Problem of friction

Here is the asking problem: 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 th ...continues

From 'net torque = I alpha', and angular momentum as a cross product, express conservation of angular momentum and solve an example.

PART a. A small mass m is attached to one end of a rod of negligible mass. The other end of the rod is fixed so that the mass can move in a circle of radius R. A force F is applied tangent to the circle, giving the mass angular acceleration 'alpha'. SEE ATTACHMENT #1 for a diagram showing parameters. Apply 'net torque= I alp ...continues

Conservation of angular momentum of a sphere and ring changing to a sphere plus bars.

SEE ATTACHMENT #1 for a diagram of the system. A uniform sphere, mass M= 84 kg, radius R, has two uniform, thin, flexible bars each with mass m= 25 kg, and length half a circumference, wrapped on its surface as shown in Fig. 1. The system is rotating with a period To about a c.m. axis at center. At some instant, the bars fly o ...continues

Moment of inertia of a rod

Find the moment of inertia of a thin rod relative to the axis which is perpendicular to the rod and passes through its end, if the mass of the rod is m and its length l.

Calculating the final temperature of a gas undergoing an expansion at constant pressure, isothermally and according to the law where pv^1.25=Constant.

A perfect gas occupying 0.2 cubic meters at a pressure of 1240 Kpa and a temp of 150 deg Celsius is expanded to 0.5 cubic meters. What is the final temp if the expansion takes place in the following ways: at constant pressure, Isothermally and according to the law pv^1.25=Constant?

steam plant hp+cooling water circulated

In a steam plant the steam leaves the boiler at 2000kpa+250C deg.It is then expanded in an engine + finally exhausted into a condenser.The press+ condition of the steam at entry to the condenser are 15kpa+0.82 dry respectively.Assuming the whole of this heat drop is converted into useful work in the engine,Need engine power deve ...continues

steam+ reducing valves

Steam flows into a reducing valve with a pressure of 1400kpa+ dryness fraction ).98.It leaves the valve with a pressure of 150kpa.What diameters of inlet and outlet pipes would be required for a flow of 2270kg per hour with a velocity of 15m/s both before and after the reducing valve? assume no losses+ enthalpy per kg steam befo ...continues

Conservation of translational plus rotational kinetic energy

A cart consists of a body of mass M mounted on two uniform cylinders, each mass m, radius R. The cart is moving at velocity V at its initial location on a plane inclined at angle b. SEE ATTACHMENT #1 for a diagram showing parameters. Known values are: M=2.1 kg, m=1.8 kg, angle b= 53 degrees, V= 2.5 m/sec. PART a. Using conser ...continues

A cylinder and a frictionless block are in contact on an inclined plane. Find their acceleration down the plane.

On an inclined plane at angle b from horizontal, a frictionless block, mass m, is placed behind and in contact with a uniform cylinder of radius R and mass M. Released from rest, the two objects remain in contact as the block slides and the cylinder rolls down the plane. Find a, the acceleration down the plane of the center of ...continues

A rotating rectangular framework rearranges to form a rotating straight bar. Apply conservation of angular momentum to find the final angular velocity.

A framework consists of two thin, uniform bars of mass M= 12 kg, length L= 3 m, and two thin, uniform bars of mass m= 6 kg, length D= 3 m, forming a rectangle of length L width D. It is rotating in space with initial angular velocity Wo= 18 rad/sec. At some instant, one corner breaks loose and the bars rearrange into a straight ...continues