Class Exercise 3 – Circle

Circles Review – Fundamentals of CirclesFormulas for Circle,  Congruent CirclesTangent to a circlePolygon inscribed in a Circle  , Circle inscribed in a circleConcentric Circles

Class Questions –  Exercise 1         Exercise 2      Exercise 3        Exercise 4      Exercise 5

Practice QuestionsSolutions

—————————————————————

Q.5   In the following figure, the radius of the circle is 9.

cir4

Quantity A                                                                    Quantity B

                        72 π                                                                   area of shaded region

        A.  If Quantity A is greater

       B.  If Quantity B is greater

       C.  If Quantity A and Quantity B are equal

       D.  The relationship cannot be determined from given information

Solution:

cir-18

Q.6           If the length of a thread is 258 and it is being  tied around a circular pole making 20 turns. What could be the nearest possible value of the diameter of a pole from the following?

     A.  12.9
     B.  12.8
     C.  12.3
     D.  12.0
    E.   11π

 Solution;

Number of turns = 20
Length of thread = 258
So,
For 20 of turns,      Length of thread = 258
One turn around pole = 1 x  258 / 20
                                                  = 12.9
One turn of thread around the pole = Diameter of pole,
                 i.e.  Diameter of pole = 12.9,

    The Correct answer is A.

                                                                                                

error: