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Power Screws

A power square thread screw has a pitch diameter (dm) of 34mm, the lead of the screw 1 of 4mm, the frictional diameter of the collar (dc) of 40mm. The coefficients of friction are f=0.08 for the threads and fc=0.05 for the collar. the vertical load F per screw is 5 kN. How do I find the torque required to raise the load?

Free Body Diagram of a Crane

In the crane shown in the figure, the member BG weighs 600lb, which is considered to act midway between B and F. If other weights of members are neglected, what will be the forces in the two tension rods? What will be the horizontal and vertical components of the reactions at A and B? Please see attached.

Solve: Computing the Torque

A force of 30N is applied perpendicularly to the face of a door at a distance of 1.5 m from the hinge of the door. Find the torque on the door about its hinge: a. 20 n/m b. 2nm c. 45Nm d. 20Nm

Solving for Angular Accelertion

Question: F=1 N and the length of the rod is L=1m. Find the angular acceleration when theta=0, 45, and 90 degrees. (I=1/12mL^2) m=1 kg

Stress Conditions, Etc.

A simple explanation of these solutions would be much appreciated. Could you also include any relevant comment along the way to help me understand your method and this subject better? Sketches are required. Can you also include Mohr's circle? Please find the questions in the attachment below. Hope you can help with this revis

Tension weight

A 20.0 ft horizontal arm is uniform and weighs 50.0 lbs. Find the tension in the cable and the horizontal and vertical forces at the hinge for a load of 500 lbs located 5.00 ft from the right end as shown.

Rotational Dynamics and Net Torque

A 10 kg solid disk of radius 0.50 m is rotated about an axis through its center. If the disk accelerates from rest to an angular speed of 3.0 rad/s while rotating 2.0 revolutions, what net torque is required?

Magnitude of Force Applied to a Wooden Board

A force is applied to the end of a 2ft long uniform board weighing 50lbs, in order to keep it horizontal, while it pushes against a wall at the left. If the angle the force makes with the board is 30 degrees, the magnitude of the applied force F is... a. 28.9lb b. 50lb c. 100lb d. 57.7 lb

Output Horsepower and Efficiency

A fully loaded 440 V, three phase motor draws 12.4 A at 86% power factor (pf). Its speed is 1730 rpm and its torque output to a mechanical load is 29.1 lb-ft x 1.356 = 39.5 Nm. What is (a) the output horsepower and (b) the efficiency?

Strength of Materials

1. A solid round steel shaft 3 1/2 inches in diameter transmits 100 HP at 200 RPM. Determine: a. Torsional stress in the outer fibers b. Angle of twist per foot of shaft c. Increase in stress at the outer fibers if the shaft is made hollow with a 1 1/2 inch bore. d. Stress at the inner fibers of the hollow shaft. e. Angle

Calculating Output Voltages

A steel tube, 24mm OD and 20mm ID is used to create a torque sensor. Four gauges are fitted to the tube in a bridge configuration and the bridge is supplied from a 10V source. Gauge Factor = 2.125 Shear modulus for steel = 82GN/m^2 Young modulus for steel = 210 GN/m^2 Max shear strain = 1000x10^-6 What is the output vo

Force Diagram, Tension and Torque Problem

A heavy pole, of mass M and length L, is freely hinged to a wall at the point O. A rope connects the other end of the pole, B, to a fixed point A on the wall above O. The system is in equilibrium, with the pole making an angle of θ with the horizontal, and the rope making an angle α with the horizontal... (i)Draw a for

Dynamics Problem - Torque, Acceleration, and Angular Velocity

An electric motor is running at 1200rpm when its power is cut off for 40 seconds, then turned back on. If the rotor weighs 60lb, has a radius of gyration of 8in, and experiences a power-on net torque of 100lb/in and power-off friction torque of 8lb/in, the rotational speed in rpm of the motor 2 seconds after the power is turned

Dynamics Problem - Torque and Acceleration

A motor/hoist lifts a weight at B with the ideal pulley and rope system shown (*see attached). For the information given, the acceleration of B in ft/s[squared] is what? a. 9.2 b. 0.0 c. 4.6 9. 6.3 *Please see attachment for diagram and please show your work.

Winding Drum of Lift

In the figure (attached), the winding drum of a lift is driven by an electric motor via a gearbox having a reduction ratio of 20:1. The direct inertia on the motor shaft is 0.05 kg m2 and that on the winding shaft is 20 kg m2. The drum, which has a diameter of 600 mm, moves a lift by means of a cable wound around it. If the li

Applied Mechanics

A solid shaft 125mm did transmits 600kW at 300 revolutions/minute. It is also subjected to a bending moment of 9kN-m and to an end thrust. If the maximum principal stress is limited to 80MPa, determine the permissible end thrust. Also, determine the position in which the principal stress acts, and draw a diagram showing the p

Moving a Sliding Dresser

Sam is trying to move a dresser of mass m and dimensions of length L and height H by pushing it with a horizontal force F applied at a height h above the floor. The coefficient of kinetic friction between the dresser and the floor is k and g is the magnitude of the acceleration due to gravity. The ground exerts upward normal for

Wound Rotor Induction Motor Question

A 100 hp 60 Hz six pole 460 V three phase wound rotor induction motor develops a full-load torque at 1152 r/min with the rotor short-circuited. An external noninductive resistance of 1 Ohm is placed in series with each phase of the rotor, and the motor is observed to develop its rated torque at a speed of 1116 r/min. Calculate

Three-Phase Induction Motor

A three phase Y-connected 480 V (line to line) 30 hp 60 Hz four pole induction motor has the following equivalent circuit constants in Ohms-per-phase referred to the stator: R1=0.21 R2= 0.20 X1=1.2 X2=1.1 Xp=39 The total friction windage and core losses may be assumed constant at 1340 Watts. The motor is connected directl


Help the military to launch aerial targets. The proposed device is based on an ancient engine of war - a trebuchet... 1. How fast must the target be moving when it leaves the bucket so that it it peaks 40 feet above B? How far to the left of B will it reach this peak? 2. What is the moment of inertia of the trebuchet (pipe, c

The inner hub of the wheel rests on the horizontal track.

The inner hub of the wheel rests on the horizontal track. If it does not slip at A, determine the speed of the 10-lb block in 2 s after the block is released from rest. The wheel has a weight of 30 lb and a radius of gyration kG = 1.30 ft. Neglect the mass of the pulley and cord. Please refer to the attachment for diagram.

Caculate Tension Problem / Incline Plane and Pulley Problem

Please see attachment. 1. A 70 kg painter standing on a long 5.5 m board which suspended from 2 vertical ropes attaches to each end of the board. Board is 15 kg. If the painter stood 1.5 m from one end of the board what will be the tensions in ropes? 2. We have system with incline plane and pulley. Incline plane: angle

Induction motor typical calculation.

A three-phase 230 V, 30 hp, 60 Hz, six-pole induction motor is operating with a shaft load that requires 21.3 kW to cross the air gap to the rotor. Rotor copper loss 1.05 kW, and mechanical and stray load losses are 300 W. Determine: a. shaft speed; b. mechanical power developed; c. developed torque; d. shaft torque; and,

Torque and center of mass

A person exerts a force of 38N on the end of a door 96cm wide. What is the magnitude of the torque if the force is exerted (a) perpendicular to the door and (b) at a 60.0° angle to the face of the door? *note: Please explain this in the simplest terms possible for me. Thank you so much :)

Bouyancy, Closed Vessels and Mass

A) See attachment: Metal part, 2, is attached by a thin cord from a floating wood block, 1. The wood block has a specific gravity(S.G.)=0.3 and dimensions of 50x50x10mm. The metal part has a volume of 6600mm^3. Find mass, m2, of metal part and the tension, T, in the cord. B) See attachment: The closed vessel has water of a

Feedback Control Systems: Systems Specifications

Find a second order model to achieve the following response to a step output disturbance of height 0.5. Minimum value 0.05 after 0.1s. Make a rough sketch of the bode magnitude plot and the step response. (Please see attachments for details.)