Question

g An arrow is shot straight up in the air at an initial speed of 15.5 m/s. After how much time is the arrow moving downward at a speed of 5.20 m/s

Answer 1

2.11 seconds

Step-by-step explanation:

We use the kinematic equation for the velocity in a constantly accelerated motion under the acceleration of gravity (g):

`v_f=v_i-g*t\\-5.2 = 15.5 - 9.8\,t\\9.8 \,t= 15.5 + 5.2\\t = 20.7/9.8\\t = 2.11 \,\,sec`