How Do I Solve This Projectile Motion Equation?

[chevymechanic]

Homework Statement

Here's the equation I have:

0-730=V₀sin(-37.0)(5.00)-(1/2)(9.8m/s²)(5.00)²

Homework Equations

The Attempt at a Solution

I know the answer is 202 m/s. I just can't figure out how to get there. I've reduced it to:

-730=(V₀sin(-37.0))(5.00)-122.5

The sine is throwing me a curve ball. It's just an example equation out of the book so that I can solve the real one in my homework. I'm sure it's something simple I'm missing.

 

[gneill]

sin(-37.0°) has a real valued result. What is it?

 

[davo789]

Can I ask why is the sin causing you a problem?

 

[vela]

Why is it confusing you? sin -37.0° is just a number.

 

[daveb]

If you're using a claulator, make sure your trig functions use degrees rather than radians - that might be the trick

 

[chevymechanic]

sin(-37.0)= -.601815

But when I try to solve -730=V₀(-.601815)(5.00)-122.5 I get -730=V₀-125.509. I just don't see how to go from that to the answer V₀=202 m/s

 

[gneill]

sin(-37.0)= -.601815

But when I try to solve -730=V₀(-.601815)(5.00)-122.5 I get -730=V₀-125.509. I just don't see how to go from that to the answer V₀=202 m/s

V_o multiplies (-.601815)(5.00). Don't add (-.601815)(5.00) to -122.5!

 

[chevymechanic]

Haha! Success! I've figured it out. I knew it had to be something simple. I just needed someone to clear things up for me. Thanks a million!