Physics - September 2007

If a television or stereo is backed onto a window, will the sound of these devices travel more than if backed onto a solid wall?

2007-09-24 11:32:56 · 3 answers · asked by camelot 1

The 75.8 kg pilot does not want his radial acceleration to exceed 10.3 grams.

a) What is the minimum radies of the circular path?

b) At this radius, what is the net centripetal force exerted on the pilot by the seat belts, the fricion between him and the seat, and so forth?

2007-09-24 11:29:56 · 1 answers · asked by alex v 1

If you were on a 31.2deg. slope and an avalanche started 409m up the slope, how much time would you have to get out of the way? Answer in sec.

Acceleration of gravity is 9.8 m/s^2

2007-09-24 11:18:16 · 1 answers · asked by alex v 1

A ball is thrown straight upward and returns to the thrower's hand after 2.88 s in the air. A second ball is thrown at an angle of 34.0 degrees with the horizontal. The acceleration of gravity is 9.81 m/s2 .

At what speed must the second ball be thrown so that it reaches the same height as the one thrown vertically? Answer in units of m/s.

2007-09-24 11:13:26 · 1 answers · asked by fatiimaq08 3

will it move?

2007-09-24 10:53:22 · 1 answers · asked by sexysaraxx 4

2007-09-24 10:52:47 · 3 answers · asked by Anonymous

A dockworker applies a constant horizontal force of 75.0 N to a block of ice on a smooth horizontal floor. The frictional force is negligible. The block starts from rest and moves 16.0 m in 6.00 s
.
(a) What is the mass of the block of ice?


(b) If the worker stops pushing after 6.00 s, how far does the block move in the next 6.00 s?

2007-09-24 10:34:42 · 1 answers · asked by DJ 1

A gas is compressed from 600 cm^3 to 200 cm^3 at a constant pressure of 400 kPa. At the same time, 100 J of heat energy is transferred out of the gas.

2007-09-24 10:23:49 · 1 answers · asked by ryoukai_chang 1

A biologist found unique egg of dinosaur, and decided to hatch it. But when he was riding with precious egg in elevator, the cable was torn and elevator fell from height h=20m.

The scientist realized jumping will not help him, but being a true scientist, he decided to save at least the egg. Can he do so by throwing the egg upward?

2007-09-24 10:16:34 · 8 answers · asked by Alexander 6

what is momentum of a fly if it's traveling 1 m/s and has mass of 0.0001 kg?

2007-09-24 09:59:59 · 3 answers · asked by goofy 2

an antique carousel that's powerd by a large electric motor undergoes constant angular acceleration from rest to full rotational speed in 5 sec. when the ride ends, a brake causes it to decelerate steadily from full rotational speed to rest in 10 secs. compare the torque that starts the carousel to the torque that stops it.

2007-09-24 09:57:28 · 5 answers · asked by goofy 2

2007-09-24 09:51:33 · 5 answers · asked by Jooky15 2

2007-09-24 09:47:06 · 4 answers · asked by Anonymous

I'm having trouble with capacitance. Any input would be appreciated. Here is the Question:

You are to connect capacitances C1 and C2, with C1>C2, to a battery, first individually, then in series, and then in parallel.

Rank those arrangements according to the amount of charge stored, greatest first.

2007-09-24 09:36:02 · 3 answers · asked by i wonaaa 2

Physically what is it? Do we know? It is called a force, what use is that? What's it made of? If planets have it, how come they can make it? Do you need certain things or conditions to make gravity?

2007-09-24 09:22:41 · 11 answers · asked by Anonymous

a jetliner can fly 6.5 hours on a full load of fuel. Without any wind, it flies at a speed of 2.10 x 10^2 m/s. the plane is to make a round-trip by heading due west for a certain distance, turning around, and then heading due east for the return trip. during the whole flight, the plane encounter 55.0 m/s wind from the jet stream, which blows from west to east. what is the maximum distance that the plane can travel due west and just be able to return home?





A swimmer, capable of swimming at a speed of 1.3 m/s in still water (the swimmer can swim with a speed of 1.3 m/s relative to the water) starts to swim directly across a 2.2 km wide river. However the current is 0.91 m/s and it carries the swimmer downstream


a) how long does it take the swimmer to cross the river?


b) how far downstream will the swimmer be upon reaching the other

2007-09-24 09:12:57 · 1 answers · asked by Anonymous

Four point charges have the same magnitude of 3.3 x 10^-12 C and are fixed to the corners of a square that is 7.2 cm on a side. Three of the charges are positive and one is negative. Determine the magnitude of the net electric field that exists at the center of the square.

2007-09-24 08:33:14 · 1 answers · asked by Anonymous

a) light of a wavelength 400nm shines on the cathode. Will photoelectrons be emitted?

2007-09-24 08:28:16 · 1 answers · asked by nothingspecial 1

Henrietta is going off to her physics class, jugging down the sidewalk at a speed of 2.95 m/s. Her husbane Bruce suddenly realized that she left in such a hurry that she forgot her lunch of bagels, so he runs to the window of their apt, which is a ht of 45.1 m above the st level and directly above the sidewalk, to throw them to her. Bruce throws them horizontally at a time 4 a after Henrietta has passed below the window, and she catches them on the run. Ignore air resistance.

2007-09-24 08:28:12 · 1 answers · asked by dymestatus 1

What must her mim speed be just as she leaves the top of the cliff so that she will miss a 1.75 m wide and 9 m ledge below the top of the cliff ?

2007-09-24 08:21:27 · 1 answers · asked by dymestatus 1

The speed of a person standing at the equator relative to a person standing at the North Pole is
(a) 0 m/s (b) 385 m/s (c) 464 m/s (d) 928 m/s (e) 1253 m/s
(Note that 1 m/s = 2.2 miles per hour)

2007-09-24 08:20:43 · 2 answers · asked by DIIV 3

Pure substances are either "blank" or "blank"?

The substances in a "BLANK" mixture are evenly distributed throughout the mixture?

A material used for electrical wiring would need to have good?

2007-09-24 08:16:52 · 1 answers · asked by Anonymous

Physics Yuck!

2007-09-24 07:26:00 · 3 answers · asked by Mayhew 2

9.79m/s^2. Determine the acceleration of the rock in m/s^2

2007-09-24 07:08:01 · 1 answers · asked by s4_orce 1

the question says:
Compare the momentum of a 50-kg-dolphin swimming at 10.4 m/s and a 6,300-kg-elephant walking 0.11 m/s.

so what do i do? what kinda answer are they looking for? im just so confused physics is so not my forte!

2007-09-24 07:01:26 · 2 answers · asked by Anonymous

For the universal set U - {0,1,2,3,4,5,6,7} and the sets A= {1,5}, B = {1,2,3,4} and C={4,6}, list the elements in the following sets.

a. A "union" <-- ( should be an upside down U shape) B
b. A U B'
c. A (upside down U) (B U C)

2007-09-24 06:57:06 · 1 answers · asked by PhysicsDummy 2

The drawing shows three particles far away from any other objects and located on a straight line. The masses of these particles are mA = 363 kg, mB = 517 kg, and mC = 154 kg. Find the magnitude and direction of the net gravitational force acting on each of the three particles (let the direction to the right be positive).

http://i240.photobucket.com/albums/ff278/mysterypenguin12/111-1.gif

2007-09-24 06:39:03 · 1 answers · asked by mysterypenguin12 1

2007-09-24 06:29:02 · 4 answers · asked by Beme 2

The Power Because of a Poor transformer can be 80 Volts
When we run the fridge for example or water Pump it all runs on Lower Voltage (Its Not Good) but is it costing us MORE or Less to operate these things or is it the same ? What is the relationship between Voltage and Kilowatt hours?

2007-09-24 06:21:44 · 6 answers · asked by jojomontreal2000 2

the temperature will rapidly go down to almost absolute zero.

Then, how would the surface of Earth look like?

2007-09-24 06:10:31 · 2 answers · asked by Alexander 6