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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

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.

Pulling a Cart

Please do not place your response in a .pdf or .cdx format, but Word documents are okay. Thanks! Here's the actual problem: Suppose that you have a cart with very little friction, and you pull this cart with a constant force. A) After the cart is moving, is the force that is applied to the cart by the string constant, i

Angular Velocity of Links

The velocity of the slider block C is 4 ft/s up the inclined groove. Determine the angular velocity of links AB and BC and the velocity of point B at the instant shown. Links AB and BC are both 1ft in length. (See attachment for full question.)

Angular Velocities of a Pulley

If the end of the cord is pulled downward with a speed Vc= 120mm/s, determine the angular velocities of pulleys A and B and the speed of block D. Assume that the cord does not slip on the pulleys. (See attachment for full question.)

Projectile Motion with Coefficient of Restitution

The ball is ejected from the tube with a horizontal velocity of v1= 8ft/s as shown. If the coefficient of restitution between the ball and ground is e=0.8, determine (a) the velocity of the ball just after it rebounds from the ground and (b) the maximum height to which the ball rises after the first bounce (see attachment for di

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

Calculating Recoil Velocity

Starting from rest, two skaters "push off" against each other on smooth level ice, where friction is negligible. The little one has a mass of 54-kg and the bigger one has a mass of 88-kg. Assuming the little one coasts away with a velocity of 2.5 m/s due north, determine the recoil velocity of the bigger skater.

Average Force Exerted

A 140 gram baseball has a velocity of 38 m/s as it approaches a bat. The bat applies a force and the ball departs in the opposite direction at 58 m/s. The contact time between the bat and the ball is 4.0 ms. Determine the average force exerted on the ball by the bat.

Hitting a tennis ball - the magnitude of the net impulse

The tennis ball has a horizontal speed of 15 m/s when struck by the racket. If it then travels away at an angle of 25 deg from the horizontal and reaches a maximum altitude of 10m, measured from the height of the racket, determine the magnitude of the net impulse of the racket on the ball. The ball has a mass of 180g. Neglect th

Impulse of foot kicking soccer ball

A man kicks a 200g ball such that it leaves the ground at an angle of 30 deg. with the horizontal and strikes the ground at the same elevation a distance of 15m away. Determine the impulse of his foot on the ball. Neglect the impulse caused by the ball's weight while its being kicked. **answer should be 2.61 N*s**

"Ball Kick"

A man kicks a 200g ball such that it leaves the ground at an angle of 30 degrees with the horizontal and strikes the ground at the same elevation a distance of 15m away. Determine the impulse of his foot on the ball. Neglect the impulse caused by the ball's weight while its being kicked.

Block Up Ramp

A 5-lb block is given an initial velocity of 10 ft/s up a 45 degree smooth slope. Determine the time it will take to travel up the slope before it stops.

Velocity, Distance and Speed

The 2-lb brick slides down a smooth roof, such that when it is at A it has a velocity of 5ft/s. Determine the speed of the block just before it leaves the surface at B, the distance d from the wall where it strikes the ground, and the speed at which it hits the ground.

Force, Velocity, Potential Energy (Energy Law)

A girl has a mass of 40kg and center of mass at G. If she is swinging to a maximum height defined by theta = 60 deg, determine the force developed along each of the four supporting posts such as AB at the instant theta = 0 deg. The swing is centrally located between the posts. *See attachment for diagram.

Playing with a Water Hose

Here's the problem: Two children, Ferdinand and Isabella, are playing with a water hose on a sunny summer day. Isabella is holding the hose in her hand 1.0 meters above the ground and is trying to spray Ferdinand, who is standing 10.0 meters away. To increase the range of the water, Isabella places her thumb on the hose hole

Collision: Calculating Force and Velocity

Just before it is struck by a racket, a tennis ball weighing 0.560 N has a velocity of (20.0i-4.0j) m/s. During the 3.00 ms that the racket and ball are in contact, the net force on the ball is constant and equal to (-380i+110j)N. What is the x-component of the impulse of the net force applied to the ball? What is the y-componen

Conservation of momentum

Jonathan and Jane are sitting in a sleigh that is at rest on frictionless ice. Jonathan's weight is 800 N, Jane's weight is 600 N, and that of the sleigh is 1000 N. They see a poisonous spider on the floor of the sleigh and immediately jump off. Jonathan jumps to the left with a velocity (relative to the ice) of 5.00 m/s at 30 d