{"id":1993,"date":"2023-10-02T08:08:26","date_gmt":"2023-10-02T08:08:26","guid":{"rendered":"http:\/\/localhost\/ecole9ja\/?p=1993"},"modified":"2023-10-02T08:08:49","modified_gmt":"2023-10-02T08:08:49","slug":"week-10-ss1-first-term-physics-notes","status":"publish","type":"post","link":"https:\/\/ecolebooks.com\/nigeria\/posts\/week-10-ss1-first-term-physics-notes\/","title":{"rendered":"Week 10 &#8211; SS1 First Term Physics Notes"},"content":{"rendered":"<p><strong>WEEK TEN<\/strong><br \/>\n\t\t<strong>TOPIC: VISCOSITY<br \/>\n<\/strong><strong>CONTENT<br \/>\n<\/strong><\/p>\n<ul>\n<li><strong>Meaning of Viscosity<br \/>\n<\/strong><\/li>\n<li><strong>Experiment to Determine the Terminal Velocity of a Steel Ball Falling  in a Fluid<br \/>\n<\/strong><\/li>\n<li><strong>Factors Affecting Viscosity<br \/>\n<\/strong><\/li>\n<li><strong>Effect of Viscosity<br \/>\n<\/strong><\/li>\n<li><strong>Application of Viscosity<br \/>\n<\/strong><\/li>\n<\/ul>\n<p>\u00a0<strong>MEANING OF VISCOSITY<br \/>\n<\/strong>Viscosity is the internal friction which exists between layers of the molecules of a fluid (liquid or gas) in motion. The viscosity of a fluid can also be defined as the measure of how resistive the fluid is to flow. It is a vector quantity &amp; measured in pascal-seconds(pa.s). It can be defined mathematically as the ratio of the shearing stress to the velocity gradient in a fluid<br \/>\n\t\t\t\t\t\tViscosity (\u014b) =           Force<br \/>\n                   Area x Velocity gradient  \u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026.1.<br \/>\nVelocity gradient = velocity<br \/>\n\t\t                                Length   \u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u20262<\/p>\n<p>\t\t\t<img decoding=\"async\" src=\"https:\/\/ecolebooks.com\/nigeria\/wp-content\/uploads\/9jalessonsimages\/100223_0808_Week10SS1F1.png\" alt=\"\"\/><br \/>\n\t\tW = U +  V<br \/>\nW \u2013 U- V = 0        \u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u20263.<br \/>\nV = W \u2013 U (apparent or effective weight) where V-viscous force, W- weight, U- upthrust<br \/>\nNB : Substances with low viscosity include water, kerosene, petrol, ethanol. Those with high viscosity are glue, syrup, grease, glycerine etc<\/p>\n<p>\u00a0<strong>Experiment to Determine the Terminal Velocity of a Steel Ball Falling Through a Fluid<br \/>\n<\/strong><strong>Aim<\/strong>: To determine the terminal velocity of a steel ball falling in through a jar of glycerin<br \/>\n<strong>Apparatus<\/strong>: steel ball, cylindrical calibrated jar, glycerine<br \/>\n<strong>Diagram<\/strong>:                                                                  <\/p>\n<p>\t\t\t<img decoding=\"async\" src=\"https:\/\/ecolebooks.com\/nigeria\/wp-content\/uploads\/9jalessonsimages\/100223_0808_Week10SS1F2.png\" alt=\"\"\/><br \/>\n\t\t<strong>Procedure<\/strong>:  Set-up the apparatus as shown above &amp; gently drop the steel ball in the jar of glycerin<br \/>\n<strong>Observation<\/strong>: It will be observed that the ball is accelerating in the liquid. Also the time taken for the ball to move from A-B will be different from B-C and so on. A time will be reached when the ball will be moving at a constant speed or velocity. It is that point that terminal velocity is experience.<br \/>\nGraph : <\/p>\n<p>\t\t\t<img decoding=\"async\" src=\"https:\/\/ecolebooks.com\/nigeria\/wp-content\/uploads\/9jalessonsimages\/100223_0808_Week10SS1F3.png\" alt=\"\"\/><br \/>\n\t\t<strong>Conclusion<\/strong>: Terminal velocity is attained when W = V + U. At a point when the ball is moving at a constant speed through the glycerine.<strong><br \/>\n\t\t\t<\/strong><strong>Precaution<\/strong>: 1. The steel ball should be dropped gently on the liquid 2. Experiment should be done under constant temperature 3. Avoid error of measurement when taken the reading.<br \/>\nNB: <strong>Terminal velocity<\/strong> is the maximum velocity of an object when the viscous force due to motion of the object equals the apparent (effective) weight of the object in the fluid where there is no longer net force on the object.<br \/>\n<strong>Drag force<\/strong> is the force that keeps the object continuously moving after the terminal velocity has been attained.<br \/>\n<strong>Stokes&#8217; Law<\/strong> state that at the terminal velocity, the upward frictional force (F) = 6\u03a0 \u014brV<br \/>\nWhere F- Frictional\/Drag force, \u014b- viscosity, r- radius of sphere, V<sub>t<\/sub>&#8211;  Terminal velocity<\/p>\n<p>\u00a0<strong>EVALUATION<br \/>\n<\/strong><\/p>\n<ol>\n<li>\n<div>Derive the dimension of viscosity.\n<\/div>\n<p>2.   \u00a0\u00a0\u00a0\u00a0Describe an experiment to determine the terminal velocity of a steel ball falling in a fluid.\n<\/li>\n<\/ol>\n<p>\u00a0<strong>Factors Affecting Viscosity<br \/>\n<\/strong><\/p>\n<ol>\n<li>Viscosity varies with material (viscosity is a property of material)\n<\/li>\n<li>The viscosity of simple liquids (a) decreases with increasing temperature (b) increases under very high pressure\n<\/li>\n<li>The viscosity of gases (a) increases with increasing temperature (b) is independent of pressure &amp; density\n<\/li>\n<\/ol>\n<p>\u00a0<strong>Effect of Viscosity<\/strong><\/p>\n<ol>\n<li>Viscosity is responsible for different rate of fluid flow.\n<\/li>\n<li>\n<div>Viscosity affect motion of body in fluid.\n<\/div>\n<p>\u00a0<strong>Application of Viscosity<\/strong>\n\t\t\t\t<\/li>\n<li>It is use as a lubricant.\n<\/li>\n<li>The knowledge of viscous drag\/drag force is applied in the design of ship &amp; aircraft.\n<\/li>\n<li>\n<div>Use to estimate the enlarge size of particles.\n<\/div>\n<p>\u00a0<strong>EVALUATION<br \/>\n<\/strong><\/li>\n<li>State two effects of viscosity.\n<\/li>\n<li>\n<div>State two applications of viscosity.\n<\/div>\n<p>\u00a0<strong>GENERAL EVALUATION<br \/>\n<\/strong><\/li>\n<li><strong>  Wh<\/strong>at is viscosity?\n<\/li>\n<li>  What is terminal velocity?\n<\/li>\n<li>  State two(2) substances with high viscosity.\n<\/li>\n<li>  State Stoke&#8217;s law.\n<\/li>\n<li>\n<div>  What is a viscostatic substance?\n<\/div>\n<p>\u00a0<strong>READING ASSIGNMENT<br \/>\n<\/strong>New school physics by M.W.Anyakoha,Phd.Pg  105 \u2013 107<\/p>\n<p>\u00a0<strong>WEEKEND ASSIGNMENT<br \/>\n<\/strong><\/p>\n<ol>\n<li>Viscosity opposes motion of an object in (a) solid (b) liquid only(c) gas only (d) liquid &amp; gas\n<\/li>\n<li>The SI unit of velocity gradient is (a) m\/s (b) s<sup>-1<\/sup> (c)  m\/s<sup>2<\/sup> (d) ms\n<\/li>\n<li>Terminal velocity is attained when (a) w + v = u (b) w = v \u2013 u (c) w + u = v (d) w = v + u\n<\/li>\n<li>The following are vector quantities except (a) friction (b) viscosity (c) upthrust (d) pressure\n<\/li>\n<li>Friction and viscosity are similar but not the same.  True\/False\n<\/li>\n<\/ol>\n<p>\u00a0<strong>THEORY<br \/>\n<\/strong><\/p>\n<ol>\n<li>Explain viscosity.\n<\/li>\n<li>Describe an experiment to determine the terminal velocity of a steel ball falling in a fluid.\n<\/li>\n<\/ol>\n<p>NB: A liquid is said to be <strong>VISCOSTATIC <\/strong>if its viscosity does not change (appreciably) with change in temperature.\n<\/li>\n<\/ol>\n","protected":false},"excerpt":{"rendered":"<p>WEEK TEN TOPIC: VISCOSITY CONTENT Meaning of Viscosity Experiment to Determine the Terminal Velocity of&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1,176],"tags":[],"class_list":["post-1993","post","type-post","status-publish","format-standard","hentry","category-posts","category-first-term-ss1-physics"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/posts\/1993","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/comments?post=1993"}],"version-history":[{"count":1,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/posts\/1993\/revisions"}],"predecessor-version":[{"id":1994,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/posts\/1993\/revisions\/1994"}],"wp:attachment":[{"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/media?parent=1993"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/categories?post=1993"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/tags?post=1993"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}