CBSE Class 10 Mathematics Circles Assignment Set 01

1 Mark Question

Q1. Find the length of the tangent drawn from a point P.12 cm away from the centre of a circle of radius 5 cm.
Sol Length of tangent PA= √12²-5²= √119cm

Q2. Find the distance of A from the centre of circle.if the length of tangent from A to the circle of radius 9 cm is 12cm
Solution :  In Δ ABO √12²+√9²=15 cm

Q3. Two tangents AB and CD common to two circles which touch each other at C. If point D lies on AB such that tangent CD equal to 4 cm then find the length of AB
Solution :  AB= AD+BD
CD+CD= 2CD= 8cm

Q4 At how many points a secant of the circle intersect the circle
Solution :  2 Points

2 Mark Questions

Q1. Find the length of AP where O is the centre of circle BP is the tangent and OB is the radius BP=8cm, OB=6cm
Solution : In Δ OPB
BP²=OB²+OP²

OP²=8²-6²
OP=√28 =2√7
AP= OA+OP
=OB+2√7
=6+2√7cm

Q2. In the given figure PQ,PR and AB are tangents at points Q,R and S respectively of a circle. If PQ =8 cm .Find the Perimeter of triangle

Solution : AQ=AS
BR=BS
PQ=PR=8cm
Perimeter of Δ APB =AP+AB+PB
= PQ-AQ+AS+BS+PR-BR
=PQ+PR
=8+8=16cm  

Please click the link below to download CBSE Class 10 Mathematics Circles Assignment Set A