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Turbomachinery: Impulse & Reaction Turbines

Question 4: An impulse air turbine has a total (on static) inlet pressure and temperature of 11,25 bar, 600 degrees K and exhausts to the atmosphere at 0.91 bar. The nozzle efficiency is 87% and its exit angle is 71 degrees. The rotor efficiency is 65%. If the blade speed if 190 m/s at the mean radius of 12cm, calculate the powe

Angular Speed and Velocity

A merry-go-round makes 24 revolutions in a 3.0-min ride. (a) What is it's average angular speed in rad/s? (b) What are the tangential speed of two people 4.0 m and 5.0 m from the center, or axis of rotation?

Solving for Harmonic Motion

Question: A body oscillates with simple harmonic motion along the x-axis. Its displacement varies with time according to the equation x=5(pi/t +pi/3). The velocity (in m/s) of the body at t=1 second is equal to what value?

Centripetal force: Force exerted by the rope

A 50 kg ice skater is moving at 5m/s when she grabs the loose end of the rope,the opposite end of which is tied to a pole.She then moves in a circle of radius 1M around the pole.What is the force exerted by the rope on her arms? I think F=M*V^2/r =250N am I right?

Linear Momentum of a Billiard Ball

A billiard ball approaches the rail at a speed of 15 m/s and an angle of 60 degrees, but rebounds at a speed of 10 m/s and an angle of 50 degrees. What is the change in momentum and use components?

Paths Through a Uniform Magnetic Field, Solenoids and Net Magnetic Field

1) The figure (*see attachment) shows 11 paths through a region of uniform magnetic field. One path is a straight line; the rest are half circles. The table (*see attachment) gives the masses, charges and speeds of the 11 particles that take these paths through the field in the direction shown. Which path corresponds to which pa

Rates of Change : Velocity and Displacement

1.) Suppose a car starts from a stop sign and moves along a straight road. Assume the distance traveled in t seconds is given by s (t) + t^2 = 3t. a.) How far has the car traveled after 5 seconds? [ find s(5) ] b.) The speed of the car at exactly 10 seconds after "flooring it", can be estimated by finding the average speed

Dynamics (Angular Velocity, Angular Acceleration)

2 practice quiz problems which I need help on. Please give explanation of each problem as well as the answer: 1) Member AB rotates about pin A at a constant 10 rad/s. What is the acceleration of point C at the instant shown? a) 13.4m/s^2 b) 7.51m/s^2 c) 17.2 m/s^2 d) 11.5 m/s^2 e) 9.63 m/s^2 2) Wheel A rotates counte

Noether's theorem

Translate Noether's theorem into Hamiltonian mechanics. That is, define a symmetry for Hamiltonian mechanics (by translating the Lagrangian-definition), and prove that symmetries give rise to conserved observables.

Kinematics Physics Experiments

Francesca, who likes physics experiments, dangles her watch from a thin piece of string while the jetliner she is in takes off from Dulles Airport . She notices that the string makes an angle of 25° with respect to the vertical while the aircraft accelerates for takeoff, which takes about 13.5 seconds. Estimate the takeoff spee

Free Fall Speed Height

A student drops a ball from a height of 14.0m. How long does it take to hit the ground? What is its speed just as it hits the ground?

Wave parameters and equation

1) A transverse traveling wave on a cord is represented by D = 0.48 sin (5.6x +84t) where D and x are in meters and t in seconds. For this wave determine (a) the wavelength (b) the frequency (c) velocity (magnitude and direction) (d) amplitude and (e) maximum and minimum speeds of particles of the cord.

Projectile Motion - Magnitude and Angle

A light plane is headed due south with a speed relative to still air of 280 km/h. After 1 hour, the pilot notices that they have covered only 150 km and their direction is not south but southeast. What is the wind velocity? Find the magnitude (km/h) and angle (° north of east).

A Swimmer's Projectile Motion

A swimmer is capable of swimming 0.95 m/s in still water. (a) If she aims her body directly across a 150 m wide river whose current is 0.55 m/s, how far downstream (from a point opposite her starting point) will she land? (m) (b) How long will it take her to reach the other side?(s)

Projectile Motion - Velocity, Magnitude and Direction

A passenger on a boat moving at 1.20 m/s on a still lake walks up a flight of stairs at a speed of 0.50 m/s. The stairs are angled at 45° pointing in the direction of motion as shown. What is the velocity of the passenger relative to the water? Find the magnitude (m/s) and direction (above the water). See the attached for t

Explanation of Projectile Motion

Question: A projectile is shot from the edge of a cliff 285 m above ground level, with an initial speed of vo=135 m/s and at an angle of 37.0 degrees with the horizontal, as shown in the attached figure. Please view attachment. a) Determine the time taken by the projectile to hit point P at ground level. b) Determine the ra

Finding Velocity Vectors

An airplane is traveling 890 km/h in a direction 38.5 degrees west of north. (See the attachment for the figure). (a) Find the components of the velocity vector in the northerly and westerly directions. (b) How far north and how far west has the plane traveled after 5 h?

A Ball is Thrown

(1) A ball is thrown horizontally from a height of 20.8m and hits the ground with a speed that is three times its initial speed. What was the initial speed? (2) A ball is shot from the ground into the air. At a height of 9.1m, the velocity is observed to be V = 7.9i + 5.1j in m/s (i horizontally, j upward). To what maximum he

Projectiles and Vectors Formats

1. a) A projectile is fired horizontally from a gun that is 37.0 m above the flat ground. The muzzle velocity is 275 m/s. How long does the projectile remain in the air? b) At what horizontal distance from the firing point does it strike the ground? c) What is the speed as it strikes the ground? 2. a) A watermelon has t

Issues of Friction

I'm completely lost - Could you go step by step so I can follow your logic? Thanks. 1. A crate sits on a flatbed truck. This truck, initially travelling at a velocity of 80 km/hour, comes to a stop in 22 meters. What is the minimum coefficient of static friction required between the crate and truck bed, if it is not to sli

Speed and Velocity Problem Set

1) A blink lasts 100 milliseconds. How far does one travel in meters, if the planes average velocity is 2040mph? 2) A particles position is x=5-12t+3t^2, v=6t-12. The velocity at 1 sec = 6m/s. Is it moving toward x just then? 3) What is its speed just then? 4) Is the speed larger or smaller at much later times? 5) At what

Speed and Velocity

1) Jack travels from A to B at 30mph and returns at 10mph. Jill leaves at the same time as Jack, and travels from A to B and back at a constant speed of 20mph. Who gets back first? 2) Assume that East Lak Road runs due east from the Walmart and there are markers along it, ten miles from walmart, etc. a car starts at the 12

Collision at an Angle

Two cars, both of mass m, collide and stick together. Prior to the collision, one car had been traveling north at speed 2v, while the second was traveling at speed v at an angle omega south of east. After the collision, the two-car system travels at speed v_final at an angle theta east of north. What is the angle theta with resp

Forces on Cable Segment Angles

A sign is hung from a pole with two equal cable segments making an angle of 82 degrees. What is the resultant force of both cable segments have a force of 65 lbs? A duck flies south at a velocity of 18 ft/s. If a cross wind blows west at a velocity of 5 ft/s, what is the velocity and direction the duck is flying?

Velocity within Skiing

Ben is skiing downhill at a constant 8.0 m/s when he reaches an icy patch on which his skis move with negligible friction. If the icy patch is 37 m long and drops 15 m in elevation, what is Ben's speed at the end of the icy patch?

Horizontal and Vertical Velocity

A pellet launch is found to propel a metal ball sideways a distance of 2m, when the angle of launch is 36.9 degrees. a) What do you have to do to the initial velocity- in terms of x and y components? b) What variable is common to both horizontal and verticle motion? Find the variable. c) Use the b) value to answer this: If

Head-On Collisions

In a head-on collision where the carts stick together after the collision, a) What combinations of velocities will cause two carts of the same mass to be at rest after the collision? Explain. b) What happens if a less massive cart is moving much faster than a more massive cart? Much slower? Explain. c) What mathematical defin