Physics - October 2006

How long does light take to travel a distance of one light-year?

2006-10-17 11:33:33 · 17 answers · asked by hayzman22 1

If you were decelerating, but you doubled your initial speed...what does this do to the time and distance it takes to stop my car?

To do this would I just plug in random numbers?


I know i'm supposed to double the time but I don't understand WHY!!!

2006-10-17 11:11:40 · 3 answers · asked by beast 1

The car is uniformly accelerated during the entire time. What net force is exerted on it?

Please help.

2006-10-17 10:47:48 · 3 answers · asked by swimmertommy 1

PROBLEM #1:
Desert Sand is very hot in the day and very cool at night. What does this tell you about its specific heat?

PROBLEM #2:
What determines whether an object at a given time is a net absorber or a net emitter? Why?

When you answer this problems, please, specify which answer is for what.

2006-10-17 10:42:44 · 2 answers · asked by Gordito 1

After the Big Bang which to my understanding started as a single spot smaller than the dot at the end of this sentence and then has expanded to the current size of the universe. With my simple logic I would assume that the expansion would leave a every growing empty space at the center of the universe but I have never heard any one speak of it.

2006-10-17 10:42:08 · 6 answers · asked by the_news_junky 2

After a snowstorm a girl and a boy decide to have a snowball fight. The girl uses a slingshot to shoot snowballs at the boy. Assume that the girl fires each snowball at an angle (-) from the ground and that the snowballs travel with an initial velocity of v0. HELP! I have no clue how to figure this one out!

2006-10-17 10:41:55 · 4 answers · asked by taintedlove463 1

Will a bag holding 15 kg of groceries that is lifted from the checkout conunter at an acceleration of 7.0 m/s^2 hold?

I need help putting the problem into an equation.

2006-10-17 10:40:41 · 1 answers · asked by swimmertommy 1

QUESTION #1:
Is cold the opposite of thermal energy or the lack of it? Why?

QUESTION #2:
Does a substance that heats up quickly have a high or a low specific heat capacity? Why?

QUESTION #3:
Why can't you establish whether you are running a high temperature by touching your own forehead?

When answering this ones, please, specify which answer is for what question. Thanks

2006-10-17 10:39:07 · 2 answers · asked by Gordito 1

Block 1 has mass M, block 2 has 2M, and block 3 has 2M. What is the coeffieent of kinetic friction between block 2 and the table?

Answer: Let the tensions of on the strings connecting m2 and m3 be T23, and that connectiong m2 and m1 be T12, respectively. Applying Newton's second law with FN= m2g in this case to the system we have

m3g - T = m3a
T23 - µk m2g - T12 = m2a
T12 - m1g = m1a

Adding up the three equations and using m1 = M, m2 = m3 = 2M, we obtain

2Mg- 2µk Mg - Mg = 5 Ma

With a = 0.5m/s^2 this yields µk = 0.372. Thus, the coefficient of kinetic friction is roughly µk = 0.37

If you can, please explain and show haw they solved for µk because I didn't understand that last part. Thank you

2006-10-17 10:38:03 · 1 answers · asked by gods1princesschanel 1

I need need with the following problems.

a. find the average acceleration of the dragster during this time interval.

b. what is the magnitude of the average net force on the dragster during this time?

c. assume that the driver has a mass of 68kg. What horizontal forces does the seat exert on the driver?

Especially the last part.

2006-10-17 10:37:08 · 1 answers · asked by swimmertommy 1

Is in Physics

2006-10-17 10:33:31 · 4 answers · asked by Gordito 1

with a second sphere that is initially at rest. The composite system moves with a speed equal to one-third the original speed of 2.66 kg sphere.

What is the mass of the second sphere (in units of kg).

2006-10-17 10:30:09 · 1 answers · asked by Dee 4

A 2.00 kg block is being pushed against a spring with negligible mass and force constant k=400 N/m, compressing it 0.22 m. When the block is released, it moves along a frictionless, horizontal surface and then up a frictionless inlcine with slope 37 degrees.

What is the speed of the block as it slides along the horizontal surface after having left the spring?

How far does the block travel up the incline before starting to slide back down?

2006-10-17 10:16:48 · 2 answers · asked by fender_tri 1

What type of magnet does a bicycle dynamo use?
How does the magnet spin?

2006-10-17 10:14:01 · 3 answers · asked by Queenie 4

A river flows due east at 1.70 m/s. A boat crosses the river from the south shore to the north shore by maintaining a constant velocity of 9.70 m/s due north relative to the water.
a. What is the velocity of the boat as viewed by an observer on shore?
b. If the river is 330 m wide, how far downstream has the boat moved by the time it reaches the north shore?

How do you solve this problem?

2006-10-17 10:03:35 · 3 answers · asked by justinegunderson 1

2006-10-17 10:01:55 · 7 answers · asked by Romeo 2

Initial speed of 2.0 m/s
up a 24.0° incline
mass is 14 kg
Coefficient of kinetic friction is 0.20.

How far up the incline does it move? In m?

2006-10-17 08:46:52 · 3 answers · asked by activegirl 1

2006-10-17 08:45:28 · 4 answers · asked by gasguzlr76 2

2006-10-17 08:39:13 · 3 answers · asked by Anonymous

2006-10-17 08:14:22 · 13 answers · asked by Anonymous

and an object could travell in two directions at the same time.
Electrons seem to do that.
If we lived in 2d space we would have no idea what up and down is, mabe our unidirectional time limits us and we have no idea what travelling in two directions at the same time is.
What do you think?

2006-10-17 07:47:41 · 6 answers · asked by Yahoo! 5

2006-10-17 07:38:03 · 5 answers · asked by BOISESTATEFAN208 1

2006-10-17 07:14:57 · 2 answers · asked by nandu 1

2006-10-17 06:47:03 · 1 answers · asked by L M 1

If you stand on a bathroom scale, the spring inside the scale compresses 0.60mm, and it tells you your weight is 710 N. Now if you jump on the scale from a height of 1.0m, what does the scale read at its peak?

2006-10-17 06:46:54 · 1 answers · asked by Anonymous

A pump is to lift 18.0kg of water per mminute through a height of 3.60m. What output rating (watts) should the pump motor have?

2006-10-17 06:45:36 · 20 answers · asked by Anonymous

At an accident scene on a level road, investigators measure a car's skid mark to be 88m long. THe accident occurred on a rainy day, and the coefficient of kinetic friction was estimated to be 0.42. Use these data to determine the speed of the car when the driver slammed on (and locked) the breaks. (Why does the car's mass not matter?)

2006-10-17 06:44:24 · 7 answers · asked by Anonymous

If the KE of an arros is doubled, by what factor has its speed increased?
If its speed is doubled, by what factor does its KE increase?

2006-10-17 06:42:29 · 4 answers · asked by Anonymous

2006-10-17 05:48:29 · 10 answers · asked by brittenybryant 1

2006-10-17 05:44:37 · 3 answers · asked by brittenybryant 1