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Motion In Straight Line

Question
CBSEENPH11017189

A particle is moving in a straight line with constant acceleration. It travels a distance of straight alpha in first n seconds, straight beta in next n seconds and y in next n seconds.

Prove that,

α + γ = 2β.

Solution
Consider,
'u' be the initial velocity and 'a' be the acceleration of particle.
Particle travels straight alpha distance in first n seconds, β in next n seconds and gammain next n seconds.
Thus, particle travels α distance in first n seconds, α + β in first 2n seconds and α+β+γ in first 3n seconds.
Therefore, equation of kinematics can be written as

straight alpha equals u n plus 1 half a n to the power of 2 space space space space space end exponent space space space space space space space space space space space space space space space space space space space space space space space space space space space space space... left parenthesis 1 right parenthesis
straight alpha plus straight beta equals 2 u u n plus 1 half straight a left parenthesis 2 straight n right parenthesis squared space space space space space space space space space space space space space space space space space space space... left parenthesis 2 right parenthesis
straight alpha plus straight beta plus straight gamma space equals space 3 u n plus 1 half straight alpha left parenthesis 3 straight n right parenthesis squared space space space space space space space space space space space space space space... left parenthesis 3 right parenthesis
Subtracting (1)  from (2),
         straight beta equals un plus 3 over 2 an squared
For equation (3),
straight alpha plus straight beta plus straight gamma equals 3 open parentheses un plus 3 over 2 an squared close parentheses equals 3 straight beta
That is,
                straight alpha plus straight nu equals 2 straight beta