Physics - December 2006

5 (part 1 of 3)
A block is at rest on the incline.The coefficients of static and ki-
netic friction are ¹s = 0:49 and ¹k = 0:42, respectively.
The acceleration of gravity is 9:8 m/s2. The mass is 31 kg.
The angle of the incline is 23 degrees. What is the frictional force acting on the 31 kg mass? Answer in units of N.
(part 2 of 3)
What is the largest angle which the incline can have so that the mass does not slide down the incline? Answer in units of degrees.
(part 3 of 3)
What is the acceleration of the block down the incline if the angle of the incline is 33 ± ? Answer in units of m/s2.

2006-12-01 12:34:21 · 1 answers · asked by kavita 1

A U-tube of constant cross-sectional area, open to the atmosphere, is partially filled with a heavy liquid with density of 9.04 g/cm^3. A light liquid with density 2.01 g/cm^3 is then poured into both arms. If the difference in the height of the heavy liquid is 1.31 cm, determine the value of the difference in height of the light liquid hl (in units of cm).

2006-12-01 12:25:26 · 1 answers · asked by Mariska 2

An elevator has a loading capacity of 300% of its mass and weighs 0.5tonnes. When accelerating, the elevator gains its maximum speed of 2m/s in 1.5sec and decelerates with equal parameters. So:

a) What is the tension in each of the 3 ropes when moving the fully occupied elevator up and down?

b) The steel ropes have a dimeter of 2cm and run each over a wheel of 1m radius. What percentage compression and expansion does the wire experience when being moved over the wheel?

2006-12-01 11:53:46 · 3 answers · asked by susiebondi 1

When seven people whose average mass is 86 kg sit down in a car they find that the car drops 0.98 cm lower on its springs. Then they get out of the car and bounce it up and down. What is the frequency of the cars vibration if its mass (empty) is 3743 kg (in Hz). Acceleration of gravity is 98.8 m/s^2.

2006-12-01 11:46:06 · 1 answers · asked by Dee 4

Yes I would like an answer to thins question...
Why do you think doorknobs are located where they are on a door?
I believe it has to do with being more efficient because on the law of angular momentum. Any thoughts?

-asian_al

2006-12-01 11:41:50 · 6 answers · asked by Anonymous

(a) Find the energy absorbed in each cycle. in kJ
(b) Find the time required to complete each cycle. (s)

2006-12-01 11:40:06 · 1 answers · asked by melbourne 1

Is that related to the Zeeman effect?If light is composed of both fields then, any of the two fields would cause interaction,thus affecting light ether by bending or interference?Did ever Michelson adn Morley ever considered the earth magnetic field interaction with lightin their experiment?

2006-12-01 10:54:32 · 4 answers · asked by goring 6

One that's always puzzled me... three pins in a plug, the earth, the live and the neutral. The live is the fused one and even sounds like it's going to hurt you, but the neutral one doesn't have a fuse - does that mean you wouldn't get a shock if you touched the neutral wire? Here's the real puzzler - as mains is Alternating Current shouldn't the neutral be just as hazardous as the live?

2006-12-01 10:53:57 · 11 answers · asked by go_on_tell_us 1

A pair of bumper cars in an amusement park ride collide in a perfectly elastic collision as one approaches the other directly from the rear. One has a mass of m1 = 439 kg and the other m2 = 546 kg, owing to differences in passenger mass. The lighter one approaches at v1 = 4.36 m/s and the other is moving at v2 = 3.62 m/s.

What is the velocity of the lighter car after collision, the heavier car after collision, and the change in momentum of both the heavier and lighter car?

How would you determine the solution?

2006-12-01 10:31:18 · 2 answers · asked by gunder53534 2

A cylinderical shaped metal rod is used to conduct heat. When the temperature at one end is 100 degree Celsius and at the other end is 20 degree Celsius, heat is transferred at a rate of 16 J/s. The rod is then stretched uniformly to twice its original length. If again it has ends at 100 degree Celsius and 20 degree Celsius, at what rate will heat be transferred between it ends?

The answers that are given to me are:
4 J/s
8 J/s
32 J/s
2 J/s
64 J/s
16 J/s
1 J/s

2006-12-01 10:31:07 · 2 answers · asked by jay s 1

I need to know this before monday!please answer my question. say anything that will help me answer this question!!!!!!!!!!!!!!!!!!!!!!!!

2006-12-01 10:16:07 · 5 answers · asked by tesiebear 2

Please list you sources. Thank you.

2006-12-01 10:13:13 · 2 answers · asked by Izzy 2

of force constant 6 N/m that is free to oscillate on a horizontal, frictionless track. The mass is displaced 8 cm from the equilibrium point and released from rest.

A) Find the period of motion in units of s.
B) Find the maximum speed of the mass in m/s.
C) Find the maximum acceleration of the mass in m/s^2.

Note for the length on the horizontal track beyond the 8 cm x=0.

2006-12-01 09:44:02 · 1 answers · asked by Dee 4

Here's a diagram, BUT use 591 lb for the weight (NOT 500 lb):
http://www.webassign.net/sf/p9_24.gif

Piston 1 has a diameter of 0.25 in. and is attached to a lever arm a distance of 2 in from the pivot point. Piston 2 has a diameter of 1.4 in. An external force F acts on the lever arm at a distance 10 in from piston 1 as shown in the diagram. Assume the height difference between piston 1 and piston 2 is negligible. In the absence of friction, find the force F necessary to support the 591 lb weight (in units of lb.)

2006-12-01 09:16:05 · 3 answers · asked by Anonymous

can a maget be powerful enough to repel a bullet shot from a gun?

2006-12-01 08:53:52 · 6 answers · asked by advocat of funk 1

2006-12-01 08:50:27 · 8 answers · asked by Paul C 1

I am doing that for my science fair project &
I don't really know what to use- what type of
materials.

2006-12-01 08:48:59 · 10 answers · asked by Candy thunder 2

Who keeps track of time and how do we make sure our sources are reliable?

2006-12-01 08:39:09 · 6 answers · asked by tichothewolf 2

The smaller piston has a cross sectional area of 3.4 cm^2 and the larger piston has an area of 56 cm^2. What force F must be applied to the small piston to maintain the load of 82 kN at a constant elevation (in units of N)??

2006-12-01 08:37:10 · 1 answers · asked by Anonymous

the lighter elements would be layered deeper gradually down, the center being the atmosphere to almost vacum in the center(is it possible to create a model?)

2006-12-01 08:23:57 · 3 answers · asked by drozzie1 1

2006-12-01 08:18:17 · 3 answers · asked by tyreesesmum 2

Calculate the flow rate of blood (density = 1.15 g/cm^3) in an aorta with a cross-sectional area of 2.54 cm^2 if the flow speed is 48.9 cm/s (in g/s).

Assume the aorta branches to form a large number of capillaries with a combined cross-sectional area of 2720 cm^2, what is the flow speed in the capillaries (in cm/s)?

2006-12-01 08:17:47 · 1 answers · asked by Dee 4

A 0.440 kg ice puck, moving east with a speed of 3.04 m/s, has a head-on collision with a 0.950 kg puck initially at rest. Assume a perfectly elastic collision. Use east as the positive axis.

What is the speed of the lighter puck?

What is the speed of the heavier puck?

How would you answer this hard question?

2006-12-01 08:14:09 · 1 answers · asked by john c 1

A skydiver of mass m jumps from a hot air balloon and falls a distance d before reaching a terminal velocity of magnitude v. Assume that the magnitude of the acceleration due to gravity is g. What is the work Wd done on the skydiver, over the distance d, by the drag force of the air?
Express the work in terms of d, v, m, and the magnitude of the acceleration due to gravity g.
And Find the power Pd supplied by the drag force after the skydiver has reached terminal velocity v.

2006-12-01 07:55:47 · 1 answers · asked by Leah 2

or in motion at a constant speed along a straight line?

2006-12-01 07:55:31 · 5 answers · asked by Anonymous

goes back through time to stop her inventing her product. does the future change immeadiately as a result and so all the people that bought one never buy one and not even know of it's existence or does the future back date itself slowly and not change irrevocably untill it is impossible for her to invent the product at any time? is it possible that the people that she met as a result of her invention could also manipulate time to tell her that she did it in the first place..b4 her life was flipped?

2006-12-01 07:43:46 · 10 answers · asked by jayne beal 3

I tried using a trend line, but that doesn't have an option to fit to trig functions. I'm trying to create a laboratory exercise for my (college) students to do, and I'd rather have them use the computer to fit the data than do it by hand.

2006-12-01 06:48:54 · 1 answers · asked by kris 6

First if you have a Bible read Genesis 11:1-9. Then reverse the order of numbers to get 9-1-1-1. Or we could say 9/11/01. What is the chance that this is just random chance? What is the chance that it's intelligent design? I need intelligent answers not sarcasm.

2006-12-01 06:05:41 · 4 answers · asked by Roll'n Bluntz 2

2006-12-01 05:35:17 · 5 answers · asked by Anonymous

refract light in such a way as to appear to shapeshift? Is this even theoretically possible? If so, what kind of machine or object would do such a thing?

2006-12-01 05:35:09 · 4 answers · asked by Anonymous