# Torques

### Angular acceleration of a cylinder

A massless string is wrapped around a uniform solid cylinder with mass M = 10 kg and radius R = 0.40 m. One end of the string is attached to the cylinder and the free end is pulled tangentially by a force that maintains a constant tension T = 5 N . Find (a) the angular acceleration (b) the angular speed of the cylinder 5

### Regarding the approach to induction motor operation and how to solve the very simple problem being known some basic equations of power balance such as input power equation of IM (P=[(EV/X)sin(Angle E- Angle V)]

A 12 pole, 60 Hz synchronous machine has an internal rms voltage of 10 kV. Its internal synchronous reactance is 10 ohms. The machine is connected to a network with a terminal voltage of 11 kV rms. The phase angle difference between the internal and external voltages is 30 degrees (internal minus external). (a) Is this machi

### Difficulty over a problem of friction about sleeve

How can I solve this problem below: The asking problem: A safety device used by workers climbing ladders fixed to high structures consists of a rail attached to the ladder and a sleeve which may slide on the flange of the rail. A chain connects the worker's belt to the end of an eccentric cam which may rotate about an axle a

### An irregular flywheel is suspended on a pivot and oscillates with SHM from which we must find its moment of inertia.

A flywheel is symmetrical but irregular. SEE ATTACHMENT #1 for a diagram showing parameters. Its mass is 25 kg. When supported from a knife edge pivot, .36 m from the c. m. at its center, it oscillates as a physical pendulum completing 100 complete oscillations in 180 seconds. Find Io, its moment of inertia about the c.m. axis

### A truck is to be driven upward on a plane. Find the maximum plane angles P, Q, S

A truck whose weight is W, has a wheelbase (distance between front and back wheels) B= 3.2 meters. On level ground the front wheels carry 65% of its weight. The center of gravity (c.g.) of the truck is distance d= .85 m above the ground and unknown horizontal distance x, behind the front wheels' contact with the ground. The coef

### Calculate curb height a car can negotiate

A car is stopped with its front wheels resting against a curb when its driver starts the engine and tries to drive over the curb. Knowing that the radius of the wheels is 280 mm, that the coefficient of static friction between the tires and the pavement is 0.90, and that 60 percent of the weight of the car is distributed over it

### Find torque exerted by the sea on a submerged submarine's three escape hatches

See attached diagram. Three emergency escape hatches are on a submarine submerged in sea water whose density is D=1025 kg/m^3. Each hatch is rectangular, having width W= .85 m, length L= 1.2 m with its hinge of length W along one side. See attachment for orientation for Parts a, b, and c. PART a. The Deck Hatch is in

### Physics Pulley system: relate accelerations to angular acceration of the disk

A disk of mass M and radius R unwinds from a tape wrapped around it. The tape passes over a frictionless pulley, and a mass m is suspended from the other end. Assume that the disk drops vertically. a) Relate the accelerations of m and the disk, a and A, respectively to the angular acceration of the disk. Ans clue- If A w

### Physics: Calculate amount of torque required to keep a cylinder rotating

A cylinder of mass M and radius R is rotated in a uniform V grove (which looks like a rectangular block with an 45-45-90 degree triangular prism cut from the center- that the cylinder rotates in) The cylinder has a constant angular velocity w and a coefficient of friction u with each surface. What torque must be applied to the c

### Physics Falling Stick: Torque, angular acceleration, vertical acceleration

A uniform stick of mass M and length l is suspended horizontally with end B on the edge of a table, and the other end, A is held by hand. Point A is suddenly released. At the instant after release: a) What is the torque about B? b) What is the angular acceleration about B? c) What is the vertical acceleration of the center

### Physics: Sphere and Cylinder having different accelerations down a plane.

See attachment #1 for diagram showing parameters At the upper end of an inclined plane of length L, a uniform sphere is released from rest. At the same instant, a uniform cylinder is released from rest at distance d ahead of the sphere such that both sphere and cylinder arrive at the same time at the lower end of the plane.

### Working with force and mechanical advantage.

A 1m long crowbar is used to lift a heavy crate. The pivot point is 10 cm from one end. a) If 600 N is exerted on one end, what is the upward force exerted on the crate at the other end? b) Calculate the mechanical advantage, the ratio of forces.

### What net torque is being applied to the blades?

The blades of a ceiling fan have a total moment of inertia of 0.16kg*m^2 and an angular acceleration of 7.0 rad/s^2. What net torque is being applied to the blades?

### True Statements

Shown below are seven situations where a student is holding a meter stick at the left end at various angles. A 1.0 kg mass is hung on the meter sticks at different locations. The meterstick is held stationary in all cases. All of the meter sticks are identical, but the distance along the meter stick at which the 1.0 kg mass is h

### Determining how to exert the greatest torque on a tree.

A rope 20m in length is attached to a tree to pull it over. How far up the trunk of the tree should the rope be attached to exert the greatest torque?

### Calculating the holding torque in a gear box.

A gear box has the input power 10kw at 2400 rev/min. The gear ratio is a reduction of 2 to 1. The efficiency is 98%. What is the holding torque required?

### Mathematical Modelling of a Controlled Cart on a Horizontal Pivoting Beam

Use Newtons Law to derive equations of motion for the system. This should be converted into transfer functions for input into MATLAB/SIMULINK. The system consists of a motorised trolley on a see-saw (see attached figure). The trolley motor is to be controlled and eventually the trolley must balance the beam. A potentiometer s

### Mechanics problem - rolling

A uniform rigid disk of radius r and mass m rolls without slipping on a smooth horizontal surface. A constant force of magnitude P is applied to the rim of the disk at distance r above the horizontal surface and in the direction of motion. r,m,P are known. what is the angular acceleration in terms of known quantities, and wha

### Find the starting torque, the maximum torque, and the speed at maximum torque for a 3 phase, 50 Hz, 6 pole wound rotor induction machine.

A 3 phase, 50 Hz, 6 pole wound rotor induction machine has the following per phase parameters: Rs = Negligible Ls = 0.003 H Rr = 0.3 Ohm Lr = 0.002 H Lm = 0.1 H Rc = Infinity Ns/Nr = 1.2 The voltage applied to each phase is 240 Vrms. Find: the starting torque, the maximum torque, and the speed at max