Changes

Jump to navigation Jump to search
m
Line 1: Line 1: −
<div style="width:150px;border:none; border-radius:10px;box-shadow: 5px 5px 5px #888888; background:#ffffff; vertical-align:top; text-align:center; padding:5px;">
+
Investigating the diameter is the longest chord of a circle.
''[http://karnatakaeducation.org.in/KOER/index.php/೧೦ನೇ_ತರಗತಿಯ_ವೃತ್ತ_-_ಸ್ಪರ್ಶಕದ_ಗುಣಲಕ್ಷಣಗಳು ಕನ್ನಡದಲ್ಲಿ ನೋಡಿ]''</div>
      +
===Objectives===
 +
To understand longest chord passes through the centre and it is the diameter
 +
===Estimated Time===
 +
30 minutes
   −
<!-- This portal was created using subst:box portal skeleton  -->
+
===Prerequisites/Instructions, prior preparations, if any===
<!--        BANNER ACROSS TOP OF PAGE        -->
+
Prior knowledge of point, lines, angles, polygons
{| id="mp-topbanner" style="width:100%;font-size:100%;border-collapse:separate;border-spacing:20px;"
  −
|-
  −
|style="width:10%; border:none; border-radius:5px;box-shadow: 10px 10px 10px #888888; background:#f9f9ff; vertical-align:middle; text-align:center; "|
  −
[http://karnatakaeducation.org.in/KOER/en/index.php/Mathematics:_History The Story of Mathematics]
  −
|style=" width:10%; border:none; border-radius:5px;box-shadow: 10px 10px 10px #888888; background:#f9f9ff; vertical-align:middle; text-align:center; "|[http://karnatakaeducation.org.in/KOER/en/index.php/Mathematics:_Philosophy Philosophy of Mathematics]
  −
|style=" width:10%; border:none; border-radius:5px;box-shadow: 10px 10px 10px #888888; background:#f9f9ff; vertical-align:middle; text-align:center; "|
  −
[http://karnatakaeducation.org.in/KOER/en/index.php/Mathematics:_Pedagogy Teaching of Mathematics]
  −
|style=" width:10%; border:none; border-radius:5px;box-shadow: 10px 10px 10px #888888; background:#f9f9ff; vertical-align:middle; text-align:center; "|
  −
[http://karnatakaeducation.org.in/KOER/en/index.php/Maths:_Curriculum_and_Syllabus Curriculum and Syllabus]
  −
|style=" width:10%; border:none; border-radius:5px;box-shadow: 10px 10px 10px #888888; background:#f9f9ff; vertical-align:middle; text-align:center; "|
  −
[http://karnatakaeducation.org.in/KOER/en/index.php/Mathematics:_Topics Topics in School Mathematics]
  −
|style=" width:10%; border:none; border-radius:5px;box-shadow: 10px 10px 10px #888888; background:#f9f9ff; vertical-align:middle; text-align:center; "|
  −
[http://karnatakaeducation.org.in/KOER/en/index.php/Text_Books#Mathematics_-_Textbooks Textbooks]
  −
|style=" width:10%; border:none; border-radius:5px;box-shadow: 10px 10px 10px #888888; background:#f9f9ff; vertical-align:middle; text-align:center; "|
  −
[http://karnatakaeducation.org.in/KOER/en/index.php/Maths:_Question_Papers Question Bank]
  −
|}
  −
While creating a resource page, please click here for a resource creation [http://karnatakaeducation.org.in/KOER/en/index.php/Resource_Creation_Checklist '''checklist'''].
     −
= Concept Map =
+
===Materials/ Resources needed===
__FORCETOC__
+
* Digital : Computer, geogebra application, projector.
<mm>[[circles_and_lines.mm|flash]]</mm>
+
* Non digital : Worksheet and pencil, compass, strings
 +
* Geogebra files :  [https://ggbm.at/c4eg7q2u Diameter is longest chord.ggb]
 +
{{Geogebra|c4eg7q2u}}
   −
= Textbook =
+
===Process (How to do the activity)===
To add textbook links, please follow these instructions to:
+
Use the geogebra file to show how diameter is the longest chord.
([{{fullurl:{{FULLPAGENAME}}/textbook|action=edit}} Click to create the subpage])
     −
=Additional Information=
+
Move the points on the circle to show the changes in the triangle.
==Useful websites==
  −
#[http://www.regentsprep.org/Regents/math/geometry/GP14/PracCircleSegments.htm www.regentsprep.com] conatins good objective problems on chords and secants <br>
  −
#[http://www.mathwarehouse.com/geometry/circle/tangents-secants-arcs-angles.php www.mathwarehouse.com] contains good content on circles for different classes<br>
  −
#[http://staff.argyll.epsb.ca/jreed/math20p/circles/tangent.htm staff.argyll]  contains good simulations
     −
==Reference Books==
+
What is the condition with respect to sides for formation of a triangle. Sum of two sides is larger than the third side.
   −
= Teaching Outlines =
+
Compare the chord length with sum of two radii. When is the triangle reduced to a line segment.
Chord and its related theorems
  −
==Concept #1 Chord==
  −
===Learning objectives===
  −
# Meaning of circle and chord.
  −
# Method to measure the perpendicular distance of the chord from the centre of the circle.
  −
# Properties of chord.
  −
# Able to relate chord properties to find unknown measures in a circle.
  −
# Apply chord properties for proof of further theorems in circles.
  −
# Understand the meaning of congruent chords.
  −
===Notes for teachers===
  −
# A chord is a straight line joining 2 points on the circumference of a circle.
  −
# Chords within a circle can be related in many ways.
  −
# The theorems that involve chords of a circle are :
  −
* Perpendicular bisector of a chord passes through the center of a circle.
  −
* Congruent chords are equidistant from the center of a circle.
  −
* If two chords in a circle are congruent, then their intercepted arcs are congruent.
  −
* If two chords in a circle are congruent, then they determine two central angles that are congruent.
     −
===Activities===
+
What can you conclude about the chord? When is it the largest?
#Activity No 1 - [[Circles_and_lines_activity_1|Theorem 1: Perpendicular bisector of a chord passes through the center of a circle]]
  −
#Activity No 2 - [[Circles_and_lines_activity_2|Theorem 2.Congruent chords are equidistant from the center of a circle]]
     −
==Concept #2.Secant and Tangent==
+
[[Category:Circles]]
===Learning objectives===
  −
# The secant is a line passing through a circle touching it at any two points on the circumference.
  −
# A tangent is a line toucing the circle at only one point on the circumference.
  −
===Notes for teachers===
  −
===Activities===
  −
#Activity #1 - [[Circles_and_lines_activity_3|Understanding secant and tangent using Geogebra]]
  −
 
  −
==Concept #3 Construction of tangents==
  −
===Learning objectives===
  −
# The students should know that tangent is a straight line touching the circle at one and only point.
  −
# They should understand that a tangent is perpendicular to the radius of the circle.
  −
# The construction protocol of a tangent.
  −
# Constructing a tangent to a point on the circle.
  −
# Constructing tangents to a circle from external point at a given distance.
  −
# A tangent that is common to two circles is called a common tangent.
  −
# A common tangent with both centres on the same side of the tangent is called a direct common tangent.
  −
# A common tangent with both centres on either side of the tangent is called a transverse common tangent.
  −
 
  −
===Notes for teachers===
  −
===Activities===
  −
#Activity #1 - [[Circles_and_lines_activity_4|Construction of Direct common tangent]]
  −
#Activity #2 - [[Circles_and_lines_activity_5|Construction of Transverse common tangent]]
  −
 
  −
==Concept #4 Cyclic quadrilateral==
  −
===Learning objectives===
  −
# A quadrilateral ABCD is called cyclic if all four vertices of it lie on a circle.
  −
# In a cyclic quadrilateral the sum of opposite interior angles is 180 degrees.
  −
# If the sum of a pair of opposite angles of a quadrilateral is 180, the quadrilateral is cyclic.
  −
# In a cyclic quadrilateral the exterior angle is equal to interior opposite angle
  −
===Notes for teachers===
  −
===Activities===
  −
#Activity #1 - [[Circles_and_lines_activity_6|Cyclic quadrilateral]]
  −
#Activity #2 - [[Circles_and_lines_activity_7|Properties of cyclic quadrilateral]]
  −
 
  −
 
  −
= Hints for difficult problems =
  −
#Tangents AP and AQ are drawn to circle with centre O, from an external point A. Prove that  ∠PAQ=2.∠ OPQ
  −
Please click [http://karnatakaeducation.org.in/KOER/en/index.php/Class10_circles_tangents#Problem_1 here] for solution.
  −
 
  −
[[Class10_circles_tangents|here]]
  −
 
  −
= Project Ideas =
  −
 
  −
= Math Fun =
  −
 
  −
'''Usage'''
  −
 
  −
Create a new page and type <nowiki>{{subst:Math-Content}}</nowiki> to use this template
 
3,664

edits

Navigation menu