Skateboard Definition and 35 Threads

Hi all, I wonder if someone can help me with a calculation/estimation? I have recently built a skateboard press to...press skateboards! My question is, how do I calculate how much pressure is being applied to the skateboard? Most presses are steel, however, not having any metal working skills...

As you can see in the pictures below the trucks are attached to the skateboard with four screws nuts and bolts, with a 2~3mm piece of rubber between the truck and the board. I've always wondered if tightening the screws bolts harder, decreases or increases the strength of the 7-layered plywood...

I've calculated the potential energy at the top of the halfpipe, before the boarder drops in: PE = 39.5 kg * 9.8 m/s^2 * 3.66 m = 1416 J Since the boarder would have no potential energy and all kinetic energy at the bottom of the halfpipe, KE = 1/2mv^2 = 1416 J 1/2 (39.5 kg) (v^2) = 1416 J So...

Hi, I'm making an electric longboard and trying to write an app for my phone to function as the remote. I've got a bunch of fancy Star-Trek-esque indicators on it, one of which is the pitch and roll of the deck. All the indicators have "danger zones" and turn red when they hit them, and for this...

Hi everyone, My roommate and I were talking about which would win in a short downhill race (with no pedaling from either rider), a bike or a skateboard. Assuming the bike stays in the same gear (2, and 4), and has a wheel diameter of 27", and the skateboard has a wheel diameter of 2.4". My...

Hi, I understand the mechanics of jumping straight up and landing on the same spot when inside of a moving bus traveling at a constant velocity but what happens when I jump straight up when skateboarding downhill? Do I land on the same spot on the skateboard, do I land further back relative to...

I don't want any medical advice so please don't give it. I've got the best medical team in the country taking care of me. So please don't shut down this thread. I have a large number of fans on this site, deservedly so, who want an update of my condition. Yes, I had a skateboard accident...

I haven't skateboarded since the late 70's with the Dog town and Z-boyz. I'm typing with my left hand, my right hand is killing me. The wrist. its all swollen. it's horrible, all swollen. Bad accicent at skateboard park. it's gross, it's all pffed up a\nd i can't move it, this sucks. yu...

Homework Statement A 48.0-kg boy, riding a 1.60-kg skateboard at a velocity of 5.80 m/s across a level sidewalk, jumps forward to leap over a wall. Just after leaving contact with the board, the boy's velocity relative to the sidewalk is 6.00 m/s, 7.40° above the horizontal. Ignore any friction...

I'm building an electric skateboard. I am trying to calculate the bare minimum force and torque to move a 180 lb object on 4 polyurethane wheels from standstill for motor selection. I got lost in finding the coefficient of friction for polyurethane wheels and whether I am using the equation for...

A person stands still on skateboard. He then jumps off at a velocity of 3 m/s. His mass is 50 kg and the skateboard has a mass of 3.5 kg. At what velocity does the skateboard shoot off?2. Is my answer correct? If not what did I do wrong?3. m1v1=m2v2 V= 42.857 m/s

Fiona rides her skate board up a ramp. She begins with a speed of 8.0m/s but slows with a constent deccsalerarion of 2.0m/s. She tracked some distance up the ramp before coming to rest, then rolled down again. Ignoring air resistance and friction; calculate. A) the distance that Fiona travels up...

Homework Statement Dan is gliding on his skateboard at 3.00m/s . He suddenly jumps backward off the skateboard, kicking the skateboard forward at 6.00m/s (as measured by an observer on the ground). Dan's mass is 40.0kg and the skateboard's mass is 5.00kg . How fast is Dan going as his feet hit...

Homework Statement A person sits on a skateboard and wants to propel themselves. The persons mass is 150 lbm whihile the skateboard mass can be ignored. The person has a bucket with 1 kg rocks totaling 10 kg. The rocks are ejected at a rate of 1 kg/s and a velocity of 108 mph with respect to...

I am to compete in an upcoming skateboard marathon. Recently we were discussing the use of skateboard wheels and whether the circumference of the wheel had any advantage given that a larger wheel would also generally mean a heavier wheel and would require more force to push it. The skateboard...

Homework Statement The coefficient of friction is to be found from a skateboard and rider rolling down a ramp, which has an angle of 5 degrees. The skateboard accelerates at .5308 m/s^2. The mass of the rider and skateboard is 91.3 kg, or 895 Newtons. The other data would be gravity...

I was just wondering if a flying skateboard would be possible to make in this time and day. I don't mean a hover board which uses anti-gravity mechanic, but a flying skateboard which uses a turbojet engine. I really want to make one, but I am not sure if it is even possible in the first...

Homework Statement A 0.50 kg skateboard is at rest on a rough, level floor on which two lines have been drawn 1.0 m apart. A constant horizontal force is applied to the skateboard at the beginning of the interval, and is removed at the end. The skateboard takes 8.5 s to travel the 1.0 m...

I am trying to get new wheels for my skateboard and I am trying to make it so that I can travel around the university at the fastest rate and one of my goals it to make it so that from an initial push F it can travel the furthest. So I am trying to reduce the Friction force. I am no expert in...

Homework Statement [PLAIN]https://dl.dropbox.com/u/9215647/webassign%20s.JPG Rank the slopes (greatest first) according to the work done on the skater by the gravitational force during the descent on each slope, Homework Equations work=change in potential energy, ie. delta U =...

I've been having a bit of a discussion with a friend lately, about an object dropping off a horizontal surface, falling a certain amount, and then landing on another horizontal surface. The question is whether the impact of landing on the horizontal surface, will be affected by the velocity...

Homework Statement A skateboarder on a horizontal surface can accelerate from rest just by moving the body, without touching external support. Investigate the parameters that affect the motion of a skateboard propelled by this method. 2. The attempt at a solution I think that...

Homework Statement A 43.9 kg student runs down the sidewalk and jumps with a horizontal speed of 4.03 m/s onto a stationary skateboard. The student and skateboard move down the sidewalk with a speed of 3.85 m/s. a) find the mass of the skateboard. answer in units of kg b) How fast would the...

Homework Statement A skateboarder on a horizontal surface can accelerate from rest just by moving the body, without touching external support. Investigate the parameters that affect the motion of a skateboard propelled by this method. Homework Equations Don't know what variables I can...

So.. I am sick and tired of high gas prices and have decided to build an electric skateboard as a secondary method of transport. Main issue is that I have no engineering experience at all and am having problems finding formulas to calculate how long the battery will last. Can anyone...

Homework Statement Jess, who weighs 50 kg, is riding a 10 kg skateboard. The skateboard and Jess are moving east at 5 m/s. Jess falls off the skateboard and hits the ground at 4 m/s east, relative to the ground. Calculate the velocity of the skateboard. Homework Equations The...

Hello, Say you have a frictionless setting. In this setting are two skateboards. One has a waterwheel (or any wheel with fins) propped up on beams so that it is on the skateboard and can freely turn. On the other skateboard is a person standing on it. If the skateboards are one behind the...

Hey I'm a skateboarder and been skaten for a while and I have recently been trying to spin as many times. So what do I have to do to keep my speed and momentome? Also is there a rule for momentome that applies to everything? By the way my I'm in Physics but my teacher is a crazy old...

Hey all, I'm having a little trouble finding infomation on skateboard physics. More specifically, i need to find out the different physics concepts (ie. forces) that act on skateboards and their wheels. How does friction effect the performance of skateboards and how are skateboards designed...

Potential energy and a skateboard, only have until 11:30! A 54.5 kg. skateboarder starts out with a speed of 1.95 m/s. He does +80.0 J of work on himself by pushing with his feet against the ground. In addition, friction does -265 J of work on him. In both cases, the forces doing the work are...

Potential energy and a skateboard, only have until 11:30! A 54.5 kg. skateboarder starts out with a speed of 1.95 m/s. He does +80.0 J of work on himself by pushing with his feet against the ground. In addition, friction does -265 J of work on him. In both cases, the forces doing the work are...

Matt is gliding on his skateboard at 4.00 m/s. He suddenly jumps backward off the skateboard, kicking the skateboard forward at 8.00 m/s. Matt's mass is 50 kg and the skateboard's mass is 7 kg. How fast is Matt going as his feet hit the ground? This what I did: P_f = P_i v_f(50kg + 7kg)...

Matt is gliding on his skateboard at 4.00 m/s. He suddenly jumps backward off the skateboard, kicking the skateboard forward at 8.00 m/s. Matt's mass is 50 kg and the skateboard's mass is 7 kg. How fast is Matt going as his feet hit the ground? I have no idea where to begin. Should I first...

i need help on how to start to solve part c in a 3 part question. the question reads "Jerry is stationary on his skateboard at the top of the hill shown in the following diagram. he than rolls from rest down the hill. A) assuming that the hill provides a frictionless surface, determine jerry's...

the question is the topic, but I am sorri i don't have any numbers i can deal with, because we're just supposed to demonstrate that we understand how we solve htese porblems. unfortunately, I don't. could anyone just give me random numbers and tell me how to olve this question? thanks. I am...