Questions
what percentage by volume of a water polo ball lies under the waterline as it floats...

what percentage by volume of a water polo ball lies under the waterline as it floats in still water?

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An unstable nucleus of mass 1.7 ✕ 10−26 kg, initially at rest at the origin of...

An unstable nucleus of mass 1.7 ✕ 10−26 kg, initially at rest at the origin of a coordinate system, disintegrates into three particles. One particle, having a mass of

m1 = 1.8 ✕ 10−27 kg,

moves in the positive y-direction with speed

v1 = 5.4 ✕ 106 m/s.

Another particle, of mass

m2 = 8.0 ✕ 10−27 kg,

moves in the positive x-direction with speed

v2 = 3.2 ✕ 106 m/s.

Find the magnitude and direction of the velocity of the third particle. (Assume that the +x-axis is to the right and the +y-axis is up along the page.)

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An emf is induced in a conducting loop of wire 1.20 m long as its shape...

An emf is induced in a conducting loop of wire 1.20 m long as its shape is changed from square to circular.
Find the average magnitude of the induced emf if the change in shape occurs in 0.155 s and the local 0.478-T magnetic field is perpendicular to the plane of the loop.

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Problem Statement Charges -2nC and 2nC are located at x= -0.1cm and x=0.1cm respectively. Determine the...

Problem Statement

Charges -2nC and 2nC are located at x= -0.1cm and x=0.1cm respectively. Determine the electric field at the points (-1 cm, 0 cm), (1 cm, 0 cm), (0 cm, 1cm), (0 cm, -1 cm) and (1 cm, 1 cm).

Visual Representation

  • Draw a sketch of the charge distribution.

  • Establish a coordinate system and show the locations of the charges.

  • Identify the point P at which you want to calculate the electric field.

  • Draw the electric field of each charge at point P. ⃗

  • Use symmetry to determine if any components of Enet are zero.

Mathematical Representation ⃗

  • For each charge, determine its distance from P and the angle of E i

  • Determine the field strength of each charge.

  • Write each vector in component form. ⃗

  • Sum the vector components to determine E net.

  • Check result for correct units and that it is reasonable.

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A guy was dumped by his girlfriend and wants to jump off from a building 200...

A guy was dumped by his girlfriend and wants to jump off from a building 200 ft high. What is the required velocity he must start in order to touch down on her new boyfriend who stands on the ground, 30ft from the building. a) if he jumped out horizontally b)the guy jumped down with a depression angle of 30 degrees. Find the impact velocity and speed. Does he have any chance?

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1. at some fancier sledding hills there is a motorized rope loop used to pull sledders...

1. at some fancier sledding hills there is a motorized rope loop used to pull sledders back to the top of the hill. the hillside is inclided at 25 degrrees and the rope pulls sledders at a constant 2.5 m/s. sleds arent quite a frictionless a good skis, so let's say that thete is a coefficient of kinetic friction of =0.05 between the sled and the snow.

a) how much power must the drive motor provide to pull a single sledder and sled with a combined mass of 180 kg up the hill under these conditions

b) if the sled run is 40m long, how much work does the motor do on the sledder and sled during the trip back to the top of the hill?

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My question is would this lab procedure be a valid method of calculating the coefficient of...

My question is would this lab procedure be a valid method of calculating the coefficient of static friction when you are only allowed to make measurements of distance and not of mass. What steps should I add or change?

Lab Objective: Find the coefficient of static friction between a CPO sled and a smart track by only measuring the distance.

1. Angle the straight track so that it acts as a ramp

2. Draw the freebody diagram of the sled on the straight track showing a normal force perpendicular to the ramp surface

3. Break the horizontal and vertical forces into their x and y components and sum them together. Make sure to break the force of gravity apart into its x and y components, applying Newtons’s 2nd law equations to establish relationships between gravity, Fn, and static friction. The x and y components of gravity are the normal force as its y component, Fg (y) = Fn = mgcosθ and F g (x) = mgsinθ as the x component.

4. Measure the horizontal and vertical distances of the ramp by using a meterstick.

5. Calculate the angle at the horizontal (angle of incline) by using inverse tan(height of ramp /base length).

6. Calculate the tangent of the angle of incline using the equation of tanθ=sin θ/cos(θ). The coefficient of static friction is tangent to the angle at which the sled slides.

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what is the equation of motion that governs sound production in a simple coil speaker? i...

what is the equation of motion that governs sound production in a simple coil speaker?

i know that there is an electromagnetic force that is created by the current which interacts woth the magnetic field of the permanent magnet... but what spcecificay governs the motion of electrical energy being converted into the mechanical energy that produces the sound waves?

furthermore, how is this electromagnetic force produced by the current? and how does this force relate to amperes and lorentz law?

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Problem 1 [6] Compute the eigenvalues of Hˆ = pˆ 2 2m + 1 2 mΩ...

Problem 1 [6] Compute the eigenvalues of Hˆ = pˆ 2 2m + 1 2 mΩ 2xˆ 2 + λxˆ using two different methods: 1. Complete the square in 1 2mΩ 2x 2+λx (that is, write the term as 1 2mΩ 2 (x− x0) 2+C with suitable constants x0 and C) and use the exact eigenvalues En = (n+ 1 2 )¯hω of a harmonic oscillator with potential V (x) = 1 2mω2x 2 . 2. Apply second-order perturbation theory in λ

Problem 2 [2] Compute the eigenvalues of the matrix Hˆ = 2 λ λ 3 − 2λ ! and Taylor expand them to second order in the real number λ

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In winter, people play hockey on Alta Lake in Whistler. However, it is not considered safe...

In winter, people play hockey on Alta Lake in Whistler. However, it is not considered safe by the Canadian Red Cross to play hockey on ice until the ice is 20 cm thick. On a winter day with a temperature −10◦C, it is observed that the lake has a 1cm thick layer of ice over the entire surface.
Constants which may be of use: The thermal conductivity of ice is 2.18W/m · K. Density of ice 916.7 kg/m3 and water 1000 kg/m3. Latent heat of fusion 334x103 J/kg.

a) If the air temperature remains at −10◦C, find the rate in cm per hour at which ice is added to the layer initially. The thermal conductivity of ice is 2.18W/m · K. Answer in cm/hour. The units are already written for you.

b) Find the rate in cm per hour at which ice is added to the layer as a function of the thickness X, where X is the number of centimeters.

c) Estimate the time it takes before you can safely play hockey

Answers: a) 2.56 cm/hr b) 2.56/X c) 3 days

SHOW ALL WORK

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A gas is compressed at a constant pressure of 0.800 atm from 9.00 L to 2.00...

A gas is compressed at a constant pressure of 0.800 atm from 9.00 L to 2.00 L. In the process, 350 J of energy leaves the gas by heat.

(a) What is the work done on the gas?
J

(b) What is the change in its internal energy?
J

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a) if energy is not a vector, what is the diffwrneve between a "+" work and...

a) if energy is not a vector, what is the diffwrneve between a "+" work and a "-" work?

b) Give an example of a system in which the total energy is constant, yet energy is transferred by work

c) An onjevg slides across a surface. there is friction betwren the objecy and the surface. explain why the work done by friction misg be included on the right side of the equations delta E = W even if borh the objecg and the surface are included in the system used to analyze the situation.

d) do you supoise that the force between two magnegs would be conservative? Explain your reasoning

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a.) show that a simple pendulum has a stable equilibrium point at theta=0. b.) Find the...

a.) show that a simple pendulum has a stable equilibrium point at theta=0.

b.) Find the natural frequency w of the system. (show work)

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A4μCchargeisplacedatthepoint⃗r1 =2ˆicmandan-4μCchargeisplacedat ⃗r2 = −2 ˆi cm. The charges do not move. a. What is the...

A4μCchargeisplacedatthepoint⃗r1 =2ˆicmandan-4μCchargeisplacedat ⃗r2 = −2 ˆi cm. The charges do not move. a. What is the electric field (magnitude and direction) at the origin? b. What is the electric field (magnitude and direction) at the point (0,2)? c. What is the electric field at the point (4,4)? For this part give your answer in both unit vector (ˆi, ˆj) notation and in magnitude and direction relative to ˆi.

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The bright yellow sodium line in the sodium spectrum is actually a pair of closely spaced...

The bright yellow sodium line in the sodium spectrum is actually a pair of closely spaced lines at 589.0 nm and 589.6 nm. You observe the sodium spectrum using a diffraction grating with a spacing of 1700 nm . Find the angular separation between the two sodium lines in first order. Find the angular separation between the two sodium lines in second order. Express your answer to two significant figures and include the appropriate units.

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