Resistive force question using T (tension)

[Siliconwombat]

Homework Statement

A horse is pulling a canal boat using a rope at 12° to the direction of motion of the boat.
The tension in the rope is 1150 N.
(a) The canal boat is moving at a steady speed. Calculate the resistive force opposing
the boat’s forward motion.

Homework Equations

Answer sheet gives equation as:
T = T cos θ

The Attempt at a Solution

Solution is given as:

= 1150 N x cos 12°
= 1125 N
Therefore resistive forces = 1125 N

However I've tried two different scientific calculators. The windows version comes out at 13800 and googles version comes out at 970.43

Am I using these tools incorrectly or are they flawed with calculations of this type?

Many thanks, its driving me crazy!

 

[ap123]

Hi Siliconwombat

Your 970 answer : you've put in 12 rad instead of 12°
Your 13800 answer : you've put in 12 instead of cos(12°) !

All it takes is a bit more care :-)

 

[Siliconwombat]

Well i feel a little stupid on the first one!
However on the second which was using the windows calculator I can't see any way of identifying the 12 as degrees? any hints?

Think I'll have to buy a proper calculator again!

You'll have to bear with me I'm coming back to physics after a long break to try and improve myself!

Thanks for your help :)

 

[ap123]

On my version of the Windows calculator, you can switch between "Standard" and "Scientific".
For the latter, there are radio buttons to choose from Degrees and Radians.

 

[Siliconwombat]

Actually scratch that, it seems to dislike my use of cos fullstop. Think Ill stick to google fr now ;)

 

[Siliconwombat]

Yeah I'm set on scientific and degrees but no matter which way I input the equation it only gives me 1150x12. It seems to ignore cos completely.

 

[Siliconwombat]

nvm its the opposite way round so input as 12 cos *1150.

Thanks for your help and please disregard my stupidity :)