# Calculating the maximum reach of a crane which has a variable counter weight position

1. Dec 4, 2012

### SherlockOhms

1. The problem statement, all variables and given/known data

A large tower crane is used to move heavy objects
in a construction site. The crane uses a counter
weight with a mass of mw = 1w.0 Mg (mega
grams), and the top beam of the crane also has a
mass of mc = 1x00.0 kg which is evenly distributed
along the beam. The length of the top beam of
the crane is L = 5y0.0 m. The counter weight can
position a maximum distance - c = 1z0.0 m from
the vertical support of the crane, and the load can
be positioned a maximum distance of (L-c) from the vertical support of the crane. w,x,y and z refer to various integers.

b) While at its maximum reach, if the crane was to lift a mass of 1,000 kg and needed to
lift this mass at an acceleration of 0.25g , where should the counter weight be
positioned during this acceleration (distance – b)?

2. Relevant equations

Your standard distance from the fulcrum multiplied by weight equations.

3. The attempt at a solution

I've spent about an two hours trying to figure this out. I'm pretty stumped though. Don't have any workings as I don't have a clue as to what the idea of this problem is. I don't need a fully worked solution, just a bump in the right direction. Thanks!

2. Dec 4, 2012

### haruspex

Re: Calculating the maximum reach of a crane which has a variable counter weight posi

Try rewriting the given values in a more conventional algebraic form, like mw = 1000+100w kg. That at least should allow you to write out some equations. But the variables w and x will appear in the answer. I don't see enough information here to eliminate those. Neither do I see any use for the value c. Maybe that's because this is only part of a longer question.

3. Dec 4, 2012

### SherlockOhms

Re: Calculating the maximum reach of a crane which has a variable counter weight posi

Ok, I'm sorry. I may have been a little vague. This is my first post on here like. The integers w,x,y and Z are GIVEN integers. In my case w = 6, x = 2, y = 3 and z = 6.

4. Dec 4, 2012

### haruspex

Re: Calculating the maximum reach of a crane which has a variable counter weight posi

OK, so post your attempt at writing and then using the equation. Keep everything as just unknown variables for now, not using any of the actual numbers given.