StudentShare
Contact Us
Sign In / Sign Up for FREE
Search
Go to advanced search...
Free

Writing a physics report - Essay Example

Cite this document
Summary
If it rolls without slipping, its bottom is momentarily at rest and the distance, velocity, and acceleration of the centre of mass is directly related to the angle of rotation, angular…
Download full paper File format: .doc, available for editing
GRAB THE BEST PAPER96.1% of users find it useful
Writing a physics report
Read Text Preview

Extract of sample "Writing a physics report"

Physics 221L Lab 12 ROTATIONAL MOTION: Rolling Objects 4/15 Purpose of the experiment:To use our cumulative knowledge of Physics to perform an experiment without the benefit of computersTheoryAn object exhibits both rotational motion and transitional motion as it rolls down a plank. If it rolls without slipping, its bottom is momentarily at rest and the distance, velocity, and acceleration of the centre of mass is directly related to the angle of rotation, angular velocity, and angular acceleration of the centre of mass.

The total mechanical energy of the object is the sum of its kinetic energy of its centre of mass, rotational energy about its centre of mass and gravitational potential energy of its centre of mass. (Rotational Motion)Let m – mass of the objectv – Velocity of the object g – Gravitational pull h – Height above the reference ground I – moment of inertia of the object w – Angular velocity of the objectThen:Total mechanical energy = ½ Mv2 + ½ Iw2 + mghWhere: ½ Mv2 – kinetic energy½ Iw2 – rotational energymgh – potential energy Apparatus 1.

Plank 4. Stopwatch2. Object that rolls well3. Meter stick. ProcedureThe object was timed as it rolls a distance of 1 meter starting from rest near the top of the inclined plank and recorded. The height of the inclined plank was also recorded.The plank was turned over and the first procedure repeated, making sure that the object rolls the same distance along the plank and that, the vertical distance is the same. The average time for each side of the plank and the standard deviation of the mean for each side was determined using the formulas belowAverage time = total time/number of trialsStandard mean deviation = √ (variance)Results/Experimental data Data tableTrailTime in seconds (side A)Time in seconds (side B)12.782,2422.422,6332.582.7042.242.2452.712.7562.282.3472.222.64Average2.462.51S.D.M = √Variance0.2110.207Mass of the object = 2.

036Kg Radius of the object = 0.027m Height = 0.08m Data analysis and calculationsFinal velocity “v” (of the centre of mass) in terms of “x” and “t” for the object to roll a distance 1m along the plank in average time t for each side of the plank (experimental velocity).H = 0.08m 0.08mX = 1m 900 1m For rotational velocity down the slope Velocity of centre of mass = 0m/sFor translational motion down the slope Velocity of centre of mass v = u + at Where; v - final velocity u – Initial velocity t – Time taken From the equation s = ut + ½ at2 where; s = displacement a = accelerationSince u = 0 i.e. the object is at rest at the starting point then s = ½ at2 s = 1m 1m = ½ at2 For side A 1 = ½ a (2.462) thus; a = (1 * 2)/2.

462 a = 0.33049m/s2 Velocity VA = at = (0.3349 * 2.46) =0.813m/sFor side B 1 = ½ a (2.512) thus; a = (1 * 2)/2.512 a = 0.3175m/s2 Velocity VB = at = (0.3175 * 2.51) = 0.7968m/s Uncertainty in the final velocity by using the S.D.M. for the time and an estimated uncertainty in distance.Uncertainty in velocity for side A of the plankMean = (2.78+2.42+2.58+2.24+2.71+2.28+2.22)/7 Mean = 2.46sS.D.M = [(2.78-2.462) +(2.42-2.462)+(2.58-2.462)+(2.24-2.462)+(2.71-2.462)+(2.282-2.462)+(2.22-2.46)2]/6 = 0.

211Percentage uncertainty = (0.211/2.46) * 100 = 8.5% Uncertainty in time = x+/- least count Least count 0.01/2 = 0.005 Percentage uncertainty = 0.5%Total uncertainty = (8.5+0.5) = 9% Uncertainty in VA = 0.813±9% 0.73983≤ 0.813 ≥0.88617Uncertainty in velocity for side B of the plankMean = (2.24+2.63+2.70+2.24+2.75+2.34+2.64)/7 Mean = 2.51sS.D.M = [(2.24-2.512)+(2.63-2.512)+(2.70-2.512)+(2.24-2.512)+(2.75-2.512)+(2.34-2.512)+(2.64-2.512)]/6 = 0.207 Percentage uncertainty in time = (0.207/2.51) * 100% = 8.

23%Percentage uncertainty in distance = (0.005/1) * 100% = 0.5%Total uncertainty = (8.23+0.005) = 8.73%Uncertainty in VB = (8.73/100) 0.7968 = ±0.0696 Uncertainty in VB = 0.7968 ± 0.0696Predicting the velocity using conservation of mechanical energy along with the measured vertical distance h. 0.08m θ 1m 900 (Sin 900/1) = (sin θ/0.08) θ = 4.

60 From mgh = ½ Iw2 + ½ Mv2Mass = 2.036KgRadius = 0.027mw = v/r Mgh = ½ I(v/r)2 + ½ mv2 = ½ Iv2/r2 + ½ mv2 Mgh = v2( ½ I/r2 + ½ m) v2 = mgh/(½ I/r2 + ½ m) v = √ [ mgh/(½ I/r2 + ½ m)] But I = ½ mr2 v = √ [ (1/4m + ½ m)] v = √mgh/(3/4 m) v = √[3gh/4] v = √0.5886 v = 0.7672m/sQuestionsDescription of the rolling object. The disk exhibits both rotational motion and transitional motion as it rolls down the plank. Since it rolls without slipping, its bottom is momentarily at rest and the distance, velocity, and acceleration of the centre of mass is directly related to the angle of rotation, angular velocity, and angular acceleration of the centre of mass.

The total mechanical energy of the disk is the sum of its kinetic energy of its centre of mass, rotational energy about its centre of mass and gravitational potential energy of its centre of mass.1. Time for different sides of the plank.The total time for the sides are different, time for when the plank is warped concave up is longer than when the concave is warped down since the disk faces higher friction when the concave is warped up hence taking more time and energy in overcoming friction to reach the end Check the plank for warps.

Make a sketch that shows the warp of the plank. Make sure to label the top and bottom sides. Concave warped up concave warped down2. Relationship between final velocity and predicted if the plank is warped concave up, Concave down as from the data.Predicted velocity is lower on both cases as evidenced by the data i.e. predicted velocity is 0.7672m/s while velocity in the first and second case are 0.7968m/s and 0.813m/s respectively. This is so because predicted velocity does not take care of friction effects and errors in performing the experiment.

ReferenceRotational Motion Retrieved 15th April 2013. www.cliffsnotes.com/study_guide/Rotational- Motiom-of-a-Rigid-Body.topicArticleId-10453,articled-10419.html

Read More
Tags
Cite this document
  • APA
  • MLA
  • CHICAGO
(“Writing a physics report Essay Example | Topics and Well Written Essays - 250 words”, n.d.)
Writing a physics report Essay Example | Topics and Well Written Essays - 250 words. Retrieved from https://studentshare.org/physics/1620919-writing-a-physics-report
(Writing a Physics Report Essay Example | Topics and Well Written Essays - 250 Words)
Writing a Physics Report Essay Example | Topics and Well Written Essays - 250 Words. https://studentshare.org/physics/1620919-writing-a-physics-report.
“Writing a Physics Report Essay Example | Topics and Well Written Essays - 250 Words”, n.d. https://studentshare.org/physics/1620919-writing-a-physics-report.
  • Cited: 0 times

CHECK THESE SAMPLES OF Writing a physics report

Washington's Crossing By David Hackett Fischer

Topic: Book report – Washington Crossing The book “Washington Crossing” by David Hackett Fisher details about the war that occurred in 1776 in America.... The Americans View this American Revolution war through a vaseline coated lens.... In December 1776, in a desperate condition the continental army fought against the massive invasion of British forces who took over New York in an enraged encroachment....
5 Pages (1250 words) Book Report/Review

Paradise Mislaid by Jeffrey Burton Russell

The title of the book is an illusion to John Milton's Paradise Lost, and provides us a history not only of heaven but also of the endless rewriting of its description.... Russell gives us a lot to work with in historical facts, word definitions, and who influenced whom in religion, the church, and philosophies of the day....
7 Pages (1750 words) Book Report/Review

Mysteries of the Mind

This interconnectedness of things is not always apparent.... It is similar to the interconnectedness of neurons in the brain.... The mind can define strange and novel neuropaths that never existed before.... Inventions do not happen out… They are inspired by other things.... There is always some ‘learning' that exhibits through inventions....
4 Pages (1000 words) Book Report/Review

Biopsychosocial in Social Work

hellip; Consent from the guardian and school authorities have been obtained prior to utilizing Harry's case in this report.... arry was also evaluated to be faring poorly in reading, writing, and arithmetic.... This essay focuses on children with Attention Deficit Hyperactivity Disorder, such as Harry in the case discussed, has special considerations in caring for them....
11 Pages (2750 words) Book Report/Review

What Does the Theory of Planned Behaviour Tell about Using a Cell Phone while Driving

The study “What Does the Theory of Planned Behaviour Tell about Using a Cell Phone while Driving?... rdquo; proved that most respondents were unanimous in the opinion that using a mobile phone to send text messages is dangerous.... While some of those who broke the rule earlier were ready to break it again....
18 Pages (4500 words) Lab Report

Half of a Yellow Sun by Chimamanda Ngozi Adichie

This book review "Half of a Yellow Sun by Chimamanda Ngozi Adichie" focuses on a novel which was written by Chimamanda Ngozi Adichie, who uses the story of Ogdenibo, Olanna, Kainene, Ugwu and Richard Churchill to present the story of turbulent Nigeria during the Biafra War.... nbsp;… Half of a Yellow Sun is an invaluable novel that covers all the details of the Biafra War....
6 Pages (1500 words) Book Report/Review

Skull Identification - Index and the Non-Index Traits

In the identification, the names of the specimens C, D, E, F, G, H and B are given in the chart and any reference made in this report should be counterchecked in the chart.... This paper "Skull Identification - Index and the Non-Index Traits" focuses on skull identification which entails the observation of the index traits and the non-index (physical) traits....
5 Pages (1250 words) Lab Report

The Goal The Process of Ongoing Improvement

The book "The Goal" is about getting things right on track in order to get the best results.... The author, in the beginning, emphasizes the fact that we alone have the power to get the things done.... In addition, our technical knowledge has no part to play in it.... hellip; The narrator of this essay aims to tell that people need to understand what is the factor around which the whole universe operates and how they can make things better for themselves....
7 Pages (1750 words) Book Report/Review
sponsored ads
We use cookies to create the best experience for you. Keep on browsing if you are OK with that, or find out how to manage cookies.
Contact Us