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    Thermodynamics - Calculate power and dimensions of piping

    Homework Statement 500 kg/hr of steam drives a turbine. The steam enters the turbine at 60 bara and 500C at a linear velocity of 5.0 m/s. After driving a set of turbine wheels to generate shaft power, the steam exhausts from a pipe that is 10 m below the entrance pipe at 35.0 m/s and at 2.5...
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    Calculating the mass of the wheel on a pendulum on a watch

    Homework Statement The balance wheel of a watch is a thin ring of radius 0.95 cm and oscillates with a frequency of 3.10 Hz. If a torque of 1.1x10-5 Nm causes the wheel to rotate 45°, calculate the mass of the balance wheel. Homework Equations I=mr2 T=(2π)sqrt(I/mgh) τ=-Kθ The...
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    Simple Harmonic Motion on a Uniform Meter Stick

    Homework Statement A uniform meter stick of mass M is pivoted on a hinge at one end and held horizontal by a spring with spring constant k attached at the other end. If the stick oscillates up and down slightly, what is its frequency? Homework Equations τ=rFsinθ f=(1/2π)√(k/m) F=kx...
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    Ball rotating on axle which is rotating itself

    Homework Statement A ball of mass m is attached via a rod of length x to an axle that rotates with angular velocity ω. You can consider the ball to be a point mass. m = 5 kg, x = 0.3 m, y = 0.4 m, ω= 30 rad/s (a) What is the linear momentum (direction and magnitude) of the ball? (b) What...
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    Solid disk rolling

    Homework Statement A solid disk of mass m and radius R rolls without slipping with a velocity v. Assuming it doesn't slip, how far vertically will it roll up an incline? Homework Equations I=0.5mr2 E=0.5Iω2 KE=0.5mv2 PE=mgh The Attempt at a Solution I'm thinking that we need to...
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    PH of a solution containing a strong acid and a weak acid

    Homework Statement Find the pH in 50.0 mL of 1.00M HCl + 50.0 mL of 1.00M HF Homework Equations None to speak of really... The Attempt at a Solution I figured out [HCl] and [HF] in the solution: they're both 0.5M. I have absolutely no idea what to do at this point... Thanks.
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    Rotational motion on pulley system

    Homework Statement A string passing over a pulley has a 3.80-kg mass hanging from one end and a 3.15-kg mass hanging from the other end. The pulley is a uniform solid cylinder of radius 4.0 cm and mass 0.80 kg. If the bearings of they pulley were frictionless, what would be the acceleration...
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    Velocity of ball rolling down ramp

    Homework Statement A ball of radius ro rolls on the inside of a track of radius Ro. If the ball starts from rest at the vertical edge of the track, what will be its speed when it reaches the lowest point of the track, rolling without slipping? Included below is a link to the diagram...
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    Work done by gravity problem

    Homework Statement An object of mass m is moved straight up by a distance h. The work that gravity does on the object is: (a) -mh (b) +mh (c) -mgh (d) +mgh (e) None of the Above Homework Equations Work = ∫F dl PE = mgh The Attempt at a Solution I have a feeling the answer is (c)...
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    Kinetic and Potential Energy on a roller coaster

    Homework Statement A roller coaster starts at the top of hill that is 10 m high. If it is to barely make it to the top of a second hill that is 20 m high, how fast must the initial speed of the roller coaster be? Assume that the roller coaster is frictionless. Homework Equations KE =...
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    Conservation of mechanical energy for skier on sphere

    Homework Statement A skier of mass m starts from rest at the top of a solid sphere of radius r and slides down its frictionless surface. At what angle θ will the skier leave the sphere? Homework Equations KE= 0.5mv^2 PE = mgh Fc = (mv^2)/r The Attempt at a Solution I am really...
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    Conservation of Energy for satellite in an elliptic orbit

    Homework Statement A satellite is in an elliptic orbit around the Earth. Its speed at pedigree A is 8650 m/s. (a) Use conservation of energy to determine its speed at B. The radius of the Earth is 6380 km. Use conservation of energy to determine the speed at the apogee C. Homework...