Physics - March 2007

Hello guys, I really need help with this physics problem. It has been bugging me for a while and I keep getting stuck. If you can't solve it, if you know where I can find a site that has solutions this would be a great help. Thanks!

A l.0 kilogram object is moving horizontally with a velocity of 10 meters per second, as shown above, when it makes a glancing collision with the lower end of a bar that was hanging vertically at rest before the collision. For the system consisting of the object and bar, linear momentum is not conserved in this collision, but kinetic energy is conserved. The bar, which has a length l of 1.2 meters and a mass m of 3.0 kilograms, is pivoted about the upper end. Immediately after the collision the object moves with speed v at an angle  relative to its original direction. The bar swings freely, and after the collision reaches a maximum angle of 90° to the vertical. The moment of inertia of the bar about the pivot is Ibar = ml²/3 Ignore friction.

2007-03-27 04:37:04 · 1 answers · asked by Jess 1

If an object is going backwards in time, would it be perceivable to those going forward in time?

2007-03-27 04:22:38 · 7 answers · asked by Luis 6

...it would be to fly to California saying there both the same distance away from Maryland. And the plane is fly at 1000mph each trip.

2007-03-27 04:21:12 · 4 answers · asked by Anonymous

Metals, such as copper and silver, can become charged by induction, while plastic materials cannot.

2007-03-27 04:20:40 · 3 answers · asked by Anonymous

Say theoretically if I had a spaceship, and was close to the sun, but traveling backwards in time(if regular time is T, then I would go at -T), would the sun be cold?

2007-03-27 04:20:29 · 9 answers · asked by Luis 6

If I stopped time right now, and somehow moved an object within that stopped time, what would happen? I'm asking this from I suppose an atomic perspective, as I would be moving an object and atoms would not be able to move into the space it left, would this mean that there would be a void(lack of matter) where the object was?

Would I only be able to stretch objects in stop-time?

2007-03-27 04:17:13 · 12 answers · asked by Luis 6

2007-03-27 03:56:33 · 2 answers · asked by Chad B 1

(Assume that teh charges are located at a point.)
A ballon rubbed against denim gains a charge of -8.0 uC.

2007-03-27 03:45:38 · 2 answers · asked by Anonymous

A)find the magnitude of acceleration of the proton
B)how long does it take the proton to reach its speed
C)how far has it moved in that interval
D)What is the kinetic energy at the later time

2007-03-27 03:11:50 · 1 answers · asked by Kayla H 1

Between each pair of vertebrae of the spine is a disc of cartridge of thickness 0.5 cm. Assume each disc has a radius of 0.04 m. The shear modulus of cartridge is 107 N/m2. A shear force of 20 N is applied to one end of the disc while the other end is held fixed. What is the resulting shear strain?

2007-03-27 02:58:47 · 1 answers · asked by Anonymous

A force of 60 pN is required to stretch a sample of DNA of length 45 nm and Young's modulus 1.0x108 Nm2 by 15.0% of its original length. Determine the effective cross-sectional area of the DNA molecule in units of nm2.

2007-03-27 02:57:45 · 1 answers · asked by Anonymous

A human hair breaks under a tension force of 1.2 N. If the tensile strength of human hair is about 2.0x108 Pa, what is the diameter of the hair in microns (10-6m)?

2007-03-27 02:56:39 · 2 answers · asked by Anonymous

Resilin is a rubber-like protein that helps insects to fly more efficiently. The resilin, attached from the wing to the body, is relaxed when the wing is down and is extended when the wing is up. As the wing is brought up, some elastic energy is stored in the resilin. The wing is then brought down with little muscular energy, since the potential energy in the resilin is converted back into kinetic energy. Resilin has a Young's modulus of 1.7x106 N/m2. If the insect wing has resilin with a relaxed length of 2.0 cm and with a cross-sectional area of 1.0 mm2, find the magnitude of the force (in N) that the wing must exert to extend the resilin to 4.0 cm?

2007-03-27 02:55:01 · 1 answers · asked by Anonymous

Abductin is an elastic protein found in scallops, with a Young's modulus of Y=4.0x106 N/m2. It is used as an inner hinge ligament, with a cross-sectional area of A=0.78 mm2 and a relaxed length of L0=1.0 mm. When the muscles in the shell relax, the shell opens. This increases efficiency as the muscles do not need to exert any force to open the shell, only to close it. If the muscles must exert a force of 1.8 N to close the shell, by how much (in mm) is the abductin ligament compressed?

2007-03-27 02:52:43 · 1 answers · asked by Anonymous

2007-03-27 02:43:58 · 2 answers · asked by Anonymous

What I feel is wave nature of light can also account for photoelectric effect if we reconsider nature of light. light is considered both as particle and as wave but there is no mean of visualising both nature of light.What I believe is, light is a particle(charged) moving in a manner that its path forms a wave we already know that when a charged particle is stationery it only has electric field but when it is moving it has both electric and magnetic field while we know light has both electric as well as magnetic field therefore can't we consider light as chrged particles moving in wave form one question may arise that if light considered as particle(charged) moving in wave form than what is the restoring force maintain such wave,then it is the electric and magnetic forces acting on moving charged paricles which make particle of ligh vibrate as wave. If this proposed nature of light is accepted than it would account for optical as well as photoelectric phenomenon. please contact me.

2007-03-27 02:36:00 · 2 answers · asked by umesh the unconventional 2

If a television is positioned so that it is badly seen owing to light reflected from its surface, it can often be seen clearly through a polaroid filter. Why is this???

2007-03-27 02:21:26 · 4 answers · asked by acourting 1

difference between the protons initial and ending point is___. (proton charge=+1.6x10^-19 C)

2007-03-27 02:01:11 · 1 answers · asked by Kayla H 1

2007-03-27 01:53:17 · 1 answers · asked by ivan a 1

Wat will the sound b like when the following are forks r vibrating?
1- short fork with box underneath
2- short fork with no box
3- long fork with box
4- long fork with no box

2007-03-27 01:50:36 · 1 answers · asked by sαrαн♥mıss ©υяlz 3

2007-03-27 01:38:43 · 3 answers · asked by Anonymous

2007-03-27 01:37:26 · 1 answers · asked by Anonymous

2007-03-27 01:36:50 · 7 answers · asked by Anonymous

2007-03-27 01:36:09 · 6 answers · asked by bellevue r 1

2007-03-27 01:34:08 · 1 answers · asked by Anonymous

its passover and suc a method would be very usefull in the clean up neccesary

2007-03-27 01:34:01 · 2 answers · asked by harry s 1

We know that light is made up of particles called photons.At absolute zero temperature(-273 c or 0 k) kinetic energy of body becomes zero so will light also stop at that temperature being made up of photons.

2007-03-27 01:24:35 · 7 answers · asked by Anonymous

==========
Everyone knows, that absolute temperature T=0K
cannot be reached. But is it enough reason to think
that space T=0K doesn’t exist?
The birds communicate with songs.
If I cannot understand songs of birds does it mean
that they cannot exchange information with songs?
===============

2007-03-27 01:23:41 · 5 answers · asked by socratus 2

In Physics class, we've been doing electricity and magnetism. The part on charge polarization is extremely brief. It just says that in a conductor, free electrons move over the surface from one side to the opposite side. What happens when they move to another side?
Could anyone please explain to me charge polarization in both conductors and insulators, as well as when a charged object polarizes another, why is there an attraction?

2007-03-27 00:34:50 · 2 answers · asked by Orange Peel 2

a thick section of rubber was found to be undercured when vulcanised for 10 minutes at 150c. an attempt was made to overcome this problem, the vulcanisation temperature was reduced to 130c.

what is the new cure time at the lower temperature?

2007-03-27 00:31:24 · 4 answers · asked by Anonymous