Two runners cover the same distance in a straight line. Runner A runs at constan

Question

Two runners cover the same distance in a straight line. Runner A runs at constant velocity. Runner B starts from rest, maintains a constant acceleration a, and covers the distance in the same time as runner A. (a) Compared to runner A's constant velocity, runner B's final velocity is [1] smaller [2] equal [3] larger (b) Compared to runner A's constant velocity, runner B's average velocity is [1] smaller [2] equal [3] larger Both runners cover the distance of 100 m in a time of 10 seconds. (c) What is the constant velocity of runner A? [1] 0 [2] 5 m/s [3] 10 m/s [4] 20 m/s [5] 100 m/s (d) What is the average velocity of runner B? [1] 0 [2] 5 m/s [3] 10 m/s [4] 20 m/s [5] 100 m/s (e) What is the final velocity of runner B? [1] 0 [2] 5 m/s [3] 10 m/s [4] 20 m/s [5] 100 m/s (f) What is the acceleration of runner B. [1] -2 m/s2 [2] 0 [3] 1 m/s2 [4] 2 m/s2 [5] 10 m/s2 Please be sure your answers to (c)-(e) are consistent with (a) and (b).

Explanation / Answer

a) Compared to runner A's constant velocity, runner B's final velocity is larger

b) Compared to runner A's constant velocity, runner B's average velocity is smaller

c) constant velocity of runner A is v=s/t = 10 m/s

d) the average velocity of runner B is

   acceleration a = 2s / t^2 = 200/100 = 2 m/s^2

therefore final velocity v = at = 2* 10 = 20 m/s

average velocity is 20/2 = 10 m/s

e) the final velocity of B is 20 m/s

f) acceleration of runner B is 2 m/s^2

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.