b) there is a force of...
26. ### Neutral object and electric field

Does a netural object experience a net force in an electric field? I dont quite understand the question. Can somebody draw a picture based on the description?
27. ### Gravitational force and electrical force

Suppose that electrical attraction, rather than gravity, were responsible for holding the MOon in orbit around the Earth. If equal and opposite charges Q were placed on the Earth and the Moon, what should be the value of Q to maintain the present orbit? Given these data: Moon = 7.35 \ast...
28. ### Earth's charge

How come the Earth is negatively charged?
29. ### A problem about Coulomb's Law

two charges, -Q and -3Q are a distance r apart. These two charges are free to move but do not because there is a third charge nearby. What must be the charge and placement of the third charge for the first 2 to be equilbrium? The answer is: The charge is 0.4Q and the distance is 0.37l...