The train decelerates uniformly between the yellow and reg lights. Hence, we can apply the equations of motion with uniform acceleration, especially this one:pls solv no 9..... http://www.xtremepapers.com/papers/...nd AS Level/Physics (9702)/9702_w10_qp_11.pdf
http://www.xtremepapers.com/community/members/taci12.40527/
thanks
2*a*x = v^2 - u^2.
the final velocity of the train v = 0. the initial is u. the acceleration is negative, hence we can rewrite it as:
2*a*x = u^2.
the deceleration doesn't change. hence, x is directly proportional to u^2. therefore, a 20% increase in u (making it 1.2u ; 1.2^2 = 1.44) will result in a 44% increase in x. The answer is C.