Request a call back

Join NOW to get access to exclusive study material for best results

JEE Class main Answered

For each natural number k,let Ck denotes the circle with radius k cm and centre at origin.on the circle Ck,a particle moves k cm in the counter clockwise direction.after completing it's motion on Ck, the particle moves onCk+1in the radial direction.the motion of the particle continues in this manner.the particle starts at (1,0).if the particle crosses the positive direction of the x-axis for the first time on the circle Cn,then n is equal to  
Asked by azizrajil03 | 07 Dec, 2018, 06:59: AM
answered-by-expert Expert Answer
Every time the particle moves k cm in a circle Ck which has radius k cm.
Hence angular displacement made by the particle when it travel on each circle is 1 radian ( angle in radian = Arc Length divided by radius)
 
Particle starts from (1,0). It has started from X-axis and travelling first time on circle C1 .
After travelling 1 cm or 1 radian in angular direction it moves radially to Circle  C2 and so on.
To cross positive direction of X-axis, required angular displacement is 2π radians (≈ 6.28 radians ).
Hence after 6 radians particle will move to C7 .
Hence when it travels on C7 it will cross positive direction of x-axis. Hence answer to this question is n = 7
Answered by Thiyagarajan K | 07 Dec, 2018, 11:01: AM

Application Videos

JEE main - Maths
Asked by piyurawriya | 23 Apr, 2024, 02:02: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
JEE main - Maths
Asked by kakumanumanoj282 | 20 Apr, 2024, 06:07: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
JEE main - Maths
Asked by nirmalraulji5 | 18 Apr, 2024, 09:03: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
JEE main - Maths
1
question image
Asked by hadiabbas803 | 17 Apr, 2024, 07:36: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
JEE main - Maths
Asked by veerababukoppisettiveerababu3 | 17 Apr, 2024, 05:49: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
JEE main - Maths
Asked by usakoyalshailesh | 15 Apr, 2024, 09:48: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
JEE main - Maths
Asked by satnamk123 | 15 Apr, 2024, 01:50: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
JEE main - Maths
Asked by sharmalalita847 | 14 Apr, 2024, 09:21: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
JEE main - Maths
Asked by sarthakshukla7275 | 14 Apr, 2024, 01:29: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
JEE main - Maths
Asked by ashwinskrishna2006 | 14 Apr, 2024, 11:58: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
Get Latest Study Material for Academic year 24-25 Click here
×