Physics - December 2006

Hey! Please any help on this problem! I am really stuck on this one. Any help would be great.

An object moves uniformlly around a circular path of radius 16.0 cm, making one complete revolution every 1.65 s.

a) What is the translational speed of the object? (answer is in m/s)

b) What is the frequency of motion in hertz?
I already got the answer to this, .606 Hz

c) What is the angular speed of the object? (answer is in rad/s)

2006-12-06 08:54:11 · 1 answers · asked by Anonymous

How much force would be exerted to move a locomotive with one car attached?

The total weight of the locomotive and car is 200,000 lbs, and the coefficent of friction is .02" of the wheels on the rail. Assumed to be the coefficient is for static friction. Both the car and locomotive have 4 wheels in contact with the rail (8 total wheels).

2006-12-06 08:40:51 · 2 answers · asked by tiggs1515 3

2006-12-06 08:27:19 · 3 answers · asked by Anonymous

The anatomical structures in the lower leg and foot that are involved in standing on tiptoe, with the heel raised slightly off the floor so that the foot effectively contacts the floor only at point P. Assume distance a= 5.0 cm, distance b=15 cm, and the person's weight W= 900 N. Of the forces acting on the foot:
What are the:
(a) Magnitude of the force at point A from the calf muscle
(b) Direction of the force at point A from the calf muscle (up or down)
(c) Magnitude of the force at point B form the lower leg bones
(d) Direction (up or down) of the force at point B form the lower leg bones?

Answers:
(a) 2.7 kN
(b) Up
(c) 3.6 N
(d) Down

I don't know how they got these answer so if you can please show how.

2006-12-06 08:19:12 · 1 answers · asked by afchica101 1

A parachutist with a mass of 50 kg jumps out of an airplane at an altitude of 1.00 X 10^3 m (1000m). After the parachute deploys the parachutist lands with a velocity of 5.00 m/s using the work-kinetic energy theorem, find the energy that was lost to air resistance during this jump (G= 9.81 m/s^2)

A. 49300 J
B. 98800 J
C. 198000 J
D. 489000 J
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A child riding a bike has a total mass of 40.0 kg the child approaches the top of a hill that is 10 m high and 100m long at 5.0m/s. If the force of friction between the bicycle and the hill is 20N, what is the childs velocity at the bottom of the hill? (Disregard air resistance g= 9.81 m/s^2)

A. 5.0m/s
B. 10.0 m/s
C. 11m/s
D. Child stops before reaching the bottom.


I've worked these again and again and i cannot come up with an answer (for the first one i got D but it was a stretch) anyways if anyone could post the answer and the work i would greatly X a million appreciate it. thanks.

2006-12-06 08:17:49 · 1 answers · asked by strawberrylollipop12345 1

2006-12-06 08:12:20 · 3 answers · asked by lil_chea 2

2006-12-06 08:10:30 · 7 answers · asked by Molly 1

2006-12-06 07:41:07 · 7 answers · asked by Anonymous

Car engines, I think, are measured by the amount of torque created when the car's piston is pushed down. What I would like to know is how much force is created onto the piston when the fuel mix explodes.

2006-12-06 07:40:30 · 1 answers · asked by Anonymous

If a laser emits photons w/ wavelength of 542 nm with a rate of 1.5E19 photons/ sec what is the power, in watts, of the laser?
(----I guess I really just need to know how to convert photons to joules, since 1 Watt= 1 J/s. But how then does the wavelenght influence this answer? Any help is appreciated!)

2006-12-06 07:37:45 · 2 answers · asked by kas6945 1

Whereas if the particle were in a sphere, angular momentum *would* be conserved...?

2006-12-06 07:35:12 · 3 answers · asked by reba 1

pls, i need accurate answers

2006-12-06 07:30:41 · 6 answers · asked by amandac 3

2006-12-06 07:05:44 · 7 answers · asked by masooma 1

A lumberjack (mass = 98 kg) is standing at rest on one end of a floating log (mass = 280 kg) that is also at rest. The lumberjack runs to the other end of the log, attaining a velocity of +2.8 m/s relative to the shore, and then hops onto an identical floating log that is initially at rest. Neglect any friction and resistance between the logs and the water.
(a) What is the velocity of the first log just before the lumberjack jumps off? (Indicate the direction of the velocity by the sign of your answers.)
in m/s
(b) Determine the velocity of the second log if the lumberjack comes to rest on it.
in m/s

2006-12-06 07:04:09 · 2 answers · asked by Anonymous

A 5.00 kg ball (ball 1), moving to the right at a velocity of +3.00 m/s on a frictionless table, collides head-on with a stationary 8.00 kg ball (ball 2). Find the final velocities of the balls if the collision is as specified below.
(a) a completely elastic collision
ball 1
______ m/s
ball 2
______m/s
(b) a completely inelastic collision
ball 1
_______m/s
ball 2
______m/s

what is the difference between completly inelastic and elastic?

2006-12-06 06:41:43 · 3 answers · asked by lifewithgooli 1

2006-12-06 06:33:00 · 13 answers · asked by Alexander S 1

A 65kg kid runs at 5.0m/s , grabs a rope, and swings out over a lake. He releases the rope when his velocity is zero. a) what is the angle when he releases the rope? b) What is the tension in the rope just before he releases it? c) What is the maximum tension in the rope?

2006-12-06 06:18:47 · 1 answers · asked by Anonymous

2006-12-06 05:58:46 · 6 answers · asked by ganesh 1

2006-12-06 05:49:37 · 7 answers · asked by JAMES 4

Car 1 and 2 both weigh 1000kg,
Car 1 starts at top of 25m hill,
Car 2 starts on flat road,
Car 1 drives at 20m/s,
Car 2 drives at 30m/s, then comes to a stop.
Car 1 drives directly into 2 and the two cars end up moving in the same direction at 10m/s.

How much energy did Car 1 LOSE in the collision?
How much energy did Car 2 GAIN in the collision?

Please explain or write out the problem. Thank you.

2006-12-06 05:14:56 · 3 answers · asked by hanana 2

but what about gravitational energy??, this must be the most fundamental and crucial force in our universe as it gave rise to our current universe, gave rise to all galaxies, gave rise to all planets and will eventually destroy ALL again.
Once all that is, is once again in that singularity and all laws break down these forces will cease to be and (providing you believe in a cyclitic universe) it will all start again.
However gravity will always be there (potentially) as it is the mere effect one mass has upon another, even the singularity will have a gravitational effect on another body.
I think i have lost track of what i am asking, i do that a lot!!! i guess that i am saying that if you introduce a mass/ increase the mass of an existing body you will CREATE more gravitational energy, and the question is; does that contradict the 'you cannot create or destroy energy' law (if it is a law).

2006-12-06 05:04:41 · 7 answers · asked by tinyinnit 1

The longest "string" (a thick metal wire) on a particular piano is 2.0m long and has a tension of 300.0N. it vibrates with a fundamental freqency of 27.5 Hz.

what is the total mass of the wire?

2006-12-06 04:39:43 · 3 answers · asked by Trevor M 1

2006-12-06 04:10:41 · 3 answers · asked by robert j 1

I read that optically dense medium bends light rays towards the normal. Why does this happen? And why not away from the normal? Why does light slow down in optically dense media?

2006-12-06 03:59:22 · 2 answers · asked by astrokid 4

2006-12-06 03:54:44 · 4 answers · asked by robert j 1

2006-12-06 03:53:15 · 6 answers · asked by Ezzard S 1

2006-12-06 03:49:56 · 15 answers · asked by hannahmerry91 1

Tom has a mass of 31 kg, as Tom paddles, a force of 4.7 N acts in a direction due east. In addition, the current of water exerts a force of 1.1 N on Tom in a direction 55 degrees south of east. When these forces begin to act the initial velocity of the Tom is 2.9 m/s in a direction due east. Find the x-direction displacement of the Tom in 7 s.

Give your answer to 2 decimal places.

2006-12-06 03:34:29 · 4 answers · asked by wot_up_peeps2000 2

I have to write up a lab report after doing an experiment to determine the density of a common object (I chose a book). Now I need help finding the density. We know D=m/v and the book weighs 4 lbs. Its length is 10inches and width is 8 inches. Now using this information how would I find the mass and volume?
I also have to put the results into a chart, graph, or table but I don’t know how I would prepare that so any suggestions? Thanks.

2006-12-06 03:20:05 · 3 answers · asked by Fatima 1

The boiling point of water is lower when atmospheric pressure decreases. Theoretically, then, you could attach a suction pump to a pot and suck out the air above the water level, and the water would come to a boil faster, thereby saving energy. Do you see anything wrong with this argument?

2006-12-06 03:14:59 · 6 answers · asked by Anonymous