Share
Explore BrainMass

Energy

Energy is an indirectly observed quantity which comes in many forms. There are many forms of energy such as, kinetic energy, potential energy, radiant energy and many more. Energy is an indispensable prerequisite for performing mechanical work and the concept has great important in natural science.

Energy as a concept emerged out of the idea of living force, which was defined as the product if the mass of an object and its velocity squared. It is believed that the living force is conserved.

The law of conservation of energy was first postulated in the 19th century. It was applied to isolated systems. Noether’s theorem states the conservation of energy is a consequence of the fact that the laws of physics do not change over time.

Energy can be used in different contexts in which energy is used. In chemistry, energy is used to describe heat being released from chemical reactions. In biology, energy is responsible for growth and development of organisms. In earth sciences, energy describes the movement of tectonic plates. Humans input energy to sustain life through calories via food.

Energy density is a term used to denote the amount of useful energy stored in a given system or region of space per unit volume. For example, nuclear reactions have a much higher energy density than coal combustion reactions.

Harmonic vibration of a mass

A mass of 0.3 kg is suspended from a spring of stiffness 200 N m-1. If the mass is displaced by 10 mm from its equilibrium position and released, for the resulting vibration, calculate: (a) (i) the frequency of vibration. (ii) the maximum velocity of the mass during the vibration. (iii) the maximum acceleration of the

System of springs: Energy stored in different springs

You can assume that air resistance and other frictional forces can be ignored in this question See attachment a) Define a datum for the gravitational potential energy of particle P. b) Write down the gravitational potential energy of particle P at a general point of motion. c) Write down the kinetic energy of a particl

Understanding Pseudo Force

What is a pseudo force? Explain with the help of an appropriate example. Solve the following problem using the concept of pseudo force: Two rectangular blocks are stacked one over the other on a table. The lower and upper blocks have masses of 25 kg and 5 kg respectively. The coefficient of kinetic friction between the

A half harmonic oscillator

Consider the corresponding problem for a particle confined to the right-hand half of a harmonic-oscillator potential: V(x) = infinity, x< 0 V(x) = (1/2)Cx^2, x >= 0 a. Compute the allowed wave function for stationary states of this system with those for a normal harmonic oscillator having the

Prolate nuclear core and rotational bands

1. Consider a deformed prolate nuclear core consisting of an even number of neutrons and one even number of protons outside of this core is a neutron in a d5/2 state a. What would the degeneracy of the state be if the deformation were zero? b. What would be in the single particle shell model for deformed nuclei

Internal enrgy and entropy of a Van der waals gas

7.4 Consider n moles of a Van der Waals gas. Show that (dU/dV)_T = n^2a/V^2. Hence show that the internal energy is U = the integral from zero to T of C_vdT - an^2/V + U0 where U0 is a constant. {Hint: Express U = U(T,V)}. 7.5 As in the previous question, consider n moles of Van der Waals gas. Show that (a) S = the in

hydrogen with a nucleus of finite mass

The spectrum of hydrogen with a nucleus of finite mass. The analysis in Section I-7 of the text assumes that the nucleus remains fixed as the electron orbits about it. This corresponds to assuming that the proton mass is effectively infinite. More correctly. we should picture the proton and electron as orbiting about their co

Finding the Potential Energy and Magnitude of Force

1. If a certain spring stretches 8.93072 cm when a load of 18.6372 N is suspended from it, how much will the spring stretch if it is cut in half and when 30.2799 N is suspended from it? Answer in units of cm 2.A certain spring stretches 4.5 cm when it supports a mass of 0.77 kg. If the elastic limit is not reached, how far w

A proton in a well

The figure [attached] shows electric potential V along an x axis. A proton is to be released at x = 3.5 cm with initial kinetic energy 3.5 eV. The scale of the vertical axis is set by Vs = 10.0 V. (a) If it is initially moving in the negative direction, it either reaches a turning point (if so, what is the x coordinate of th

Photon and Radio Waves

A radio station broadcasts at a frequency of 1MHz with a total radiated power of 5000 watts. (a) What is the wavelength of this radiation? (b) What is the energy (in electron-volts) of the individual quanta that compose the radiation? How many photons are emitted per second? per cycle of oscillation? (c) A certain radio rec

Activity for simulating the periodic table

Imagine that you want to create an activity for a group of children to simulate the periodic table. Suggest items that you may use and how they may be organized in rows and columns. If you have some ideas I'd like to learn from you and also if you know books or internet sites let me know so I can read and understand more.

Machlett Dynamax X-Ray Tube

Please provide assistance for the following problems. step by step calculations are given. Question: 1. Consider an Machlett Dynamax x-ray tube with a tungsten target operating with an accelerating potential of 100 kV and filament current of 4.4A. The anode target angle is 17 degrees and the apparent focal spot is 1 mm by 1

The angular speed of a wheel increases at a constant rate of 1.5 rad/s^2

Please see attachments for details. 11. The angular speed of a wheel increases at a constant rate of 1.5 rad/s2. During a certain 3.2 s time interval, it makes four complete revolutions. If the wheel started from rest, how long has it been in motion at the start of this time interval? 12. An airplane makes a circular turn

Gravitational Forces among the Four Objects

1.Three solid spheres of lead, each of mass 9.8 kg, are located at three corners of a square with side lengths of 50 cm. A small object is released at the forth corner. Considering only the gravitational forces among the four objects, determine the magnitude and direction of the acceleration of the smaller object when it is rele

Friction and Temperature Change Problem

A crate of fruit with a mass of 35.0 kg and a specific heat capacity of 3800 J/kg.K slides 8.30m down a ramp inclined at an angle of 40.0 degrees below the horizontal (acceleration due to gravity is 9.81m/s^2). If the crate was at rest at the top of the incline and has a speed of 2.40m/s at the bottom, the work (W_f) done

Internal energy of the gas system of a cylinder divided

Please refer attached file for Proper format of symbols. A cylinder is close at both ends and has insulating walls. It is divided into two compartments by a perfectly insulating partition that is perpendicular to the axis of the cylinder. Each compartment contains 1.00 mol of oxygen, which behaves as an ideal gas with ?=7/5.

Internal Energy of a Gas System: Partition, Conservation

I try to simplify my problem here. This is the place where I may have some misunderstanding in the adiabatic process. Consider a uniform cylinder with insulated wall cylinder that has a very thin and mass less partition at middle divide it into two sections. The left section contains gas molecules and the right side is attached

Nucleus of helium breaks up from rest into a nucleus

A nucleus of helium with mass 5 amu breaks up from rest into a nucleus of ordinary helium (mass = 4 amu) plus a neutron (mass = 1 amu). The energy liberated in the break-up is 0.89 MeV, which is shared (not equally) by the products in the form of kinetic energy. a) Using the conservation of momentum find the kinetic energy of

Tunneling Time and Probability of an Electron in a Square Well

Imagine an electron trapped in a well that has walls that are 5nm thick and 10eV high and is 10nm wide. calculate the probability of tunneling for an electron with 0.5eV of kinetic energy. Now, determine the number of times the electron would hit a wall each second. using these two pieces of information determine how long it wou

Quantum Mechanics (nanowire problem)

Given a Nanowire with cross sectional dimensions of 10 nm x 10 nm, what momentum would an electron in the ground state need in order to possess the same energy as a stationary electron (zero momentum) in the n=1,2 state? I need step-by-step solution please.

Acceleration of blood in vasculature; elevator springs energy

See attached file for the diagram. 1. The diagram shows the acceleration of blood in the vasculature versus time in seconds. Give the time at which the blood is moving with the maximum velocity. Explain your answer. 2. All modern elevators feature safety mechanisms. For example, if an elevator cable breaks, the falling el

Rotational Motion Diagram

Please refer to the attachment for questions complete with diagrams. 1. The spool has a weight of 400 lb and a radius of gyration of kG = 1.6 ft. A horizontal force of P = 12 lb is applied to the cable wrapped around its inner core. If the spool is originally at rest, determine its angular velocity after the spool has turned

Refraction of Material, DC Motor Current, Defibrillator & Speed

1. A light ray in material 1 goes into material 2. The angle of incidence in material 1 is 40.0o and the angle of refraction in material 2 is 31.0o. If the index of refraction of material 1 is 1.60, what is the index of refraction of material 2? 2. A dc motor has coils with a resistance of 16 and is connected to an emf of 12

Transitions in the hydrogen atom; emission lines, absorption spectrum

Please show all work. 1. For each of the following transitions in he hydrogen atom, calculate the energy, frequency, and wavelength of the associated radiation, and determine whether the radiation is emitted or absorbed. a. n=5 to n=1 b. n=4 to n=6 2. One of the emission lines of the hydrogen atom spectrum has a wave

How electrons move in conductors; how diodes and simple transistors work

Review the four required sources listed under Background Information above. Google the relevant topics if you need additional explanations. Based on these articles (and any additional material that you read from the Background Materials or other sources), write a paper explaining: 1. How electrons move in conductors,

Physics: Energy Problems

** Please see the attached file for the complete problem description ** Please provide me step by step solution. Problem 6: A mass (M=3kg) is placed in front of a spring with k=1200N/m, compressed d=40cm. The spring is released, shooting the mass forward from A to B (frictionless). The mass then travels along a flat surface

Questions about the Bose Electromagnetic machine

(2.1) The Bose electromagnetic fatigue testing machine in room 114 Upson-I applies load and displacements to a test specimen via the application of a variable magnetic field to permanent magnets aligned along the top load shaft. A simplified model of the internal structure is shown in the attachment. The specimen is held by the