A novelty collision device known as the executive toy consists of five identical metal balls. When one ball swings in, after multiple collisions, one ball swings out at the other end of the row of balls. When two balls swing in, two swing out; when three swing in, three swing out, and so on-always the same number out as in. Suppose that one ball, with mass m, swing in and collide with the next ball with a velocity v. Why don’t two ball swing out at the other end with a velocity of v/2? Clearly establish the reasoning and physical principles to receive full credit.
Can someone explain to me what laws are being used here and how it relates to the question? Thank you.
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What's the Fourier transform of the following equations:
1) f(t)=1/(t^2+a^2) a is a constant
2) e^[-absolute value(t)/a]*cos(b*t) a and b are constants
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Coulomb's Law
1. What evidence do you see that Newton's third law applies to electrostatic forces?
2. Electric force is a force of attraction or repulsion between objects based on their charges and their distance apart.
(a) When is the electric force attractive?
(b) When is the electric force repulsive?
3. Explain how electric forces are like gravitation forces and how they differ.
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1: A car, A, is stationary with the engine running. A second car, car B, passes car A at a constant speed of 12 m/s. at this moment car A accelerates at 0.5 m/s2.
A: Sketch the two events on the time vs position graph.
B: How far down the road does car A catch car B.
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A chandelier with mass mmm is attached to the ceiling of a large concert hall by two cables. Because the ceiling is covered with intricate architectural decorations (not indicated in the figure, which uses a humbler depiction), the workers who hung the chandelier couldn't attach the cables to the ceiling directly above the chandelier. Instead, they attached the cables to the ceiling near the walls. Cable 1 has tension T1T1T_1 and makes an angle of θ1θ1theta_1 with the ceiling. Cable 2 has tension T2T2T_2 and makes an angle of θ2θ2theta_2 with the ceiling.
Find an expression for T1T1T_1, the tension in cable 1, that does not depend on T2T2T_2.
I have been trying to answer this one question and can't seem to get a correct order if someone can please help me.
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Imagine that you are in a rowboat with a crate of fruit. You are having a lovely time with our crate, but when you row the boat to the middle of the pond, you decide to drop the crate off the boat (without capsizing the rowboat) and watch it sink to the bottom of the pond. Assuming the depth of water in the pond could be measured, explain in detail (using mathematical and diagrammatical support) the relationship between the depth of the water when the crate was in the rowboat and the depth of the water after the crate has sunk to the bottom of the pond. Note: mathematical does not imply the use of numbers.
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7. A cue ball traveling horizontally at 2.5 m/s strikes a stationary 8-ball, causing the 8-ball to travel at a 30◦ angle with respect to the horizontal. If the two have the same mass, (a) What are the speeds of the cue and 8-ball post-collision? (b) Using your results, indicate what kind of collision occurred. You must back up your conclusion using your results.
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Two methods are used to generate 1 GWhe of electricity: (1) burning coal with a generation efficiency of 30% and (2) burning MSW with an efficiency of 25%. (The energy content of coal is 31 MJ/kg.) For MSW generation, assume an energy content of 10 MJ/kg and a total net energy requirement of 5000 MJ/tonne for collection and transportation, which is provided by burning fossil fuels at 20% efficiency. The MSW consists of 50% carbon-neutral organic material and 50% fossil fuel–derived material. (The energy content and the density of petroleum is 35 MJ/kg and 0.72 kg/L, respectively.) Compare the relative contributions to greenhouse gas emissions for these two methods. Ignore any effects of possible carbon sequestration.
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Calculate the enthalpy of fusion (KJ/mole) for ice using the
following lab data:
(HINT: Think about the heating curves for H20)
Mass of empty calorimeter + stir bar: 255.060 g
Mass of calorimeter, stir bar, and warm water: 309.602 g
Mass of calorimeter, stir bar, water, and melted ice:
312.170g
Mass of warm water in calorimeter: 54.543 g
Mass of ice added: 2.568 g
The initial temperature of water: 35.3 C
The final temperature of water/melted ice: 31.1 C
Specific heat of water: 4.184 J
Hfusion of water: -285
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A 52 cm long thin string is attached to a 25 g mass. You bring the mass up until you make a 4.2◦ angle with respect to the equilibrium position and let go. You start the timer when the simple pendula has a 2.1◦ angle with respect to the equilibrium position. (a) What are the equations for the position, velocity, and acceleration of the system? (b) Using your equations, determine what the three will equal at the instant you let go, and 3.0 s after you let go. Assume no damping occurs.
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What is the reason for the seasons? Explain fully why different hemispheres experience opposite temperatures at some times of the year and similar temperatures at others. Identify the months when these events occur.
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An n-type silicon wafer undergoes a pre-deposition diffusion process with a constant surface concentration of boride gas; the resulting concentration of boron in silicon at the surface is estimated to be 1x1018 atoms cm-3. The background concentration of trace boron atoms in the silicon wafer is estimated to be 1x1014 cm-3. (A) Estimate the depth of the p-n junction below the surface when the background doping concentration of the n-type impurity is 3.45 x1016 cm-3; assume the diffusion process proceeds for 10 minutes and has a diffusion parameter given by 10-12 cm2 s -1. (B) Estimate the number of boron atoms (per cm^2) introduced in this thin surface layer following the pre-deposition step.
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1. Choose the scenario under which each of the following Doppler shift effects will be seen:
choices are:
The source and observer are approaching one another
The source and observer are moving away from one another
The source and observer are stationary relative to one another
1.1 Light is shifted towards the blue end of the spectrum (blue-shifted).
1.2 The apparent pitch of the source is lower than the actual pitch of the source.
1.3 There is no apparent change in the pitch or color.
1.4 Light is shifted towards the red end of the spectrum (red-shifted).
1.5The apparent pitch of the source is higher than the actual pitch of the source.
2.Sounds coming from moving objects, such as the siren of an emergency vehicle, appear to change pitch as the object moves toward or away from you. Compare the frequency of a siren based on its motion toward or away from you.
rate from highest to lowest
away from you 31 miles per hour
toward you at 34 miles per hour
away from you at 34 miles per hour
toward you at 55 miles per hour
neither toward nor away from you
toward you at 3 miles per hour
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A car with inertia 1500kg is driving down a one-way street at 15 m. An unobservant s
driver of a 2000kg pickup truck is driving the wrong way down the street at −10 ms , and runs head on into the car. (Assuming the system consists of the car and the truck only)
a) What is the velocity of the car after the collision if the velocity of the truck is 5 ms ?
b) What is the coefficient of restitution for this collision? What type of collision is this?
c) What is the velocity of center of mass of the system?
d) Find the center-of-mass kinetic energy for the system.
e) What is convertible kinetic energy of the system before the collision?
f) What is the minimum amount of energy required to conserve the momentum of the system?
g) What is the total kinetic energy of the system before the collision?
h) What is the total kinetic energy of the system after the collision?
i) What is the change in kinetic energy of the system due to this collision? Since energy cannot be destroyed, explain what happens to this energy.
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5. A giant lollipopconsists of a 280gram 14cm diameter disk on the end of a 40 gram 25cm long stick. A child is balancing a GIANT lollipop on the end of her finger.
a. What is the moment of inertiaof the lollipop about the end balanced on the childs finger?
b. If the child holds the lollipop from the end of the stick at and angle of 30o abovethe horizontal, what are the forcesthey must exert on the stickto keep it in equilibrium?
c. If the childlets loose her grip so that the lollipop begins to rotatein her handfrom the 30o position, what is the instantaneous angular acceleration of the lollipop?
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