Physics - December 2007

i have a project to do and i can not find any where what the physics is in astrophysics..PLEASE HELP ME!!!!

2007-12-02 08:12:10 · 1 answers · asked by animals1077 3

I want answer on atomic level or even more basic.

2007-12-02 08:10:36 · 5 answers · asked by kerrigan 1

Two spherical balls are placed so that their centers are 2.6 m apart. The force between the two balls is 2.65 10-12 N. What is the mass of each ball if one ball is twice the mass of the other ball?

_______ kg (lighter ball)
_______ kg (heavier ball)

I also just wanted to say thank you to all the Canadians willing to help, you are so much more helpful then any Americans!!

2007-12-02 08:09:57 · 2 answers · asked by nbgolfer08 1

It is for my A2 physics coursework.

2007-12-02 08:06:41 · 1 answers · asked by bellerby648 2

breaking strenght of a cord is 44lbs. what's the max freq of revolution of a 8lb weight rotating in a horizontal circle of radius of 9ft.

2007-12-02 08:04:04 · 1 answers · asked by Anonymous

i made a program on my calculator for energy of a photon, because typing in 3 *10^8 and 6.63*10^-34 every second didn't seem very fun. but idk if its exactly right...so i want to check it here. what would the energy of a photon in joules be if it had a wavelength of 6*10^-7. i get 3.315 ^-19. doesnt seem right to me...seems to small.

2007-12-02 07:57:20 · 2 answers · asked by Anonymous

Does anyone know how to calculate Amplitude when given the velocity function and the mass on a simple harmonic motion with a spring problem?

The velocity equation is: V = (3.60 m/s)sin([(4.71s^-1)t - pi/2])
the springs mass is negligable and there is a .500 kg mass on the end of the spring.

please help. I am so stuck.

2007-12-02 07:57:18 · 2 answers · asked by SpaceTrekkie 3

A 9.00kg hanging object is connected, by a light, inextensible cord over a light, frictionless pulley, to a 5.00kg block that is sliding on a flat table. Taking the coefficient of kinetic friction as 0.200, find the tension in the string.

thank u

2007-12-02 07:49:14 · 2 answers · asked by xmoonlight_88 1

A 27.1 kg box initially at rest is pushed 2.56 m along a rough, horizontal floor with a constant applied horizontal force of 129.712 N.
The acceleration of gravity is 9.8 m/s2.

(A) If the coefficient of friction between box and floor is 0.418, find the work done by the applied force. Answer in units of J.

(B) Find the work done by the friction in units of J.

(C) Find the change in kinetic energy of the box in units of J.

(D) Find the the final speed of the box in units of m/s

please and thank you to anyone helps, it's truly appreciated :)

2007-12-02 07:47:05 · 3 answers · asked by Catalina 2

I'm not sure how to solve for the velocity of a projectile when the initial and final points are not on the same horizontal level. Any general tips, or an explanation of the answer to the following question would be appreciated. Thanks.

Fizzicks has climbed to a ledge 270 metres above the base of a mountain. Hamilton, standing on level ground, uses his slingshot to send a canteen to Fizzicks, a horizontal distance of 390 metres away. The canteen is launched at an angle of 70 degrees to the horizontal. What should be the launch speed of the canteen?

2007-12-02 07:42:13 · 3 answers · asked by Anonymous

2007-12-02 07:28:21 · 2 answers · asked by Monkjitsu 1

2007-12-02 07:27:56 · 1 answers · asked by Monkjitsu 1

If a person who weighs 612N sits in a hammock 3m long and sags 1m below the point of support, what force is exerted on the ropes suporting the hammock. Please help me by showing how you got that answer

2007-12-02 07:19:52 · 2 answers · asked by Anonymous

A sled of mass 50 kg is pulled along snow-covered, flat ground. The static friction coefficient is 0.30, and the sliding friction coefficient is 0.10. What force is needed to get the sled moving? Then, what force is needed to keep the sled moving at a constant velocity? And once moving, what total force must be applied to the sled to accelerate it 2.0 m/s2?

2007-12-02 07:03:55 · 2 answers · asked by Anonymous

Bicycle and rider weigh 250 Lbs
Force applied at the pedal is 25 Lbs
Wheel Diameter is 20"
Pedal length from center of drive sprocket is 10"
Drive pedal sprocket has 20 teeth
Idle driven sprocket has 35 Teeth
What is the force applied by the tire on the road?
What is the acceleration?
What is the velocity after 20 seconds?
What is the coefficent of friction supposed to be for this to happen?
Must explain the steps

2007-12-02 06:53:26 · 1 answers · asked by calcstress 1

im in 9th grade physics...
in the problem you have to find the acceleration due to gravity on neptune... it tells you the mass of the planet and the radius.
what equation do you use??
thanks!

2007-12-02 05:44:58 · 5 answers · asked by hcogirl14 4

A dancer lifts his 53.6 kg partner straight
up off the ground a distance of 0.373 m before
releasing her.
The acceleration of gravity is 9.8 m/s2

If he does this 22 times, how much work has
he done? Answer in units of J.

thank you in advance for helping ^_^

2007-12-02 05:42:20 · 3 answers · asked by Catalina 2

2007-12-02 05:30:07 · 3 answers · asked by Mike G 2

a) 6.90 x 10(-7)
b) 2.88 x 10(-19)
c) 4.35 x 10(14)
d) 1.45 x 10(-10)
e) 1.04 x 10(27)

2007-12-02 05:30:07 · 3 answers · asked by maybe71400 1

Why does the doppler effect occur only if the sound-emitting object is moving relative to the listener?

2007-12-02 05:27:58 · 2 answers · asked by Anonymous

If a vibrating system has total energy E_0, what will its total energy be (in terms of E_0) if you double the amplitude of vibration?

If you want to triple the total energy of a vibrating system with amplitude A_0, what should its new amplitude be (in terms of A_0)?

2007-12-02 05:23:20 · 1 answers · asked by SweetMandy01234 2

How far (in terms of A) is this mass from the equilibrium position of the spring when the elastic potential energy equals the kinetic energy?

2007-12-02 05:20:30 · 2 answers · asked by SweetMandy01234 2

This question is really frustrating me. I would really appreciate help. Thanks!
A flywheel turns through 52 rev as it slows from an angular speed of 2.6 rad/s to a stop
(a) Assuming a constant angular acceleration, find the time for it to come to rest.
(b) What is its angular acceleration?
(c) How much time is required for it to complete the first 26 of the 52 revolutions?

Also, if you could show your work, that would be great. Thanks.

2007-12-02 05:20:01 · 1 answers · asked by Anonymous

energy level of a hydrogen atom

a) 0.872
b) -1.55
c) 1.55 x 10(-19)
d) 2.42
e) 2.42 x 10(-19)

2007-12-02 05:12:11 · 3 answers · asked by maybe71400 1

A uniform, solid disk with mass m and radius R is pivoted about a horizontal axis through its center. A small object of the same mass is glued to the rim of the disk.

If the disk is released from rest with the small object at the end of a horizontal radius, find the angular speed when the small object is directly below the axis.

Express your answer in terms of the variables m, R and appropriate constants.

2007-12-02 04:59:19 · 3 answers · asked by Anonymous

a stone is dropped from rest into a well. the sound of the splash is heard exactly 2.00 s later. Find the depth of the well if the air temperature is 10.0 degrees Celsius.

2007-12-02 04:53:38 · 3 answers · asked by Mika 2

A. The forces on it are balanced
B. There is a constant resultant force acting
C. The resultant force acting on it decrease with time
D. The resultant on it increase with time

Explanation please...

2007-12-02 04:34:19 · 3 answers · asked by Flamezz 5

2007-12-02 04:24:02 · 2 answers · asked by Anonymous

Imagine an object with charge Q moving along the ground with speed v through a uniform upward magnetic field of strength B. There is a force of strength QvB on the charged particle. Now imagine an observer moving at the same velocity as the particle. To that observer, v=0. But according to Newton and Galileo, the particle must experience the same force F as before. How can this be? The moving observer sees v=0, so can there be a magnetic force? If not, what kinds of forces can there be instead? If yes, how do you resolve the velocity problem?

2007-12-02 04:03:05 · 5 answers · asked by never_too_clever 1

Uranium (92 protons) decays by emitting an alpha particle and two beta particles; which element is produced after those three decays?

2007-12-02 04:00:42 · 3 answers · asked by A M 2