Given the mass of a car, how fast it accelerates, and a forward directive force, how would i go about finding what the resistance force is? im trying to find an equation or something along those lines or maybe even a problem with these same variables.
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So, I've been reading about the Higgs because of all of this excitement lately with the LHC. I'm just a layman in physics but one thing I understood was that the Higgs field permeates all of space with a non-zero value. So...
Is this like how the vacuum fluctuations don't allow for space to be truly empty?
Does the same thing happen to the electromagnetic field so that nowhere in the universe is there zero charge?
This QM stuff is deep lol
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A bungee cord is 30.0 m long and, when stretched a distance x, it exerts a restoring force of magnitude kx. Your father-in-law (mass 94.0kg ) stands on a platform 45.0 m above the ground, and one end of the cord is tied securely to his ankle and the other end to the platform. You have promised him that when he steps off the platform he will fall a maximum distance of only 41.0 mbefore the cord stops him. You had several bungee cords to select from, and you tested them by stretching them out, tying one end to a tree, and pulling on the other end with a force of 410N .
When you do this, what distance will the bungee cord that you should select have stretched?
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Two small spheres are suspended by strings of length L = 1.20 m from a ceiling at points d = 3.20 m apart. They have equal mass of m = 8.00 kg and equal and opposite charge of q = 1.40E-4 C. Calculate the angle or angles the strings make from vertical at equilibrium.
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A diver jumps vertically off a 10m platform, reaches a maximum height of 1.5m above the platform, and lands in a swimming pool below. Three seconds after entering the water, her downward motion is stopped. (a) What was her average acceleration in the water? (b) Sketch her position versus time, velocity versus time, and acceleration versus time. Check for consistency between the graphs and explain why your graphs are consistent.
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A block of mass 15kg rests on a wedge (θ=26∘). The two objects move to the right in such a way that the block doesn't slide up or down the wedge. The coefficient of static friction between the block and the wedge is 0.35. What is the minimum acceleration of the two objects? What is the maximum acceleration of the two objects?
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How much force is needed from the bicep which is 5 cm from the joint to overcome a 59 kg weight in the hand if the .7m long forearm has a mass of 5kg and the elbow is flexed to 90 degrees?
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A diver of mass m drops from a board 6.00 m above the water's surface, as shown in the figure. Neglect air resistance.
(a) Use conservation of mechanical energy to find his speed 3.00 m above the water's surface.
(b) Find his speed as he hits the water.
(c) Suppose the diver vaults off the springboard, leaving it with an initial speed of 3.68 m/s upward. Use energy conservation to find his speed when he strikes the water.
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A 486 nm laser beam shines on a diffraction grating. 5 bright fringes are measured to be 60 cm apart at a Scren Distance of 1.327m. What is the grating constant in cm^-1
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A demented scientist creates a new temperature scale, the "Z scale." He decides to call the boiling point of nitrogen 0 ∘Z and the melting point of iron 1000 ∘Z.
A) What is the boiling point of water on the Z scale?
B) Convert 100 ∘Z to the Celsius scale.
C) Convert 100 ∘Z to the Kelvin scale.
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1.) If your hands are wet and no towel is handy, you can remove excess water by shaking them. Use Newton's laws to explain why doing this gets rid of water.
2.) Newton's third law tells us that if you push a box with a 15 N force, it pushes back on you with a 15 N force. HOw can you ever acclerate this box if it always pushes back with the same force you exert on it.
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An organ pipe is 151cm\; cm long. The speed of sound in air is 343 m/s. Part A: What are the fundamental and first three audible overtones if the pipe is closed at one end? What are the fundamental and first three audible overtones if the pipe is open at both ends? Express awnsers to 3 signiicant figures seperated by commas
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A 54-kg box is being pushed a distance of 7.1 m across the floor by a force Upper POverscript right-arrow EndScripts ? whose magnitude is 188 N. The force Upper POverscript right-arrow EndScripts ? is parallel to the displacement of the box. The coefficient of kinetic friction is 0.23. Determine the work done on the box by each of the four forces that act on the box. Be sure to include the proper plus or minus sign for the work done by each force. (a) WP = (b) Wf = (c) Wmg = (d) WN =
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|
he food calorie, equal to 4186 J, is a measure of how much energy is released when food is metabolized by the body. A certain brand of fruit-and-cereal bar contains 130 food calories per bar. |
Part A If a 72.0 kg hiker eats one of these bars, how high a mountain must he climb to "work off" the calories, assuming that all the food energy goes only into increasing gravitational potential energy? Express your answer in meters.
SubmitRequest Answer Part B If, as is typical, only 25.0 % of the food calories go into mechanical energy, what would be the answer to Part A? (Note: In this and all other problems, we are assuming that 100% of the food calories that are eaten are absorbed and used by the body. This is actually not true. A person's "metabolic efficiency" is the percentage of calories eaten that are actually used; the rest are eliminated by the body. Metabolic efficiency varies considerably from person to person.) |
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