Chapter 13.9, Problem 33PPS

To determine

To find the value of angle round to nearest tenth from the expression.

Answer to Problem 33PPS

  ${40.8}^{\circ }$

Explanation of Solution

Given: A shot-putter throws the shot with an initial speed of 15 m/s. The expression below represents the time in seconds at which the shot reached its maximum height, x is the angle at which the shot was thrown. The maximum height of the shot was reached in 1.0 second.

  $\frac{\left(15\text{m/s}\right)\left(\sin x\right)}{\left(9.8{\text{m/s}}^2\right)}$

Calculation:

  $\begin{array}{l}1\text{s}=\frac{\left(15\text{m/s}\right)\left(\sin x\right)}{\left(9.8{\text{m/s}}^2\right)}\\ \Rightarrow \sin x=\frac{9.8}{15}\\ \Rightarrow \sin x=0.6533\\ \Rightarrow x={\sin }^{-1}0.6533\\ \Rightarrow x={40.8}^{\circ }\end{array}$

Thus, we found the angle at which the shot was thrown.