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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.)

A platform in equilibium with torques.

A uniform, level platform whose weight is P= 260 nt is held up by a vertical rope at one end ant a vertical cable at the other end. The length of the platform is L= 4.6 m. A painter whose weight W= 825 nt stands at a distance d=1.4 m from the rope. See ATTACHMENT for diagram of parameters. Find C, the force in the cable.

Angles of twist

Two thin-walled circular tubes, one having a seamless section, the other a split section (see attachment), are subjected to the action of identical twisting moments. Both tubes have equal outer diameter "Do", inner diameter "Di", and thickness "t". Determine the ration of their angles of twist.

The rope remains perpendicular to the crate at all times

Determine the force F required to begin to move the crate up the incline. In addition you are to determine the maximum height (y) that the rope can be attached to the crate. The rope remains perpendicular to the crate at all times. (see diagram in attached file)

Torque Exerted by Pressure

A box with length L= 1.2 m, width W= 2 m, and height S = 1.5 m, has its top, movable surface hinged at its edge. SEE ATTACHMENT#1 for diagram. Fig. 2 shows the box on the bottom of the ocean with its hinged top surface horizontal at distance h= 30 m beneath the surface. The ocean density at this location is D= 1025 kg/m^3.

Physics: Rotational Dynamics

** Please see the attached file for the related illustration ** A constant horizontal force of 10 N is applied to a wheel of mass 11 kg and radius 0.70 m as shown in Fig. 12-31. The wheel rolls without slipping on the horizontal surface, and the acceleration of its center of mass is 0.55 m/s2. (a) What are the magnitude an

Moment of inertia: Force of fish on the line; how much line unwinds?

A cylindrical fishing reel has a moment of inertia of I = 6.81à?10^-4 kg* m2 and a radius of 3.13 cm. A friction clutch in the reel exerts a restraining torque of 1.49 N*m if a fish pulls on the line. The fisherman gets a bite, and the reel begins to spin with an angular acceleration of 63.7 rad/s^2. 1) What is the force of

Hydraulic Circuit Diagram

The sketch attached shows a digger. Its overall mass is 5 tonnes. The extension of the arm is controlled by three cylinders, A, B and C. Cylinder A supports the arm from the chassis of the vehicle and cylinder C is between the bucket and the main arm. Draw a hydraulic circuit diagram for the control of the three cylinders su