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# Classical Mechanics

### Density and pressure

Find the magnitude of the resultant force on one side of the plate (See attached for full question)

### Physics: 3 Boxes Free Body Diagram

Problem: 3 boxes side by side on a table. (regular size box, larger box, regular size box). The boxes are given a small steady push. Please draw a free body diagram for each box. I am confused as to the paralell friction. Also, why would the boxes not move at all if the push was too small?

### Physics question: projectile motion

A soccer player kicks a ball at an intial speed of 11.0 m/s at an angle of 40.0 degrees to the ground. a) How far will the ball travel horizontally? b) How long is it in the air?

### Springs

Question: When an object weighing 50 N is hung from a vertical spring, it stretches 20 cm. Calculate the spring's elastic constant. If the 50 N load were replaced with a 80 N weight, how far would the spring stretch?

### Falling Objects

A first stone is dropped from the roof of a building. 2.50 s after that, a second stone is thrown straight down with an initial speed of 30.0 m/s, and it is observed that the two stones land at the same time. (a) How long did it take the first stone to reach the ground? (b) How high is the building? (c) What are the spe

### Kinematics: Two Locomotives

Two locomotives approach each other on parallel tracks. Each has a speed of v = 80 km/h with respect to the ground. If they are initially d = 9.0 km apart, how long will it be before they reach each other?

### Kinematics in One Dimension

An automobile traveling v = 85 km/h overtakes a L = 1.15 km long train traveling in the same direction on a track parallel to the road. If the train's speed is 80 km/h, how long does it take the car to pass it (min), and how far will the car have traveled in this time? (km) What are the results if the car and train are travel

### Kinematics: Motion Down and Incline

Do 12a and b. Well tell me how you figure out what vo is and the rest of the variables, the physics part, how you set the problem up, and do all the math and solve with an answer. Thanks.

### Kinematics: A Rock Thrown Downwards

A rock is thrown straight downward with an initial speed of 3m/s into a well. As the same time, the bucket 110 meters down at the bottom of the well is raised at a speed of 2m/s. Determine how far the rock has fallen when it hits the bucket. (Use g = 10 m/s^2).

### Pascal's Principle

The digging bucket on a large mechanical excavator is moved by a piston sliding within a single hydraulic cylinder. According to the manufacturer, the hydraulic fluid in the cylinder is pressurized to 1000 psi (6.895 x 10^6 Pa or 68 atm) by a pump. The cylinder has a diameter of 0.165 m and a stroke of 1.36 m. Determine the ma

### Critical stress, stress field

Question 3 Tensile tests of an elastic material show that it has a Young's modulus of... Please see attached past exam questions

### Poisson Ratio, Young's modulus

Please see attached past exam questions: (a) A material has a shear modulus of 4.615.... (b) Hence show that Young's modulus is...

### Mechanics and Young's Modulus

For the cross-section of the following figure, which is made from material with Young's modulus 100MN/m^2: (a) State the location of the centroid. (b) Show that the second moments of area about the z axis and teh axis aa are respectively 2.51x10^5 mm^4 and 1.26x10^6 mm^4. (c) A strut is made of this section. When subject to

### CT scanner image

A CT scanner has to be able to form an image within a 40cm diameter image area. The spatial sampling along each profile is 1mm. What angular resolution (the angle between projections) is required to match this sampling distance at the boundary of the image area?

### Basic Physics: Average Force; Kinetic, Potential and Mechanical Energy; Tangential Speed; Pendulum

38. In an emergency stop to avoid an accident, a shoulder-strap seat belt holds a 60-kg passenger firmly in place. If the car were initially traveling at 90 km/h and came to a stop in 5.5 s along a straight, level road, what was the average force applied to the passenger by the seatbelt? 66. A person standing on a bridge at a

### Tension on a bridge cable

A knight in armour on a horse leaves the castle. His squire has mistakenly lowered the drawbridge 20 degrees below the horizontal. The knight and his horse stop when their combined center of mass are 1 metre from the end of the bridge. The uniform bridge is 8 metres long and has a mass of 2000 kg. The lift cable is attached t

### Derive the magnetization and the susceptibility of a system of N non-interacting magnetic dipoles in the presense of an external magnetic field in the high temperature limit.

By evaluating the canonical partition function, derive the magnetization and the susceptibility of a system of N non-interacting magnetic dipoles in the presense of an external magnetic field in the high temperature limit.

### Damped Egg on a Spring

Please do not place your response in a .pdf or .cdx format, but Word documents are okay. Thanks! Here's the actual problem: A 50.0-g hard-boiled egg moves on the end of a spring with force constant k=25.0 N/m. It is released with an amplitude 0.300 m. A damping force F_x=-bv acts on the egg. After it oscillates for 5.00 s,

### Analyzing Simple Harmonic Motion

The applet at the following site (http://mp.pearsoncmg.com/probhtml/ActivePhysics/pt1a/Media/Vibrations/PositionGraphsEqns/Sim4.html) shows two masses on springs, each accompanied by a graph of its position versus time. A) What is an expression for x_1 (t), the position of mass I as a function of time? Assume that position i

### Hitting a Tennis Ball

The tennis ball has a horizontal speed of 15 m/s when struck by the racket. If it then travels away at an angle of 25 degrees from the horizontal and reaches a maximum altitude of 10m, measured from the height of the racket, determine the magnitude of the net impulse of the racket on the ball. The ball has a mass of 180g. Neglec

### Sidereal Time

Calculate local sidereal time for noon on December 4 in Green Bank West Virginia USA.

Show that in the case of zero external force the equation v=(fL/kT)^2 D/L (e^(fL/kT) - 1 - fL/kT)^-1 reduces to 2D/L. Then show that at high force (but still smaller than (epsilon/L)) the equation reduces to v=(fL/kT)^2 D/L (e^(-fL/kT)).

### Sliding Box Kinetic Friction Calculated

The 30-lb box A is released from rest and slides down along the smooth ramp and onto the surface of a cart. If the cart is fixed from moving, determine the distance s from the end of the cart to where the box stops. The coefficient of kinetic friction between the cart and the box is uk= 0.6. See the attachment.

### Speed of Bullet

A 5.00-g bullet is shot through a 1.00-kg wood block suspended on a string 2.000 m long. The center of mass of the block rises a distance of 0.45 cm.Find the speed of the bullet as it emerges from the block if its initial speed is 450 m/s.

### Maximum Angle of Incline

A spherical shell starts from rest and rolls down an incline. The coefficient of static friction between the shell and incline is (Us=.2). What is the maximum angle of incline such that the shell will roll without slippage?

### Sliding Plates

Each of the three plates has a mass of 10kg. If the coefficients of static and kinetic friction at each surface of contact are us = 0.3 and uk = 0.2 respectively, determine the acceleration of each plate when the three horizontal forces are applied. See attachment for diagram.

### Volume and density problem

A block of wood half as dense as water floats with half its volume above water. A piece of iron is then tied on top so the wood floats with only 1/4 its volume above surface. If the wood and iron are turned over so that the iron is submerged beneath the wood, then the volume of wood above the water surface will be? Why?