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Recoil velocity calculation

A 37.0 kg child standing on a frozen pond throws a 0.500 kg stone to the east with a speed of 6.00 m/s. Ignoring friction between the child and the ice, find the recoil velocity of the child. (Assume the positive direction is to the east.) m/s

Solving for Pressure and Velocity

Question: The artery is 2/3 blocked. The normal speed is 0.40 m/s and blood density is 1060 kg/m^3. Find the velocity of the blood at the blocked area. Find the pressure difference between the normal and blocked area.

Velocities of the bowling balls after the collision

1) A 3 kg bowling ball traveling with a velocity of 3 m/s collides head-on with another bowling ball of the same mass traveling with a velocity of -2 m/s. If the collision is perfectly elastic, the velocities of the bowling balls after the collision is: a. 2 m/s an -3 m/s b. 5 m/s and 0 c/-2 m/s and -3 m m/s/s d. -2m/s and

Airplane flight wing pressure

During level airplane flight at a constant velocity, the pressure created by air flowing over the curved upper surface of the wing compared to the pressure created by air flowing along the flat underside of the wing is a. less b. insufficent data c. the same d. more

Dynamics: Speed, Velocity, Angle, etc.

1. Find the total energy of the system at the given instant if the 20 kg disc has an angular velocity of 24 rad/s (clockwise), the bar AB has a mass of 2 kg, and the system is 1.5 meters above the ground. Assume the ground as the datum line (zero potential energy). a. 353 J b. 389 J c. 294 J d. 323 J e. 429 J

Find the velocity of the block/bullet system immediately after the collision.

A 3.16 kg block of wood rests on the muzzle opening of a vertically oriented rifle, the stock of the rifle being firmly planted on the ground. When the rifle is fired, an 8.10 g bullet (velocity = 850 m/s, straight upward) becomes completely embedded in the block. (a) Using the conservation of linear momentum, find the velocity

Method of Subsitution : Velocity from Displacement and Acceleration

In science, we calculate the displacement of an object (how far it travels) and the velocity of an object (how fast it is moving) using the Displacement Equation and the Velocity Equation. where x is the displacement of the object, measured in meters t is the amount of time that we analyze the movement of the object, m

Falling steel I-beam

If a steel I-beam falls from the top of a 96 foot high building, how long before it hits the ground? (if an object is given an initial velocity v feet per second from a height of S feet it's height after t seconds is given by: S = -16t^2 + vt + s)

Momentum of a Particle

The momentum of a particle is proportional to the square of its velocity. True or false? Please also explain why.

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?

Determine the Thermal Efficiency

An aircraft is flying at true airspeed of 270m/s, each jet engine producing 10,000 lb max thrust for a fuel flow of 0.3 kg/s. Noting that the lower calorific value of AVTUR (Jetfuel) is 42 MJ/kg, determine the engine's overall thermal efficiency in this operating condition.

Linear Momentum and Collisions

Two spheres collide on a horizontal frictionless surface. The first sphere has mass 1.0 kg is initially moving at 3.0 m/sec, the second sphere has mass 2.0 kg is intially at rest. Show the algebraic steps what is the velocity of the first sphere after the collision? a) if there was an elastic collision b) if there was an

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?

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.

Free Fall Speed

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

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