13 8. A building superintendent twirls a set of keys in a
circle at the end of a cord. If the keys have a centrip-
etal acceleration of 145 m/s2 and the cord has a
length of 0.34 m, what is the tangential speed of the
keys?
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14. I
th

How do hydroponic plants differ from nonhydroponic plants? a.) hydroponic plants can grow in a dryer soil. nonhydroponic plants grow in moist soil. b.) hydroponic plants grow on other plants and are known as air plants. nonhydroponic plants do not grow on other plants. c.) hydroponic plants can only grow in rain forests. nonhydroponic plants cannot grow in rain forests. d.) hydroponic plants are grown without soil. nonhydroponic plants are grown in soil.

Acar drives toward the right over the top of a hill, as shown below. which arrow represents the centripetal acceleration? w x y z

Arunner is training for an upcoming marathon by running around a 100-m-diameter circular track at constant speed. let a coordinate system have its origin at the center of the circle with the x-axis pointing east and the y-axis north. the runner starts at (x, y) = (50 m, 0 m) and runs 2.5 times around the track in a clockwise direction.