9) You throw a ball vertically upward from the edge of the roof of the Bisdorf b

Question

9) You throw a ball vertically upward from the edge of the roof of the Bisdorf building with a speed 13.0 m/s. Find a) the position and velocity of the ball 1.00 s after leaving your hand, b) the velocity when the ball is 4.50 m above where you released it, c) the maximum height reached by the ball above the release point and the time at which that height is reached, and d) the acceleration of the ball when it is at its maximum height.

10) You are standing in the Bisdorf building stairwell 5.75 m below your lab partner, who throws your calculator vertically upward to you. You catch the calculator 2.3 s later. a) With what initial velocity was the calculator thrown? b) What was the velocity of the calculator just before you caught it?

Explanation / Answer

9) a) position = 13*1 - 0.5*9.8*1 = 8.1 m

speed = 13-9.8 = 3.2 m/s

b) s = 4.5 m

So v^2 = 13^2 - 2*9.8*4.5

v = 8.988 m/s

c) max height 13^2/2*9.8 = 8.6224 m

time taken = 13/9.8 = 1.326 sec

d) accleration is always constant = g = -9.8 m/s2

10) a) s = -5.75 m

t = 2.3 sec

initial vel = u

-5.75 = u*2.3 - 0.5*9.8*2.3^2

u = 8.77 m/s

vel just before caught = v = 8.77-9.8*2.3 = -13.77 m/s

Related Questions

Navigate

• Browse (All)
• Browse 9
• Subjects

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