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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

Projectiles and Vectors

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


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

String Attached to a Block on a Horizontal Surface

Consider a string attached to a block on a horizontal surface. If you gradually pull very gently and horizontally on the string and increase the force very slowly until the block moves at a constant velocity. What happens to the frictional force just as the block begins to slide? Explain.

Average Landing Force Needed

A person about to jump from a 1.6m high platform wants to limit the average stopping force on landing to 12 times her weight. By how much will it be necessary to lower herself by flexing her knees? Give an algebraic rather than numerical answer. Compare that work with the original potential energy she had before she jumped.

Physics Wave Problems

11. A particle in simply harmonic motion has a frequency of 40 Hz. What is the period of this oscillation? 17. (a) At what position is the speed of mass in a mass-spring system maximum? (1) x = 0, (2) x = -A, or (3) x = +A. Why? (b) If m = 0.250 kg, k = 100 N/m, and A = 0.10 m, what is the maximum speed? 33. The simple pe