A train starts from rest and moves with a constant accelerationof 2.0`m/s^2` for half a minute. The brakes are then applied and the train comes to rest in one minute. Find a. the total distance moved by the train, b. the maximum speed attained by the train and c. the position(s) of the train at half the maximum speed.

Options

A. `(2s.(a_1a_2)/(a_1+a_2))^((1)/(2) ) `
B. ` (2s.(a_1a_2)/(a_1-a_2) )^((1)/(2))`
C. ` ((s)/(2) .(a_1a_2)/(a_1+a_2))^((1)/(2)) `
D. ` ((s)/(2) .(a_1a_2)/(a_1-a_2))^((1)/(2)) `

Answer

A

Explanation

` S = (1)/(2) (t_1+t_2) V_m " "," " S= (1)/(2) ((V_m)/(a_1)+(V_m)/(a_2) ) V_m `
` " "S= (Vm^(2))/(2) ((1)/(a_1)+(1)/(a_2)) ," " V_m =(2s (a_1a_2)/(a_1+a_2)) ^(1//2)`