## kbarnes7 one year ago a machine can toss a golf ball a distance of 120 m on a level playing field when the machine is set to an angle of 30 degrees. How far can the machine toss the ball when it is set to an angle of 45 degrees.

1. shubham.bagrecha

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2. kbarnes7

ok so where do i go from there

3. shubham.bagrecha

$R=\frac{u^2 \sin(2 \theta)}{g}$ $\theta = 30 degrees$R=120m $120=\frac{u^2 \sin(2 *30)}{10}$ find u.

4. shubham.bagrecha

then find R for 45 degrees with this u.

5. kbarnes7

ok, so is it 170 m, 98 m , 140 m , 85 m or 150 m? trying to check my answer

6. shubham.bagrecha

what u you got?

7. kbarnes7

98 m?

8. shubham.bagrecha

$u^2 = \frac{120*10}{\sin 60}$ $u^2 = 800\sqrt{3}$ now theta = 45 $R=\frac{u^2 \sin(2*45)}{10}$ substitute value of u^2. $R=\frac{800 \sqrt{3} \sin(2*45)}{10}$

9. shubham.bagrecha

$R=80\sqrt{3}$

10. kbarnes7

man i missed that up, so with sig figs.... 140 m?