# Frictionless Inclined Plane, solve for acceleration

## Homework Statement

An object is on a frictionless inclined plane. The plane is at an angle of 30 degrees with the horizontal. What is the object's acceleration?

a) 0.50g b) 0.56g c)0.68g d)1.0g e)0.87g

## Homework Equations

F=ma a = g.sin(theta)

## The Attempt at a Solution

I set it up where a = mg.sin(theta) / m where I then get a = g.sin(theta)
where it's: 9.8 (sin(30)) and my acceleration would be 4.9 m/s^2. However, that is
not an answer choice with my options given, where I am now completely lost.
I sincerely would appreciate any help!

For the answers, they are a number multiplied by g.

For the answers, they are a number multiplied by g.

So when I set up the equation to find the acceleration which I thought was 4.9, was that the wrong thing to do? What am I missing because I know this is an easy problem, but I'm having trouble with this...

You've said that your answer isn't in the options given, you should take another look at the options and consider what I posted above.

You've said that your answer isn't in the options given, you should take another look at the options and consider what I posted above.
Ohhhhh..... Okay wow, then if that's the case I believe it is answer choice A. Because the sin of 30 is 1/2. And for my acceleration, it's gravity x sin(30). That's what you meant right? I did solve it correctly after all I suppose^^

That's exactly it. :) With answers like those it's a good idea to either convert the answers so that they're not in terms of g (So a is 0.5g = 0.5 * 9.8 = 4.9) or to get your answer in terms of g (sin(30)g = 0.5g).

That's exactly it. :) With answers like those it's a good idea to either convert the answers so that they're not in terms of g (So a is 0.5g = 0.5 * 9.8 = 4.9) or to get your answer in terms of g (sin(30)g = 0.5g).

Thank you so very, very much Mike! Have a Blessed one!