A 69.0 -kg short-track ice skater is racing at a speed of $11.0 \mathrm{m} / \mathrm{s}$ when he falls down and slides across the ice into a padded wall that brings him to rest. Assuming that he doesn't lose any speed during the fall or while sliding across the ice, how much work is done by the wall while stopping the ice skater?

Short Answer

Expert verified
Answer: The work done by the padded wall to stop the ice skater is 4174.5 Joules.

Step by step solution

01

Find the initial kinetic energy of the skater

First, we need to determine the initial kinetic energy of the skater before hitting the wall. The formula for kinetic energy is given as: KE = \(\frac{1}{2}mv^{2}\) where m is the mass and v is the velocity of the object. We can plug the given values into the formula: m = 69.0 kg (mass of skater) v = 11.0 m/s (velocity of skater)
02

Calculate the initial kinetic energy

Now we can calculate the initial kinetic energy: KE = \(\frac{1}{2}(69.0 \mathrm{kg})(11.0 \mathrm{m/s})^{2}\)
03

Perform the calculation

Calculating the initial kinetic energy, we get: KE = \(\frac{1}{2}(69.0)(121.0) = 4174.5 \mathrm{J}\) (Joules)
04

Determine the final kinetic energy

Since the skater comes to a complete stop after hitting the wall, his final kinetic energy is 0J.
05

Apply the work-energy theorem

Now that we have the initial and final kinetic energies, we can use the work-energy theorem to determine the work done by the wall: Work = Change in Kinetic Energy = Final KE - Initial KE Work = \(0 \mathrm{J} - 4174.5 \mathrm{J}\)
06

Calculate the work done

Now we can calculate the work done by the wall: Work = -4174.5 J The negative sign indicates that the work done is in the opposite direction of the initial movement of the skater. So, the work done by the padded wall to stop the ice skater is 4174.5 Joules.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Two springs with spring constants \(k_{1}\) and \(k_{2}\) are connected in series. (a) What is the effective spring constant of the combination? (b) If a hanging object attached to the combination is displaced by \(4.0 \mathrm{cm}\) from the relaxed position, what is the potential energy stored in the spring for \(k_{1}=5.0 \mathrm{N} / \mathrm{cm}\) and $k_{2}=3.0 \mathrm{N} / \mathrm{cm} ?$ [See Problem \(83(\mathrm{a}) .]\)
A 75.0 -kg skier starts from rest and slides down a 32.0 -m frictionless slope that is inclined at an angle of \(15.0^{\circ}\) with the horizontal. Ignore air resistance. (a) Calculate the work done by gravity on the skier and the work done by the normal force on the skier. (b) If the slope is not frictionless so that the skier has a final velocity of \(10.0 \mathrm{m} / \mathrm{s},\) calculate the work done by gravity, the work done by the normal force, the work done by friction, the force of friction (assuming it is constant), and the coefficient of kinetic friction.
Rachel is on the roof of a building, \(h\) meters above ground. She throws a heavy ball into the air with a speed \(v,\) at an angle \(\theta\) with respect to the horizontal. Ignore air resistance. (a) Find the speed of the ball when it hits the ground in terms of \(h, v, \theta,\) and \(g .\) (b) For what value(s) of \(\theta\) is the speed of the ball greatest when it hits the ground?
The maximum speed of a child on a swing is \(4.9 \mathrm{m} / \mathrm{s}\) The child's height above the ground is \(0.70 \mathrm{m}\) at the lowest point in his motion. How high above the ground is he at his highest point?
A record company executive is on his way to a TV interview and is carrying a promotional CD in his briefcase. The mass of the briefcase and its contents is \(5.00 \mathrm{kg}\) The executive realizes that he is going to be late. Starting from rest, he starts to run, reaching a speed of $2.50 \mathrm{m} / \mathrm{s} .$ What is the work done by the executive on the briefcase during this time? Ignore air resistance.
See all solutions

Recommended explanations on Physics Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free