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Applied Physics

Horizontal Beam & Disk of Mass

7. A horizontal beam length= 10m, mass= 25kg that is pivoted at the wall, with its far end supported by a cable that makes an angle 50° with the horizontal. If a person with a mass of 60kg stands 3.0m from the pivot, what is the tension in the cable? I need to know all of the forces acting on the beam. 8. A disk of mass M and

Applied vector and pulley problems

(See attached file for full problem description) 11. Consider two objects whose position vectors are given by r1 and r2 and whose momenta are given by p1 = m1v1 and p2 = m2v2 respectively. Show that in the special case that the center of mass of the two bodies is at rest at the origin (that is P = p1 + p2 = 0, and the positi

Physics help

(See attached file for full problem description) 1. A constant-volume gas thermometer is calibrated in dry ice (-80.0°C ) and in boiling ethyl alcohol (78.0°C ). The respective pressures are 0.900 atm and 1.635 atm. (Note that we have the linear relationship P = A + BT, where A and B are constants.) (a) What value of ab

Water wave/Deep water waves

A water wave is called a deep-water wave if the water's depth is more than 1/4 of the wavelength. The speed of a deep water wave depends on its wavelength: v = sqrt((g.lambda)/2pi). Longer wavelengths travel faster. Let's apply to this to a standing wave. Consider a diving pool that is 5.0 m deep and 10.0 m wide. Standing w

Momentum and Impulse questions

Force of a Baseball Swing. A baseball has mass 0.145 kg. 1. If the velocity of a pitched ball has a magnitude of 45.0 m/s and the batted ball's velocity is 55.0 m/s in the opposite direction, find the magnitude of the change in momentum of the ball. 2. Find the magnitude of the impulse applied to it by the bat. 3. If t

Force and Angle

18. the leg and cast in picture (attached) weigh 220N (w1) Determine the weight w2 and the angle needed so that no force is exerted on the hip joint by the leg plus the cast. 41. The coefficient of static friction between a 3.00 kg crate and the 35.0 degree incline it sits on is 0.300. What minimum force (F) must be appl

Atwood Machine

Find the equation of motion for the Atwood machine depicted in the diagram.

Young's Modulus Problem

A steel wire of length 2.06 m with circular cross section must stretch no more than 0.290 cm when a tensile force of 350 N is applied to each end of the wire. 1. What minimum diameter d_min is required for the wire? Express your answer in millimeters. Take Young's modulus for steel to be Y = 2à?1011 Pa.

What is the hydraulic force needed to lift a car?

What force must be applied to a small cylinder piston with a diameter of 0.32 m to lift a car weighing 12,000N that is supported by the piston in a large cylinder that has a diameter of 1.4m? Assume that there is a closed chamber in the common between the two pistons and that the chamber is filled with hydraulic oil.

Rotational kinetic

A horizontal 808 N merry-go-round is a solid disk of radius 1.56 m, started from rest by a constant horizontal force of 50.5 N applied tangentially to the edge of the disk. Find the kinetic energy of the disk after 2.96 s.

Elongation of the rod

A force of 1.0 * 10^3 N is applied to a steel rod of length 1 m and a circular cross-section of area 10 cm^2. Find the elongation of the rod. Young's modulus for steel is 2.0 * 10^11 Pa.

Force of friction and pulling apart two books.

Two identical books each with k pages are placed on the table in a way that the each page of book A is between the pages of book b. The high half of book B is on top of book A. Given that 1) the coefficient of static friction on the surface of card A is mu; 2) Each page of the book has a mass of m; 3) Book A does not move f

Force and Center of Mass

A person holds a bowling ball in his hand with his forearm horizontal. The bowling ball has a mass of 5.10 kg and the mass of the forearm is 1.50 kg. The bicep muscle is attached to the bone of the forearm at a point d=3.00 cm from the elbow joint and the bowling ball is L=35.0 cm from the joint. Model the center of mass of the

Physics and Friction Forces

Find Fmin, the constant force with the least magnitude, that must be applied to the board in order to pull the board out from under the box (which will then fall off of the opposite end of the board).

Vertical springs in series or parallel

Prove that when two springs are attached one at the end of the other, the coefficient of the final spring becomes 1 / (1/k1 + 1/k2 ) where k1 and k2 are the coefficient of the two individual springs, the direction of the springs is VERTICAL not horizontal. Then consider two systems of springs, one in which a mass m is attached t

Euler Equation

Please see the attached PDF file. I would prefer a solution in PDF format. Thank you!

Bone Elasticity

Young's modulus for bone is about 1.0 x 10^10 Pa. Bone can take only about a 1.0% change in its length before fracturing. a) What is the maximum force that can be applied to a bone whose minimum cross sectional area is 3.0 cm^2? b) Estimate from what maximum height a 70 kg person (one weighing about 150lb) could jump an

Average Force Exerted by Ground if Man Falls out of a Window

"A 74.3 kg man steps out a window and falls (from rest) 1.01 m to a sidewalk. If the man falls with his knees and ankles locked, the only cushion for his fall is a 0.488 cm give in the pads of his feet. Calculate the average force exerted on him by the ground in this situation. This average force is sufficient to cause cartilage

Spring constant of bungee cord

"A 61.2 kg bungee jumper jumps from a bridge. She is tied to a 11.2 m long (unstretched) bungee cord and falls a total of 32.4 m. Calculate the spring constant k of the bungee cord." Here's how I approached this question: (1/2)(k)(x^2) = mgH k = 2mgH/x^2 k = (2)(61.2)(9.8)(32.4)/11.2^2 = 309.8 N/m But this is not the

Force Applied at an Angle Calculations

"A student's car stalls right in front of a speed bump while she is on her way to physics class. To pull it over the bump, she ties a cable to her bumper and to a nearby tree, and pulls with a force, F, of 70.0 pounds (311 N) at the midpoint in a perpendicular direction. If theta is 12.4 degrees, what is the size of the force pu

Two springs can be combined in series or in parallel

SEE ATTACHMENT #1 for a diagram of the springs and both arrangements. Spring A has force constant kA= 60 nt/m. Spring B has force constant kB= 40 nt/m. The two springs attached end to end form a series combination with force constant Ks. The two springs attached side by side so that a force applied to the ends stretches bo

Find the speed of the bullet after it has passed through a block.

A 3gm bullet with a speed of 300m/sec is fired on a 400gm block initially at rest. The bullet passes through the block and as a result the block begins to move with a speed of 1.5m/sec in the original direction of the bullet. Find the speed of the bullet after it has passed through the block.

Guitar strings' lengths, relative densities and frequencies

Given two guitar strings' lengths and relative densities, find information about their frequencies and tensions. The thinnest string on a certain guitar has a linear density one fifteenth the linear density of the thickest string. Both strings are the same length, L= .64 m. NOTE: On a musical scale a note one octave higher

Finding Moment of Inertia: Hollow Cylinder Example

A uniform hollow cylinder such as a roll of paper towels, has mass M, inner radius Ri, outer radius Ro. By applying 'I= Int (r^2 dm)', find its moment of inertia about a center of mass axis along its diameter. See attachment for diagram.

Velocity, conservation of momentum, force, force of gravity

1. A ball is thrown in the air with enough force so that it goes straight up for several seconds. a. What is the velocity of the ball 1 sec before it's highest point? b. What is the change in velocity during this 1 sec interval? c. What is the velocity 1 sec after it reaches it's highest point? d. what is the change in veloc