Physics - October 2007

2007-10-29 14:17:51 · 1 answers · asked by Yahoo 4

are on the highway and its a really hot day and you see those wavy waves.. What are those and what are some facts about them?

Cooking on the grill
above a heater
Highway...

2007-10-29 14:05:04 · 9 answers · asked by ♦Its•Possible•But•Not•Logical♦ 3

If, theoretically, a locomotive of 3000 kg is pulling a freight car of 5000 kg, with a coefficient of static friction of 0.8 and an effective coefficient of friction of 0.2 and the entire train (locomotive + car) is accelerating to the right at 0.5 m/s^2, What is the magnitude of the force creating this acceleration? What is the object exerting this force on the train?

2007-10-29 14:02:13 · 1 answers · asked by katie m 1

Ahhhhhhhhh I'm stuck at this physics problem! I thought I at least knew tension is 9.8 * 7100 but thats not right! please help, thank u!

A cubic meter of some material has a mass of 7100 kg. The block of material is lowered into a lake by a strong cable until the block is completely submerged. (Free fall diagram can be made).
Find the buoyant force on the block and the tension in the cable (answers in N)

2007-10-29 13:55:27 · 1 answers · asked by Anonymous

2007-10-29 13:48:35 · 2 answers · asked by Cedric R 1

Please, put it in terms that an ordinary dumb person can understand!

2007-10-29 13:41:50 · 2 answers · asked by Anonymous

A charged particle under acceleration should radiate energy. Since an electron revovling around the nucleus constantly changes diraction, it is constantly acceleration and it should be constantly losing energy. As it loses energy, shouldn't it be getting closer to the nucleus and eventually collide with it? What is wrong with this?

2007-10-29 13:19:09 · 2 answers · asked by ashlee052690 1

2007-10-29 13:03:43 · 2 answers · asked by Anonymous

2007-10-29 12:48:13 · 2 answers · asked by ashlee052690 1

A person is making homemade ice cream. She exerts a force of magnitude 20 N on the free end of the crank handle, and this end moves in a circular path of radius 0.32 m. The force is always applied parallel to the motion of the handle. If the handle is turned once every 1.4 s, what is the average power being expended?
W

2007-10-29 12:43:06 · 1 answers · asked by Anonymous

In an action-adventure movie, the hero lifts the 91-kg villain straight upward through a distance of 1.0 m in 0.52 s at a constant speed. What power does the hero produce while doing this?
W

2007-10-29 12:42:29 · 1 answers · asked by Anonymous

A basketball player makes a jump shot. The 0.650-kg ball is released at a height of 1.90 m above the floor with a speed of 8.00 m/s. The ball goes through the net 3.10 m above the floor at a speed of 3.90 m/s. What is the work done on the ball by air resistance, a nonconservative force?
J

2007-10-29 12:41:56 · 1 answers · asked by Anonymous

A 0.60 kg basketball is dropped out of the window that is 6.2 m above the ground. The ball is caught by a person whose hands are 1.8 m above the ground. How much work is done by the ball by its weight?
25.872 J
What is the gravitational potential energy of the basketball, relative to the ground when it is released?
36.456 J
What is the gravitational potential energy of the basketball when it is caught?
J
How is the change (PEf - PE0) in the ball's gravitational potential energy related to the work done by its weight?

2007-10-29 12:41:20 · 1 answers · asked by Anonymous

I went to put a glass in the microwave the other day and my husband stopped me saying that you can't put glass in a microwave as the glass will explode. I find it hard to believe that in 7 years of owning a microwave I have never put a glass in there so I am thinking I must of in the past but it didn't explode. Does anyone know the right answer?

2007-10-29 12:27:33 · 4 answers · asked by Anonymous

Two objects of masses m and 4m are moving toward each other along the x-axis with the same initial speeds v0 = 45.0 m/s. The object with mass m is traveling to the left, and the object with mass 4m is traveling to the right. They undergo an elastic glancing collision such that mass m is moving downward after the collision at right angles from its initial direction.
(a) Find the final speeds of the two masses.
(b) What is the angle from its initial direction of motion at which the mass 4m is scattered?

2007-10-29 11:44:28 · 1 answers · asked by Anonymous

rocket launched upward with initial speed of 50m/s and constant acceleration of 2m/s2 with altitude of 150 m

2007-10-29 11:39:53 · 1 answers · asked by Don 1

As science becomes more sophisticated, researchers develop coherent theories about the workings of matter and energy. These ideas were not always on the right track, despite extensive initial evidence. For example, "the opinion of many scientists was that heat energy and work energy were different types of universal fluids that flowed from object to object as they interacted. They also believed that certain interactions required no exchange of energy at all." While these theories could be explained through evidence available at the time, they were eventually proven wrong by further discoveries. Science is not fact, but rather our attempt to best explain something with the limitations we have with regards to technology, etc.

2007-10-29 11:19:44 · 6 answers · asked by jay k 6

A wheel of radius 0.20 m is mounted on a frictionless horizontal axis. The rotational inertia of the wheel about the axis is 0.050 kg · m2.A massless cord wrapped around the wheel is attached to a 2.0 kg block that slides on a horizontal frictionless surface. If a horizontal force of magnitude P = 3.0 N is applied to the block as shown in Fig. 11-35, what is the magnitude of the rotational acceleration of the wheel? Assume that the string does not slip on the wheel.

2007-10-29 11:09:33 · 1 answers · asked by hhhwwf13 1

2007-10-29 10:58:24 · 9 answers · asked by lee s 1

A 49.0 kg person holding two 0.850 kg bricks stands on a 2.10 kg skateboard. Initially, the skateboard and the person are at rest. The person now throws the two bricks at the same time so that their speed relative to the person is 21.8 m/s. What is the recoil speed of the person and the skateboard relative to the ground, assuming the skateboard moves without friction?

2007-10-29 10:57:31 · 1 answers · asked by Amber G 2

An observer in a second balloon, positioned at 600m above the ground views the same object at angle of depression of 28. Calculate the distance between two balloons.

2007-10-29 10:55:55 · 2 answers · asked by yeshila 1

some people say they will hit the ground at the same time,because there is no air resistance on the moon,so what about the mass of the objects can it be nigligible?

2007-10-29 10:49:31 · 7 answers · asked by sktany12 2

2007-10-29 10:49:09 · 2 answers · asked by Dov F 1

To move a large crate across a rough floor, you push on it with a force F at an angle of 21°, below the horizontal. Find the acceleration of the crate, given that the mass of the crate is m = 30 kg, the applied force is 325 N and the coefficient of kinetic friction between the crate and the floor is 0.46.


Thanks a lot again.

2007-10-29 10:40:17 · 1 answers · asked by acousticplaya90 1

A 1250 N uniform beam is attached to a vertical wall at one end and is supported by a cable at the other end. A W = 1980 N crate hangs from the far end of the beam.

a) Calculate the magnitude of the tension in the wire.


(b) Calculate the magnitude of the horizontal and vertical components of the force that the wall exerts on the left end of the beam.
Fx =
Fy =

Here is a drawing
http://www.webassign.net/CJ/p9-66alt.gif

there are so much information in this problem that I don't know where to start. Any help would be greatly appreciated.

Thank You.

2007-10-29 10:29:36 · 1 answers · asked by Anonymous

A house painter is standing on a uniform, horizontal platform that is held in equilibrium by two cables attached to supports on the roof. The painter has a mass of 77 kg and the mass ofthe platform is 19.6 kg. The distance from the left end of the platform to where the painter is standing is d = 2.0 m and the total length of the platform is 4.9 m.
a) How large is the force exerted by the left-hand cable on the platform?
b) How large is the force exerted by the right-hand cable?

A uniform diving board, of length 5.0 m and mass 55 kg, is supported at two points; one support is located 3.4 m from the end of the board and the second is at 4.6 m from the end (see the figure below). What are the forces acting on the board due to the two supports when a diver of mass 63 kg stands at the end of the board over the water? Assume that these forces are vertical. [Hint: In this problem, consider using two different torque equations about different rotation axes.
Left support ____
Right support

2007-10-29 10:20:19 · 1 answers · asked by Pr0ject 1

.............___|_A_|_---------O--|
P <-----|_B_40kg_|--------O..|
it's a single pulley connected to the two blocks and connected by its center to the wall. Block A is on top of block B with block B being pulled straight to the left (P)
u = 0.2 at all contact surfaces (neglect pulley friction)
A is 80kg
Determine the magnitude of force P required to move the 40kg plate B to the left.

2007-10-29 10:18:51 · 1 answers · asked by Anonymous

A rotational axis is directed perpendicular to the plane of a square and is located as shown in the drawing. Two forces, 1 and 2, are applied to diagonally opposite corners, and act along the sides of the square, first as shown in part a and then as shown in part b of the drawing. In each case the net torque produced by the forces is zero. The square is one meter on a side, and the magnitude of 2 is 3 times that of 1. Find the distances a and b that locate the axis. Note that a and b are not drawn to scale.

I'm not sure where to begin with this question. Can someone give me some tips? I'd greatly appreciate it.

Thanks.


Here is an image

http://www.webassign.net/CJ/p9-10.gif

2007-10-29 09:40:31 · 1 answers · asked by Anonymous

A solid circular disk has a mass of 1.2 kg and a radius of 0.19 m. Each of the three identical thin rods has a mass of 0.12 kg. The rods are attached perpendicularly to the plane of the disk at its outer edge to form a three-legged stool.Find the moment of inertia of the stool with respect to an axis that is perpendicular to the plane of the disk at its center. (Hint: When considering the moment of inertia of each rod, note that all of the mass of each rod is located at the same perpendicular distance from the axis.)


How would you go about doing this?

I'd appreciate any help.

2007-10-29 09:35:49 · 1 answers · asked by Anonymous

Please provided details, answers, and how you got to your answer.

Problem 1:
A ball is dropped from the top of a building and hits the ground 4.6 seconds later. How high is the building?

Problem 2:
A cannon fires an object with an inital velocity of 40 m/s at an angle of 25 degrees. How long is the object in the air? What is the maximum height of the object? What is the range of the object?

Problem 3:
A projectile remains in the air for 6.0 seconds after it is fired. The horizontal component of its velocity is 100 m/s. How far did the object move forward before it hit the ground? How long after firing did the projectile reach it's maximum height? How high up did the projectile go?



Thank you. I am studying for a test and really need help

2007-10-29 09:15:58 · 1 answers · asked by Courtney B 1