Question
A body moves in a straight line,with initial
velocity and uniform acceleration.find how
far it travels in 12sec.,given that it travels
246m in the first 6 sec.,and 69m in the last
3sec.find the initial velocity.
Please show step
velocity and uniform acceleration.find how
far it travels in 12sec.,given that it travels
246m in the first 6 sec.,and 69m in the last
3sec.find the initial velocity.
Please show step
Answers
s(t) = s<sub><sub>0</sub></sub> + v<sub><sub>0</sub></sub>t + a/2 t^2
so,
s<sub><sub>0</sub></sub> + 6v<sub><sub>0</sub></sub> + 18a = 246
s<sub><sub>0</sub></sub> + 9v<sub><sub>0</sub></sub> + 81/2 a = 246+69
Solve for v<sub><sub>0</sub></sub>
so,
s<sub><sub>0</sub></sub> + 6v<sub><sub>0</sub></sub> + 18a = 246
s<sub><sub>0</sub></sub> + 9v<sub><sub>0</sub></sub> + 81/2 a = 246+69
Solve for v<sub><sub>0</sub></sub>
6 V0 + 18 a = 246
V0 + 9 a = V1
3 V1 + 4.5 a = 69
subs ... 3 V0 + 27 a + 4.5 a = 69
... times 2 ... 6 V0 + 63 a = 138
subtract to eliminate V0
... 45 a = -108
... a = -2.4
substitute back to find V0
V0 + 9 a = V1
3 V1 + 4.5 a = 69
subs ... 3 V0 + 27 a + 4.5 a = 69
... times 2 ... 6 V0 + 63 a = 138
subtract to eliminate V0
... 45 a = -108
... a = -2.4
substitute back to find V0