Classical Mechanics

Thursday, February 02, 2006

Problem Set (engineering mechanics)

Prob.1 The 3500-lb automobile is traveling down the 10degree inclined road at a speed of 20ft/s. If the driver wishes to stop the car, determine how far his tires skid on the road if he jams on the brakes causing his wheels to lock. The coefficient of kinetic friction between the wheels and the road is uA= 0.5.

Prob2. The bus B has a weight of 15,000 lb and is traveling to the right at 5ft/s. Meanwhile a 3,000 lb car A is traveling at 4ft/s to the left. If the vehicles crash head-on and become entagled, determine their common velocity just after the collision. Assume that the brakes are not applied during collision.

Prob3. The 400-kg mine car is hoisted up the incline using the cable and motor M. For a short time, the force in the cable is F=(3200tsquare)N, where t is in seconds. If the car has an initial velocity V1=2m/s when t=0, determine its velocity when t= 2s.

Prob4. A 2-lb pendulum bob is released at theta=0 degree with a velocity Vo. When it reaches the lower position theta=90 degrees, a 0.1 lb bullet strikes the bob from below with a velocity of 1600 ft/s and becomes embedded in the bob in 0.2 after the initial contact. Determine the minimum velocity Vo fo the bob so that when the impact occurs the cord OC does not become slack. Assume the bullet creates a constant force on the bob during the impact.

Prob5. The 150 lb fireman is holding a hise which has a nozzle diameter of 1 in.a and hose diameter of 2in. If the velocity of the water at discharge is 60ft/s, determine the resultant normal and frictional force acting on the amn's feet at the ground. Neglecy the weight of the hose and the water within it. Gamma weight = 62.4 lb/ft cube.

Prob6. A golf ball struck on earth rises to a maximum height of 20ft & hits the ground 250 yards away. How far will the same golf ball travel on the moon if the magnitude & the direction of its velocity are the same as they were on earth immediately after the ball was hit? Assume that the ball is hit and lands at the same elevation in both cases and that the effect of the atmosphere on earth is neglected so that the trajectory in both cases is a parabola. The acceleration of gravity on the moon is 0.165 times that on earth.

Prob7. A baseball player catching a ball can soften the impact by pulling his hand back. Assuming that a 5-oz ball reaches his gloce at 90mi/h and that the player pull his hand back during the impact at an average speed of 30ft/s, over a distance of 6 inches,, bringing the ball to a stop, determine the average impulsive force exerted on the player's hand.

Prob8. Just for fun, two 750-N engineering students A and B intend to jump off the bridge from rest using an elastic cord (bungee cord) having a stiffness k= 1300 N/m. They wish to just reach the surface of the river, when A, attached to the cord, lets go of B at the instant they touch the water. Determine the proper unstretched length of the cord to the stunt, and calculate the maximum acceleration of student A and the maximum height he reaches, comment on the feasibility of doing the stunt.

Prob9. The tenns ball is struck with a horizontal velocity Vo that strikes the ground at B, and bounces upward at angle=30 degrees. Det. the initial velocity Vo, the final velocity Vb, and the coefficient of restitution between the ball and the ground.

Friday, December 23, 2005

Graduate studies requirements

* this list is taken from Purdue University requirements for Graduate Studies in Physics

Classical Mechanics
1. Fowles and Cassiday, Analytical Mechanics
2. Marion and Thornton, Classical Dynamics of Particles and Systems
3. (my list) Barger and Olsson, Classical Mechanics: A Modern Perspective
4. (my list) Symon, Mechanics

Electromagnetic Theory
1. Griffiths, Introduction to Electrodynamics
2. Reitz, Milford, and Christy, Foundations of Electromagnetic Theory
3. Marion and Heald, Classical Electromagnetic Radiation

Quantum Physics
1. French and Taylor, An Introduction to Quantum Physics
2. Eisberg and Resnick, Quantum Physics of Atoms, Molecules, Solids, Nuclei, and Particles

Thermal Physics
1. Kittel and Kroemer, Thermal Physics
2. (my list) Reif, Fundamentals of Statistical and Thermal Physics

General Modern Physics
1. Weidner and Sells, Elementary Modern Physics
2. Krane, Modern Physics
3. Sandin, Essentials of Modern Physics
4. Serway and Moses, Modern Physics
5. Tipler and Llewellyn, Modern Physics
6. (my list) Beiser, Concepts of Modern Physics

Wednesday, December 21, 2005

Important Equations in Classical Mechanics

1. Newton's second law of motion
2. Lagrange's equations
3. Hamilton's equations
4. Force and potential energy
5. Conservation of energy
6. Hooke's law
7. Equation of simple harmonic motion
8.

Thursday, December 15, 2005

Topics

* Based on Marion and Thornton's Classical Dynamics of Particles and Systems, 4th edition

Part 1
1. Matrices, Vectors, and Vector Calculus
2. Newtonian Mechanics—Single Particle
3. Oscillations
4. Nonlinear Oscillations and Chaos (optional)
5. Gravitation

Part 2
1. Review of Part 1*
2. Some Methods in the Calculus of Variations
3. Hamilton’s Principle—Lagrangian and Hamiltonian Dynamics
4. Central-Force Motion
5. Dynamics of a System of Particles
6. Motion in a Noninertial Reference Frame
7. Dynamics of Rigid Bodies
8. Coupled Oscillations**
9. Continuous Systems; Waves**

For PUP students, click here.

Wikipedia article on Classical Mechanics

In physics, classical mechanics or Newtonian mechanics is one of the two major sub-fields of study in the science of mechanics, which is concerned with the set of physical laws governing and mathematically describing the motions of bodies and aggregates of bodies. The other sub-field is quantum mechanics. Roughly speaking, classical mechanics was developed in the 400 years since the groundbreaking works of Brahe, Kepler, and Galileo, while quantum mechanics developed within the last 100 years, starting with similarly decisive discoveries by Planck, Einstein, and Bohr.

Click here to read more...

Sunday, July 03, 2005

About clasmech

Clasmech is short for Classical Mechanics - the oldest branch of physics. Obviously, this web site shall host information related to the study of classical mechanics. Research papers may also be posted here. Thanks for dropping by.