Question #f0ab4

1 Answer
Jul 1, 2017

#"The velocity of object at the midpoint is v = "5sqrt(5)" "m/s#

Explanation:

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  • Please examine the chart carefully.The graph is not drawn in scale.
  • The gradient of the velocity-time graph gives the acceleration of the motion.

#"given : "a=5" " m*s^(-2)#

  • let us calculate the slope of the D C E triangle.

#5=(|CE|)/(|DE|)=tan theta#

#CE=15-5=10#

#DE=t-0=t#

#5=10/t#

#t=10/5#

#t=2" seconds"#

-We calculate the area colored in green to find the displacement of the motion.

#"area=displacement"=Delta x=(15+5)/2*t#

#"Substitute t=2"#

#"area=displacement="Delta x=20/cancel(2)*cancel(2)#

#Delta x=20" "meters.(" distance from A to B")#

#"Midpoint of AB is 10 meters."#

  • We can calculate the midpoint velocity of the motion using the fallowing formula.

#v^2=v_i^2+2*a*Delta x#

#v_i=5 m/(s)#

#v=?" (midpoint velocity)"#

#a=5" "m/s^(2)#

#Delta x=10 m#

#v^2=5^2+2*5*10#

#v^2=25+100#

#v^2=125#

#"let us take square root the both sides of equation."#

#sqrt v^2=sqrt(125)#

#v=5sqrt(5)" " m/s#