In: Physics
An object is at x = 0 at t = 0 and moves along the x axis according to the velocity
(a) in this time,the velocity is constant so acceleration is 0.we can show it also using velocity acceleration relationship
v(t) = -10
so acceleration is 0
(b) here velocity is linear with time,so
(c) again
(d) the speed is 0 at t = 6 and t = 18s
so answer is 6,18
(e)the distance travelled will be the area of velocity-time curve which is given
now the velocity is negative from t = 0 to t = 6 ,after that velocity is positive
so till t = 6 seconds,the objects moves in negative x direction(velocity is negative) so total distance covered in this period is area of curve from t = 0 to 6 ,which is equal to 0.5*(10)*(12) = 60meter
after that the velocity is positive,so object start to move into positive x axis and at t = 18 stops,
now the area from t = 6 to t = 18 will be 0.5*(16)*(18) = 144m
so the object first moves 60 meters in negative x direction and then moves 144 meters in positive direction ,so at t = 18s ,it is at a distance of 144-60 = 84 from the origin(x=0) ,so this is the farthest distance
so answer is ,at t= 18,it is farthest.(84 meters)
(f) as solved in pervious part,the position at t = 18 is 84 meters from x= 0,so
position is x = 84 meters
(g) total distance travelled will be the total area of the graph between velocity and time and all area will be add up
so total distance is 60+144 = 204 , so answer is 204 meters