Atennis ball is dropped from 1.62 m above the
ground. it rebounds to a height of 0.963 m.
with what velocity does it hit the ground?
the acceleration of gravity is 9.8 m/s. (let
down be negative.)
answer in units of m/s.
ta

-5.63 m/s

Explanation:

Given:

y₀ = 1.62 m

y = 0 m

v₀ = 0 m/s

a = -9.8 m/s²

Find: v

v² = v₀² + 2a (y − y₀)

v² = (0 m/s)² + 2(-9.8 m/s²) (0 m − 1.62 m)

v = -5.63 m/s

.) the observation by semmelweis that more mothers died of childbed fever when their doctors also worked in the morgue

answer: 2×10^-2kg

explanation: density= mass per volume

vol=mass/density

converting to s.i units we have;

3÷1000kg = 0.003

1.5÷100m = 0.15

0.003/0.15 = 0.02kg