A block of wood is compressed 2.0 nm when inward forces of magnitude $120 \mathrm{N}$ are applied to it on two opposite sides. (a) Assuming Hooke's law holds, what is the effective spring constant of the block? (b) Assuming Hooke's law still holds, how much is the same block compressed by inward forces of magnitude \(480 \mathrm{N} ?\) (c) How much work is done by the applied forces during the compression of part (b)?

Short Answer

Expert verified
Question: A block of wood compressed by an inward force of 120 N causes a compression of 2.0 nm. Assuming Hooke's Law holds, find the effective spring constant of the block. If the inward forces are increased to 480 N, find the new compression. Calculate the work done by the applied forces during this compression. Answer: The effective spring constant of the block is \(k = 6.0 \times 10^{10}\,\text{N/m}\). The new compression is \(x' = 8.0\,\text{nm}\). The work done by the applied forces during the compression is \(1.92\,\text{J}\).

Step by step solution

01

Find the spring constant

Using the given information, we know that the applied inward force is \(F = 120\,\text{N}\) and the compression is \(x = 2.0\,\text{nm}\) or \(2.0 \times 10^{-9}\,\text{m}\). Hooke's law states that \(F = kx\). We will solve for \(k\): $$k = \frac{F}{x} = \frac{120\,\text{N}}{2.0 \times 10^{-9}\,\text{m}} = 6.0 \times 10^{10}\,\text{N/m}.$$ The effective spring constant of the block is \(k = 6.0 \times 10^{10}\,\text{N/m}\).
02

Calculate the new compression

We are given a new applied inward force, \(F' = 480\,\text{N}\). We need to find the new compression (\(x'\)) using the known spring constant \(k = 6.0 \times 10^{10}\,\text{N/m}\) and Hooke's Law \(F = kx\). Solving for \(x'\): $$x' = \frac{F'}{k} = \frac{480\,\text{N}}{6.0 \times 10^{10}\,\text{N/m}} = 8.0 \times 10^{-9}\,\text{m}.$$ The new compression is \(x' = 8.0\,\text{nm}\).
03

Calculate the work done

To find the work done during the new compression, we will use the formula for work done on a spring: $$W = \frac{1}{2}kx'^2.$$ Substitute the known values of \(k\) and \(x'\): $$W = \frac{1}{2}(6.0 \times 10^{10}\,\text{N/m})(8.0 \times 10^{-9}\,\text{m})^2 = 1.92\,\text{J}.$$ The work done by the applied forces during the compression of part (b) is \(1.92\,\text{J}.\)

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

Yosemite Falls in California is about 740 m high. (a) What average power would it take for a 70 -kg person to hike up to the top of Yosemite Falls in $1.5 \mathrm{h} ?\( (b) The human body is about \)25 \%$ efficient at converting chemical energy to mechanical energy. How much chemical energy is used in this hike? (c) One food Calorie is equal to \(4.186 \times 10^{3} \mathrm{J} .\) How many Calories of food energy would a person use in this hike?
Two springs with spring constants \(k_{1}\) and \(k_{2}\) are connected in parallel. (a) What is the effective spring constant of the combination? (b) If a hanging object attached to the combination is displaced by \(2.0 \mathrm{cm}\) 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 \(83(\mathrm{b}) .]\)
Jorge is going to bungee jump from a bridge that is \(55.0 \mathrm{m}\) over the river below. The bungee cord has an unstretched length of \(27.0 \mathrm{m} .\) To be safe, the bungee cord should stop Jorge's fall when he is at least $2.00 \mathrm{m}\( above the river. If Jorge has a mass of \)75.0 \mathrm{kg},$ what is the minimum spring constant of the bungee cord?
Hilda holds a gardening book of weight \(10 \mathrm{N}\) at a height of $1.0 \mathrm{m}\( above her patio for \)50 \mathrm{s}$. How much work does she do on the book during that 50 s?
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?
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