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Laws of Motion : Connected motion

(Please see the attached file for detailed problem and fig.) The two blocks, m1 = 3.0 kg and m2 = 4.9 kg, in the figure (see attachment) are connected by a massless rope that passes over a pulley. The pulley is 12 cm in diameter and has a mass of 2.0 kg. As the pulley turns, friction at the axle exerts a torque of magnitude 0

They rotate about the center of mass

See the attached problem below. A 0.9 kg mass at (x, y) = (20 cm, 20 cm) and a 2.6 kg mass at (20 cm, 100 cm) are connected by a massless, rigid rod. They rotate about the center of mass. (a) What are the coordinates of the center of mass? (b) What is the moment of inertia about the center of mass? (c) What constant

A disc on an inclined plane

(Please see the attached file and solve number 4 only) A uniform disk of mass m=20 lb and radius r=9 inches is placed in contact with an inclined surface and a constant couple M = 7.5 lb.ft is applied as shown (see attachment). The weight of link AB is negligible. Knowing that theta = 30 degree and the coefficient of kinetic

force applied to outer edge at right angles to the door

I do not know where to begin with this particular problem. Does this involve torque since we are moving the door 90 degrees? Here's the problem: A massive shield door at a neutron test facility at Lawrence Livermore Laboratory is the world's heaviest hinged door. The door has a mass of 44,000 kg, a rotational inertia about it

Hydostatics: Force and torque on a dam wall of reservoir

As the reservoir behind a dam is filled with water, the pressure that the water exerts on the dam increases. Eventually, the force on the dam becomes substantial, and it could cause the dam to collapse. There are two significant issues to be considered: First, the base of the dam should be able to withstand the pressure rho gh,

A 1220 N uniform beam is attached to a vertical wall at one end and is supported by a cable at the other end. A 1960 N crate hangs from the far end of the beam. Using the data shown in the drawing find (a) The magnitude of the tension in the wire and (b) The magnitude of the horizontal and vertical components of the force that the wall exerts on the left end of the beam.

(5) A 1220 N uniform beam is attached to a vertical wall at one end and is supported by a cable at the other end. A 1960 N crate hangs from the far end of the beam. Using the data shown in the drawing find (a) The magnitude of the tension in the wire and (b) The magnitude of the horizontal and vertical components of the f

Simple Harmonic Motion..

A slender, uniform metal rod of mass M and length l is pivoted without friction about an axis through its midpoint and perpendicular to the rod. A horizontal spring, assumed massless and with force constant k, is attached to the lower end of the rod, with the other end of the spring attached to a rigid support. a). Find the

To determine the torsional constant of a Torsional Pendulum.

A thin metal disk of mass m = 2 x 10^-3 kg and radius R = 2.20 cm is attached at its center to a long fiber. When the disk is turned from the relaxed state through a small angle theta, the torque exerted by the fiber on the disk is proportional to theta: T= -k*theta The constant of proportionality k is called the "torsional

Sliding Ladder

A uniform ladder with mass m_2 and length L rests against a smooth wall. A do-it-yourself enthusiast of mass m_1 stands on the ladder a distance d from the bottom (measured along the ladder). The ladder makes an angle theta with the ground. There is no friction between the wall and the ladder, but there is a frictional force of

A Bar Suspended By Vertical Strings

A rigid, uniform, horizontal bar of mass m_1 and length L is supported by two identical massless strings. Both strings are vertical. String A is attached at a distance d < L/2 from the left end of the bar and is connected to the ceiling; string B is attached to the left end of the bar and is connected to the floor. A small block

maximum weight the crane lifts without tipping

Given the angle theta_min, what is the maximum weight (or load) W_L,max that this crane can lift without tipping forward? (Recall that weight has units of force.) Express the maximum load in terms of theta_min and other quanitites given in the problem introduction.

The Angular Velocity at the Start of the Interval

A variable torque is applied to a rotating wheel at t = 0 and causes the clockwise angular acceleration (alpha) to increase linearly with the clockwise angular displacement (theta) of the wheel during the next 30 revolutions. when theta is 0, alpha is 10 rads/sec^2. when theta is 30 revs, alpha is 20 rds/sec^2, and the angul

Torque Exerted About the Center of the Nut

A machinist is using a wrench to loosen a nut. The wrench is 25.0 cm long, and he exerts a 17.0 N force at the end of the handle at 37 degrees (see attachment). a) What is the magnitude of the torque does the machinist exert about the center of the nut? b) What is the maximum torque he could exert with this force?

KQML/KIF Dialogue Between Two Agentsa

This question deals with dialogue between two Intelligent Software Agents: The following is a short KQML/KIF dialogue between two agents, with respect to an engineering domain. (stream-about :sender A :receiver B :language KIF

Linear velocity of cylinders when rolling down an incline

A thin cylindrical shell and a solid cylinder have the same mass and radius. The two are released side by side and roll down, without slipping, from the top of an inclined plane that is 4.9 m above the ground. The acceleration of gravity is 9.8 m/s2 : Find the final linear velocity of the thin cylindrical shell. Answer in units

Rolling of round objects down an incline and torque

Q#1 Explain (a) how it is possible for a large force to produce only a small or even zero, torque, and (b) how it is possible for a small force to produce a large torque. q#2 A hoop, a solid cylinder, a spherical shell, and a solid sphere are placed at rest at the top of an incline. All the objects have the same ra

Tension in the Wire and the Reactions Against the Rollers

Please see attached. For some reason I have too many unknowns when solving; not sure which can be combined. The uniform bar with end rollers weighs 60 lb and is supported by the horizontal and vertical surfaces and by the wire AC. Calculate the tension T in the wire and the reactions against the rollers at A and at B.

Finding forces supporting the diving board and torque

Please see attached text file for picture. Determine the magnitudes and directions of the forces supporting the diving board (F1 and F2). Find the torque (Magnitude and Direction) due to the divers weight about the support closer to the water. (that is the support at F2 in the picture)

Forces on the Uniform Beam by the Wall and the Wire

A 1200 N uniform beam is attached to a vertical wall at one end and is supported by a cable at the other end. A W = 1940 N crate hangs from the far end of the beam. Use the data shown in the drawing to determine the following (see attachment). (a) Calculate the magnitude of the tension in the wire. (b) Calculate the magni

distance from the support before the plank begins to tip

A uniform plank of length 4.8 m and weight 211 N rests horizontally on two supports, with 1.1 m of the plank hanging over the right support (see the drawing). To what distance x can a person who weighs 458 N walk on the overhanging part of the plank before it just begins to tip?

torques due to the weight and thrust

The drawing shows a jet engine suspended beneath the wing of an airplane. The weight W of the engine is 9600 N and acts as shown in the drawing. In flight the engine produces a thrust T of 62400 N that is parallel to the ground. The rotational axis in the drawing is perpendicular to the plane of the paper. With respect to this a

Forces and Torques: Net torque applied to the cable car.

In San Francisco a very simple technique is used to turn around a cable car when it reaches the end of its route. The car rolls onto a turntable, which can rotate about a vertical axis through its center. Then, two people push perpendicularly on the car, one at each end, as in the drawing. The turntable is rotated one-half of a

Forces and Torques

You are installing a new spark plug in your car, and the manual specifies that it be tightened to a torque that has a magnitude of 47 Nm. Using the data in the drawing, determine the magnitude F of the force that you must exert on the wrench.

Torque on a loop

A rectangular wire loop with a cross-sectional area of 5,000 cm^2 carries a current of 0.50 amperes. The loop is free to rotate about an axis that is perpendicular to uniform magnetic field strength of 0.40 Tesla. The plane of the loop is initially at an angle of 25 degrees to the direction of the magnetic field. What is the ma

Hoop's Angular Velocity Moving Down an Inclined Plane

The hoop (thin ring) has a mass of 5 kg and is released down the inclined plane such that it has a backspin angular speed = 8 rad/s and its center has a velocity = 3 m/s as shown. If the coefficient of kinetic friction between the hoop and the plane is 0.6, determine the hoop's angular velocity in 1 s. (See attached file for

Atwood Machine: Finding Speed of a Mass

An Atwood machine has a mass of 3.50 kg connected by a light string to a mass of 6.00 kg over a pulley with a moment of inertia of 0.0352 kg and a radius of 12.5 cm. If the system is released from rest, what is the speed of the masses after they have moved through 1.25 m? 2.00 m/s 2.28 m/s 4.00 m/s 4.95

Oscillation of a Cylinder on a Cylindrical Surface

A small uniform cylinder of radius R rolls without slipping along the inside of a large fixed cylinder of radius r (r>R). Show that the period of Oscillation of the rolling cylinder is equivalent to that of a simple pendulum whose length is 3(R-r)/2.

Angular acceleration of the rod

In problem 16.72(a), if the uniform slender rod weighs 15 lb, and the horizontal force P is 12 lb, the angular acceleration of the rod is: a. 44.2 rad/s^2 b. 82.8 rad/s^2 c. 55.2 rad/s^2 d. 35.2 rad/s^2