- #1

- 126

- 0

**1. At t=0, a stone is dropped from the top of a cliff above a lake. Another stone is thrown downward 1.6 s later from the same point with an initial speed of 32 m/s. Both stones hit the water at the same instant. Find the height of the cliff.**

**2. d[itex]_{1}[/itex]=[itex]\frac{1}{2}[/itex]gt[itex]_{1}[/itex][itex]^{2}[/itex]; d[itex]_{2}[/itex]=v[itex]_{02}[/itex]t[itex]_{2}[/itex]+[itex]\frac{1}{2}[/itex]gt[itex]_{2}[/itex][itex]^{2}[/itex];d[itex]_{1}[/itex]=d[itex]_{2}[/itex]; t[itex]_{2}[/itex]=t[itex]_{1}[/itex]- 1.6s**

**3. [itex]\frac{1}{2}[/itex]gt[itex]_{1}[/itex][itex]^{2}[/itex]=v[itex]_{02}[/itex]t[itex]_{2}[/itex]+[itex]\frac{1}{2}[/itex]g(t[itex]_{1}[/itex]-1.6s)[itex]^{2}[/itex]. [itex]\frac{1}{2}[/itex](9.81 m/s[itex]^{2}[/itex])t[itex]_{1}[/itex][itex]^{2}[/itex]=(32 m/s)(t[itex]_{1}[/itex]-1.6s)+[itex]\frac{1}{2}[/itex](9.81 m/s[itex]^{2}[/itex])(t[itex]_{1}[/itex]-1.6s)[itex]^{2}[/itex]. Here is where I get stuck in solving the quadratic.**