Resultant Force: Something I am messing up on in calculation - ?

[nukeman]

Resultant Force: Something I am messing up on in calculation - ?

Homework Statement

Hey all,

This is a resultant force word problem. I will just post the my answer and the problems answer. I have no idea why there is a different answer here.

Correct: R^2=1500^2+2300^2 - 2 x 1500 x 2300 Cos(138)
Correct Answer = R = 3559.2 Newton

My answer is WAYYY off, so there is something I am missing here...

By the way, I am using the TI-89 Titanium

Thanks for any help!

Homework Equations

The Attempt at a Solution

 

[berkeman]

Homework Statement

Hey all,

This is a resultant force word problem. I will just post the my answer and the problems answer. I have no idea why there is a different answer here.

Correct: R^2=1500^2+2300^2 - 2 x 1500 x 2300 Cos(138)
Correct Answer = R = 3559.2 Newton

My answer is WAYYY off, so there is something I am missing here...

By the way, I am using the TI-89 Titanium

Thanks for any help!

Homework Equations

The Attempt at a Solution

I get the correct answer just typing it into a cheap ativa scientific calculator.

Can you say what keystrokes you used to get your incorrect answer? I did something like:

cos 138 =

* 2300 =

* 1500 =

* -2 =

+ 2300^2 =

+ 1500^2 =

SQRT =

 

[SammyS]

Maybe it's TOO much calculator for too SMALL a problem.

First question: Is you calculator in 'degree' mode, like berkeman's obviously is?

 

[nukeman]

Thanks both of you.

I figured it out. Sammy, you were basically right, it was too much of a calc for it. Yes, I was in the wrong mode. PAIN in the butt!

So, pulled out my dusty Casio calculator and BOOM! solved :)

Thanks guys

 

[rwisz]

As a scientist, it is important to always double check your calculations and make sure you are using the correct equations and values. In this case, it seems like you may have made a mistake in your calculation or used the wrong values. I would suggest going back and checking your work step by step to identify where the error may have occurred. Additionally, it may be helpful to ask a classmate or teacher for assistance in understanding the problem and finding the correct solution. Don't get discouraged, mistakes happen and it's important to learn from them and keep trying. Good luck!