Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Mensuration: 3D

Question:

A chord of length 42 cm is drawn in a circle having diameter 58 cm. What is the minimum distance of other parallel chord of length 40 cm in the same circle from 42 cm long chord?

Options:

4 cm

1 cm

3 cm

2 cm

Correct Answer:

1 cm

Explanation:

We know that,

H2 = B2 + P2

We have,

The diameter of the circle = 58 cm

The length of one chord = 42 cm

The length of another chord = 40 cm

AB and PQ are two chords, and O is the center of the circle.

M is the midpoint of AB and N is the midpoint of PQ

OB = OQ = 29 cm [radius of the circle]

AB = 42 cm and OB = 29

Then,

AM = MB = \(\frac{42}{2}\) = 21

In ΔMOB

(OB)= (OM)2 + (MB)2

= (29)2 = (OM)2 + (21)2

= 841 = (OM)2 + 441

= OM = 20 cm

Now,

PQ = 40 cm and OB = 29

NQ = PN = \(\frac{40}{2}\) = 20

In ΔONQ

(OQ)2 = (ON)2 + (NQ)2  = (29)2 = (ON)2 + (20)2

= 841 = (ON)2 + 400

= ON = 21 cm

So according to the question. = 21 – 20 = 1