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Energy

An electron with a speed 5.00x10^8 cm/s enters an electric field of magnitude 1.00x10^3 N/C, traveling along a field line in the direction that retards its motion. (a) how far will the electron travel in the field before stopping momentarily, and (b) how much time will have elapsed? (c) If the region containing the electric field is .08m long, what fraction of the electron's initial kinetic energy will be lost in that region?

An electron with a speed 5.00x10^8 cm/s enters an electric field of magnitude 1.00x10^3 N/C, traveling along a field line in the direction that retards its motion. (a) how far will the electron travel in the field before stopping momentarily, and (b) how much time will have elapsed? (c) If the region containing the electric fiel

Potential and Kinetic energy of an oscillator

A block of mass m = 0.65 kg is fastened to a spring with k = 65 N/m. The block is pulled a distance x = 11 cm from its equilibrium position at x = 0 on a frictionless surface and released from rest at t = 0. v= 1.1 m/s^2 Calculate the potential and kinetic energy of the oscillator when the block is at x = 0.

Find the kinetic energy

Find the kinetic energy of a cylindrical shaft of mass 2.0 kg and radius 10cm rotating about its central axis at 600 rad/s a. 1800 j b. 1200 j c. 18000 j d. 12000 j

Energy and Momentum: Spring Goes Around Track

The 0.31 kg mass slides on a frictionless wire that lies in the vertical plane. The ideal spring attached to the mass has an equilibrium length of 80 mm and its spring constant is 120 N/m. The mass is released at point A, from rest. Calculate the minimum distance b, if the mass is to slide all the way around the loop to poin

Energy and Momentum: Rebounding Ball

A 0.075 kg ball hits a frictionless, rigid, horizontal surface with a speed of 1.2 m/s at the angle q1 = 70 deg. The angle of rebound is q2 = 62 deg. Compute: a) the speed of the ball immediately after rebound. b) the resultant impulse acting on the ball during its time of contact with the surface. See attachment for

Energy and Momentum: Orbiting Spacecraft

A spacecraft is traveling in a circular orbit (see attached file) around the earth at an altitude of 210 miles. When the craft reaches point A, its engines are fired for a short period, reducing its speed by 7.5%. The resulting path is the (elliptical) crash trajectory AB. Determine the angle b, measured from the nonrotating x

Ball Rolling up an Incline

A 10.0 kg bowling ball of radius 15 cm rolls without slipping along a horizontal surface with a speed of 4.0 m/s as it approaches an incline. What is the total kinetic energy of the ball as it rolls along the horizontal? How high above the floor level will the ball reach (with no slipping) as it rolls up the incline?

One dimension collisions

A ball of mass 1.5kg is thrown upward. it leaves the thrower's hand with a velocity of 10 m/s. Assuming the upward direction is positive: a. how long does it take for the ball to return to the throwers hand b.what is the ball's final velocity just before it reaches the hand? c. what is the change in momentum of the ball?

Propulsive Efficiency

Propulsive efficiency can be defined as the useful power output over the rate of change in energy of the airflow through the engine. If useful power is thrust x velocity, and the rate of change of KE is expressed in terms of air mass flow rate, provide an expression for ηP in these terms. If the efflux pressure is brought

Derive Expression Where Needed

1. A motorcyclist is coasting with the engine off at a steady speed 17 m/s but enters a sandy stretch where the coefficient of friction is .80. Will the cyclist emerge from the sandy stretch without having to start the engine if the sand lasts for 15 m. If so, what will be the speed upon emerging? 2. One car has twice the

Work and Energy

Is Work done = average force * displacement= 1/2 kx^2 = 1/2*31*0.02^2 or 1/2*31*0.02?

Weather Forecasts

Question: It is the middle of winter and the weatherman forecasts a cold, overcast, but dry day, with an average temperatures of -2 degrees Celsius. However, he highlights the presence of a strong wind with a wind chill factor that will make it feel like -10 degrees Celsius. What is meant by the term 'wind chill'? How can it be

Elastic and Inelastic Collisions

A 10 gram bullet is fired horizontally into, and becomes embedded in, a suspended block of wood whose mass is 0.890 kg. (a) How does the speed of the block with the embedded bullet immediately after the collision compare with the initial speed of the bullet? (b) If the block with the embedded bullet swings upward and its center

Yet more simple physics

Think about a rollercoaster. If it loaded at a height of about 500m and then dropped down to almost ground level and was followed by 7 circles where the circles height was about the same it would not work well. Explain in terms of kinetic energy, potential energy, etc. why not. (Picture included if needed.)

Thermodynamics

An ideal gas mixture consists of 3 kg of Ar and 6 kg of CO2 gases. The mixture is now heated at constant volume from 250 K to 350 K. The amount of heat transfer is:

Molecules in vacuum

In an ultra-high vacuum system, the pressure is measured to be 1.00 * 10^-10 torr, the average molecular diameter is 1.00 * 10^-10 m, the average molecular speed is 500 m/s and the temperature is 300 K. Find the number of molecules in a volume of 1.00 m^3 and the mean free path of the molecules.

Mixed Energy Photon Beam

A collimated gamma ray beam consists of equal numbers of 0.1 MeV and 1.0 MeV photons. If the beam enters a 15 cm thick concrete shield, what is the relative portion of 1 MeV photons to 0.1 MeV photons in the emergent beam?

Finding the lagrangian of a system

A triangular piece of wood is free to slide, without friction, in one dimension along a table, forming a moving inclined plane. A block of wood, placed on this inclined plane only moves as the result of the triangular block moving. There is no friction between the triangular piece of wood and the block. Find the lagrangian fo

Electrical Potential Energy

A 100-µF parallel-plate capacitor is charged to 500 V. It is then disconnected from the charging source and insulated. (a) How much energy is stored on the capacitor? (b) If the plates are pulled apart to a separation that is twice their initial separation, what energy is stored on the capacitor? (c) If the answers are not i

Harmonic Oscillator and Wave Packets

Consider the 1-D harmonic oscillator, with Hamiltonian H=p²/2m+½mw²x²=hw(a¬a+1/2), and with energy eigenstates H|n}=En|n}=hw(n+1/2)|n}. The eigenvectors of the annihilation operator a are known as coherent states: a|z}=z|z}, where z is in general a complex number (a is not Hermitian, so z is not necessarily real). Take |z}

Planck's function

Using planck's energy density per unit frequency formula. r(x)= x^3 / e^x -1. Plot r(x) from excel spread sheet and determine its maximum. I need help in using excel to graph this inorder to find the maximum. Then based on the maximum I am supposed to determin planck's constant

Height and Speed on Trapeze

A circus perfomer swings down on a trapeze from a height of 18m (starting from base ground). He picks up an assistant standing on the floor, and just reaches a platform of height h, depositing the assistant on the platform as they reach zero speed together. The performer's mass is 100kg and his assistant's mass is 50kg. The le

Displacement of a Mass on a Spring

a) When the displacement of a mass on a spring is 1/2*A the half of the amplitude, what fraction of the energy is kinetic energy? Express your answer as a percent. b) At what displacement, as a fraction of A, is the energy half kinetic and half potential?

temperature and phase changes in making iced tea

See attached file. Calorimetry involving temperature and phase changes in making iced tea. PSS 17.2: Making the Iced Tea Learning Goal: To practice Problem-Solving Strategy 17.2 for calorimetry problems involving temperature and phase changes. On a hot summer day, you decide to make some iced tea. First, you brew a volum

Physics Problems (Angular Distance; Angular Speed; Tangential Speed etc.)

I would like for you to show me all of your work/calculations and the correct answer to each problem. 11. A jogger on a circular track that has a radius of 0.250 km runs a distance of 1.00 km. What angular distance does the jogger cover in (a) radians and (b) degrees? 15. In Europe, a large circular walking track with a di

Compressive force on rod

The ball has a weight of 15 lb and is fixed to a rod having a negligible mass. If it is released from rest when theta = 0 deg., determine the angle theta at which the compressive force in the rod becomes zero (see attachment for an illustration) answer should be 48.2 deg. Not sure how to get there though.

Force of a Compressed Spring

The collar has a weight of 8lb. If it is released from rest at a height of h= 2ft from the top of the uncompressed spring, determine the speed of the collar after it falls and compresses the spring 0.3ft.

Potential energy

The Great Sandini is a circus performer with mass 60.0 kg who is shot from a cannon (actually a spring gun). You don't find many men of his caliber, so you help him design a new gun. This new gun has a very large spring with a very small mass and a force constant of 1300 N/m that he will compress with a force of 5000 N. The insi

Applying the Conservation Laws

A 2.5 kg block collides with a horizontal spring of negligible mass and spring constant. k=320 N/m. The block compress the spring by 8.5 cm from its rest position. How fast was the block going when it hit the spring if the frictional coefficient between the block and the horizontal surface is 0.40?