31.1k views
5 votes
If a ball dropped from a tower reaches the ground after 3.5 seconds, what is the height of the tower?

Given: g = -9.8 meters/second2

User Kinya
by
6.4k points

2 Answers

3 votes
34.3 meters
you multiply how many seconds bt 9.8m
User Ensc
by
7.3k points
2 votes

Answer:


h=60.025m

Step-by-step explanation:

Let's use the "Vertical displacement formula", which gives you the vertical displacement (Height) at any given time t:


\Delta y=y_f-y_i=v_o_yt-(1)/(2) gt^2

Where:


y_f=Final\hspace{3}position=0\hspace{3}(because\hspace{3}has\hspace{3}reached\hspace{3}the\hspace{3}ground\hspace{3}height=0)\\y_i=Initial\hspace{3}position=h\hspace{3}(The\hspace{3}initial\hspace{3}position\hspace{3}represents\hspace{3}the\hspace{3}height\hspace{3}of\hspace{3}the\hspace{3}tower\\v_o_y=Initial\hspace{3}velocity=0\\t=time=3.5s\\g=Standard\hspace{3}gravity \approx-9.8m/s^2

Hence:


-h=-(1)/(2) gt^2\\\\h=(1)/(2) gt^2

Replacing the data provided by the problem:


h=(1)/(2) (9.8)*(3.5^2)=60.025m

User Farshid Palad
by
6.5k points