[Selected]: All categories ➔ Science & Mathematics ➔ Physics
In this context what are the roles of variable stars, supernovae, the Tully-Fisher relation and the Hubble flow.
2007-12-06 10:51:00 · 1 answers · asked by DoubleO 7 1
2007-12-06 10:46:10 · 3 answers · asked by pyarali2 1
This one problem has been bothering me, and I can't get it.
Can anyone help?
"A skier is pulled up a slope at a constant velocity by a tow bar. The slope is inclined at 25.0º with respect to the horizontal. The force applied to the skier by the tow bar is parallel to the slope. The skier's mass is 55.0 kg, and the coefficient of kinetic friction between the skis and the snow is 0.120. Find the magnitude of the force that the tow bar exerts on the skier."
2007-12-06 10:42:58 · 1 answers · asked by Anonymous
i really need help
please!
2007-12-06 10:30:35 · 2 answers · asked by Anonymous
It goes point A to R1 to +- battery (V1) to R2 to -+ battery(V2) to point B. The current flows from A to B.
If a current I=5 A exists between points a and b, R1=7 Ω, R2=8 Ω, V1=16 V, and V2=3 V,the voltage difference Va−Vb is
2007-12-06 10:08:41 · 1 answers · asked by bach454396 1
Fireworks at Memorial Park are fired at an angle of 82 degrees with the horizontal. The technician expects them to explode about 300 feet in the air 4.8 seconds after they are fired. Find the initial velocity of a shell fired from the ground.
2007-12-06 10:02:26 · 1 answers · asked by BadCompany 1
The rocket is supposed to release a parachute 300 feet in the air, 7 seconds after liftoff. They are firing the rocket at a 78 degree angle from the horizontal. Find the initial velocity of the rocket.
2007-12-06 09:58:17 · 1 answers · asked by BadCompany 1
A 20-kg girl slides down a playground slide that is 3.2 meters high. When she reaches the bottom of the slide, her speed is 1.3 m/s. (a) How much energy was dissipated by friction? (b) If the slide is inclined at 20 degrees, what is the coefficient of friction between the girl and the slide?
2007-12-06 09:40:19 · 1 answers · asked by allaboutfun 1
I understand Audio feedback is caused by a "looped signal", that is, a signal which travels in a continuous loop. Most commonly a microphone feeds a signal into a sound system, which then amplifies and outputs the signal from a speaker, which is picked up again by the microphone. All of that I get.
But my question is, what causes the loud squealing noise? Shouldn't it just amplify the sound even more?
Thanks!
2007-12-06 09:24:32 · 1 answers · asked by Hey now... 2
A roller-coaster car comes to a near-stop at the top of a hill 40 m in height. It then goes roaring down the hill, and rebounds up a shorter hill 16 m in height. If friction's effects can be ignored, at the top of the 16-m hill its speed will be ___.
I know the answer is about 21 m/s, but I'd appreciate it if someone could explain how to arrive at that answer. Thanks.
2007-12-06 09:23:08 · 3 answers · asked by Anonymous
2007-12-06 09:03:28 · 3 answers · asked by Anonymous
A .3-kg puck, initially at rest on a frictionless horizontal surface, is struck by a .2-kg puck that is initially moving along the x-axis witha a velocity of 2m/s. After the collision, the .2-kg puck has a speed of 1 m/s at an angle of Θ53 degrees to the positive x-axis. (a)Determine the velocity of the .3-kg puck after the collision. (b) Find the fraction of kinetic energy lost in the collision.
2007-12-06 09:03:27 · 2 answers · asked by kard5hark11 2
Is it possible to stack up to 6 2X magnification fresnel lenses to increase magnification to 64X? (if properly spaced/focused) I am not trying to magnify an image, only magnify light for an experiment with a solar panel.
2007-12-06 08:59:50 · 2 answers · asked by neverknew 2
2007-12-06 08:46:41 · 9 answers · asked by winky 2
What is meant by saying that carbon-12 is stable?
an also why is the number of nuclei is 25957922978 why this suggest that the salt is heavily contaminated?
2007-12-06 08:46:32 · 1 answers · asked by Anonymous
Assume the fence is the same hieght as the pitch and find the velocity of the ball when it left the bat. neglect air resistance.
i got 31.6 approximately but my teacher says im wrong and the books ays im right am i??
2007-12-06 08:44:07 · 1 answers · asked by bigredtank87 1
2007-12-06 08:33:13 · 10 answers · asked by mileandrei 2
2007-12-06 08:11:24 · 6 answers · asked by Anonymous
Ok, ill type it out how it is with the information I got from it. It's obsurd how teachers can give such a complex question at the Physics 11 level!
Tim tries to crush a 0.58kg basketball but is only able to compress it by 1.5cm when a force of 50N is applied.
a) Spring constant?
b) When he throws it against the floor it is compressed 3.4cm. How high will it bounce?
I got Force.. which is F=kx F = (3333.33N/m)(0.034m) thus F=113.33322N
I got accel.. which is F=ma A = 113.33322N / 0.58Kg thus A = 195.402m/s2
Now without using anything that has to deal with energy and simple harmonic motion.. I have to somehow get how high the ball bounces with Kinematics.. but I know Vf = 0 of the ball but not Vo.. hmmm help me out people around the world! Thankyou
Love, Michael.
2007-12-06 07:34:19 · 1 answers · asked by lust_san 1
Using a force platform it's been found that when people jump straight up as high as they can they exert a net downward force for much of the time equal to about 2.3 times their weight. Approximately what acceleration do they achieve?
2007-12-06 07:30:58 · 1 answers · asked by Anonymous
Just need to know for my metal tech teacher.
2007-12-06 07:23:42 · 5 answers · asked by Stephen 2
First of all, I want this to be theoretical. I know we are perhaps centuries from this sort of technology.
But could it be possible? And how would the sciene behind it work? I'm talking about the sort of thing where you step into a Jetsons-like tube, press a button, and vanish. You then materialize elsewhere.
2007-12-06 07:07:36 · 4 answers · asked by Anonymous
Someone asks: Can a bullet have the same momentum as a truck? You would be right if you said which one or more of the following:
a. Yes, and if so they will both impart the same impulse in a 2-to-1 interaction.
b.No, because the bullet's mass is so much smaller.
c.Yes, by having a higher velocity than the truck.
d.Yes, but only if the impulse imparted to the bullet was larger.
2007-12-06 06:57:45 · 4 answers · asked by Nicky 1
A 3.0 kg block is attached to a string that is wrapped around a 2.0 kg, 4.0-cm-diameter hollow cylinder that is free to rotate. The block is released 1.0 m above the ground.
Also need to:
Use conservation of energy to find the speed of the block as it hits the ground.
2007-12-06 06:50:47 · 2 answers · asked by Michelle W 1
If it was possible to drill a tunnel through the earth from one end to the other and jump into it, what would happen once we reach the core of the earth? Would we fall to the side, float motionless or what? Since gravity pulls you to the center, what would happen once we reached the center if jumping from either end of the tunnel will make you fall..... ?
Answer that......
2007-12-06 06:46:55 · 7 answers · asked by DeFoNLooK 1
how can u get to .. R = [Vi^2(sin2θ)]/g ?
2007-12-06 06:44:06 · 3 answers · asked by Dani 3
A 10 g bullet is fired into a 10 kg wood block that is at rest on a wood table. The block, with the bullet embedded, slides 5.0 cm across the table. The coefficient of kinetic friction for wood sliding on wood is 0.20.
2007-12-06 06:32:19 · 1 answers · asked by mnhw2 1
A 10 g bullet is fired into a 10 kg wood block that is at rest on a wood table. The block, with the bullet embedded, slides 5.0 cm across the table. The coefficient of kinetic friction for wood sliding on wood is 0.20.
2007-12-06 06:31:42 · 1 answers · asked by mnhw2 1
A cylinder contains 270 L of hydrogen gas (H2 at 0.0 °C) and a pressure of 10 atm. How much energy is required to raise the temperature of this gas to 25°C? Units in kJ
2007-12-06 06:25:17 · 1 answers · asked by Eli D 1
what about when it passes from water to air?
2007-12-06 06:17:29 · 1 answers · asked by Taaay[: 2
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