Work and energy Definition and 332 Threads

I am attempting 3 questions I have worked them out but to no avail. I wonder if I am on the right track: 1st Question: Starting from rest at the top, a child slides down the water slide at a swimming pool and enters the water at a final speed of 5.00 m/s. At what final speed would the...

I believe I have part A correct, but I have having some trouble with part B. A 63-kg skier coasts up a snow-covered hill that makes an angle of 25° with the horizontal. The initial speed of the skier is 6.6 m/s. After coasting a distance of 1.9 m up the slope, the speed of the skier is 4.4...

hi, here's the Qns, A 100-lb block of ice slides down an incline 5.0 ft and 3.0 ft high. A man pushes up on the ice parallel to the incline so that is slides down at constant speed. The coefficient of friction between the ice and the incline is 0.10. Find (a) the force exerted by the man...

A 60.0 kg crate, starting from rest, is pulled across the floor with a constant force of 100.0 N. For the first 10.0 m the floor is frictionless and for the next 10.0 m the coefficient of friction is 0.20. What is the final speed of the crate? Is it possible to use KE + PE = KE + PE...

A 4.6 kg block is pushed 5.6 m up a rough 37° inclined plane by a horizontal force of 75 N. If the initial speed of the block is 2.2 m/s up the plane and a constant kinetic friction force of 25 N opposes the motion, *calculate the following: A) the inital KE of the block B) the work done by the...

Hey, I am new and i am hoping someone can give me a hand. I desperately need assitance on this question and any advice would be great. Thanks A skier starts at rest on the top of a strange, smooth, icy hill shaped like a hemisphere. The hill has a constant radius of R. Neglecting friction (it...

Tarzan and Jane, whose total mass is 140.0 kg, start their swing on a 6.0 m long vine when the vine is at an angle of 30.0° with the horizontal. At the bottom of the arc, Jane, whose mass is 50.0 kg, releases the vine. What is the maximum height at which Tarzan can land on a branch after his...

a mass "m" slides without friction along a looped apparatus. If the object is to remain on the track, even at the top of the loop (whose radius is "r") from what minimum height "h" must it be released?

Please let me know if I am on the right track for these problems. 1) A weight lifter picks up a barbell and 1. lifts it chest high 2. holds it for 5 minutes 3. puts it down. Rank the amounts of work W the weight lifter performs during this three operations. Label the quantities as W1...

1.A 50.3-g golf ball is driven from the tee with an initial speed of 40.6 m/s and rises to a height of 29.9 m. (a) Neglect air resistance and determine the kinetic energy of the ball at its highest point. (b) What is its speed when it is 6.17 m below its highest point? a. KE=1/2mv^2 i used...

Here they are... (1) A hand exerts a constant horizontial force on a block that is free to slide on a frictionless surface. The block starts from rest at point A, and by the time it has traveled a distance d to point B it is traveling with speed vB. When the block has traveled another...

Problem with Kinetic Enery 1) A 285-kg load is lifted vertically with an a = 1.060 g (1.57m/s^2), by a single cable. Determine (a) the tension in the cable (b) The net work done on the load (c) work done by the cable on the load (d) work done by gravity on the load (e) final speed of the load...

My answers have ******** next to them. 1. A woman holds a bowling ball in a fixed position. The work she does on the ball Choices: a) depends on the weight of the ball. b) cannot be calculated without more information. c) is equal to zero. ************************ 2. When...

How much work is required to stop a 1000 kg car traveling at 100 km/hr? What I was thinking was that I would use the formula for KE, KE=1/2mv2 (last two of course is for squared since the KE would equal work. I have gotten as far as: KE= 1/2(1000 kg)(100km/hr)2 I am...

Hi, I also need help on this problem: 1. A 384-kg crate hangs from the end of a 11.2 m long rope. You pull horizontally with a varying force to move it a distance d = 5.4 m to the right. a.) What is the magnitude of the applied force F when the crate is at rest in its final position? b.)...

Alright-- Sorry, I have a couple I'm stuck on... ...I'm still a little slow with this, so I make a lot of stupid mistakes-- If you see one, by all means, please let me know. (Also, pardon the incredibly stupid nature of some of the problems... They're ridiculous) 1.) Your cat "Ms." (mass...

K. if anyone is able to help me with this problem, that would be great. A student carries a 1.0 kg physics book 3.0 m across the room, then lifts it 1.5 m to put it on a shelf. The entire task takes 20 s. a) what is the total work done on the book? b) what is the change in...

I need to know if my answer is correct for the following problem. A 2.04 kg block slides down a ramp from a height of 4.77m. If friction does 20J or work, what is the speed at the bottom of the ramp? I keep getting 9.7m/s. Is this correct?

Something is bugging me... Is there something wrong with thinking that if an object A exerts a constant force F on object B, through a distance d, then A transfers F*d joules of energy to B? Consider a situation in space... an astronaut mass m, and a rock m (no other objects anywhere). The...

work and energy problem! can someone help me explain this problem? http://docushare.capousd.org/docushare/dsweb/GetRendition/Document-158/html thanks ..

A 2 kg metal plate slides down a 10m high slope. If the slope is 49 degrees, and the speed at the bottom is 8m/s what is the coefficient of friction? This is what I tried: Wf = F x d I found the work done by Eg = Ek+Wf and then found d with 10/cos49... then I tried M = Ff/Fn (Fn found by...

Formula assistance, can anyone assist? A basketball player makes a jump shot. The 0.534-kg ball is released at a height of 2.01 m above the floor with a speed of 8.95 m/s. The ball goes through the net 3.48 m above the floor at a speed of 4.87 m/s. What is the work done on the ball by air...

Two blocks, A(50kg) and B(100kg) are connected to a string. The pulley is frictionless and of negligible mass. The coefficient of kinetic friction between block A and the incline is Mk =0.25. Determine the change in the kinetic energy of block A as it moves from C to D, a distance of 20m up...

1) How much work does it take to accelerate an electron(mass=9.11x10^-31kg) from rest to a speed of 5.0x10^6 ms? I know you have to use more than 1 equation to solve it but I can't seem to get close to an answer. 2) How much work must be done to stop a 1000-kg car traveling at 100km/h...

Question: The 20 lb block B rests on the surface of a table for which the coefficient of kinetic friction is 0.1. Determine the speed of the 10 lb block A after it has moved downward 2 ft from the rest. Neglect the mass of the pulleys and cords. Picture Attached Equation: T1 +...

A particle of mass m is attatched to 2 identical springs on a horizontal frictionless table. both springs have spring constant k and an unstretched length L the particle is pulled a distance x along a direction perpindicular to the initial configuration of the springs, show that the force...

A particle of mass m is attatched to 2 identical springs on a horizontal frictionless table. both springs have spring constant k and an unstretched length L the particle is pulled a distance x along a direction perpindicular to the initial configuration of the springs, show that the force...

A cyclist and her bicycle have a combined mass of 75 kg. she coasts down a road inclined at 2.0 degrees with the horizontal at 4.0 m/s and coasts down another road inclined at 4.0 degrees at 8.0 m/s. she then holds on to a moving vehicle and coasts on a level road. what power must the vehicle...

Okay, I have this problem that I've been having trouble with. It seems like a simple problem, but I keep getting the wrong answer and I don't know where I'm making the error. Maybe one of you can help me target the problem. =) The problem is as follows: Well, firstly I converted the 50.0...

Someone please help me to do these problems below...show me what foruma/ integral to use... Thank you very much. 1) A cable 600 ft long that weighs 4 lb/ft is hanging from a windlass. How much work is done in winding it up? 2) A 5-lbs monkey is attached to the end of a 30-ft hanging chain...

I have no idea how to do this question A tennis ball, starting from rest, rolls down the hill in the drawing. At the end of the hill the ball becomes airborne, leaving at an angle of 35° with respect to the ground. Treat the ball as a thin-walled spherical shell, and determine the range x...

I'm having trouble solving a problem related to work done on an object with friction present. Any help would be appreciated. Here's the question: A 15.0 kg block is dragged over a rough, horizontal surface by a 82.0 N force acting at 20.0° above the horizontal. The block is displaced 5.50 m...