Question

You run due east at a constant speed of 3.00 m/s for a distance of 120.0 m and then continue running east at a constant speed of 5.00 m/s for another 120.0 m. For the total 240.0-m run, is your average velocity 4.00 m/s, greater than 4.00 m/s, or less than 4.00 m/s? Explain.

Answer 1

Answer:

Explanation:

Given

Speed while running towards east is $v_1=3\ m/s$

Distance traveled in east direction $x_1=120\ m$

For Another interval you  run with velocity

$v_2=5\ m/s$

$x_2=240\ m$

Total displacement$=x_1+x_2$

$=120+120=240\ m$

Time for first interval

$t_1=\frac{x_1}{v_1}=\frac{120}{3}$

$t_1=\frac{120}{3}=40\ s$

Time for second interval

$t_2=\frac{x_2}{v_2}=\frac{120}{5}=24\ s$

total time $t=t_1+t_2$

$t=40+24=64\ s$

average velocity $v_{avg}=\frac{x_1+x_2}{t}$

$v_{avg}=\frac{240}{64}=3.75\ m/s$

Therefore average velocity is less than $4 m/s$