Work question

[yellowcocopuffs]

TBR Physics (new book), ch2, prob 52
How much work is done by gravity on a 50kg box that is pushed up a 5m ramp to a new elevation 2m higher than its initial height?
>answer:-1000J.
What I don't understand is that I thought that negative work done on an object causes it to lose energy. Thus, if you increase an object's height, aren't you doing positive work on that object? Why is the answer to this problem negative?
Also, is there a tip/trick to solving work problems?

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[PiBond]

TBR Physics (new book), ch2, prob 52
How much work is done by gravity on a 50kg box that is pushed up a 5m ramp to a new elevation 2m higher than its initial height?
>answer:-1000J.
What I don't understand is that I thought that negative work done on an object causes it to lose energy. Thus, if you increase an object's height, aren't you doing positive work on that object? Why is the answer to this problem negative?
Also, is there a tip/trick to solving work problems?

The person pushing the block up the ramp is doing positive work, however gravity is doing negative work since the object is being displaced in the opposite direction than that of the force of gravity (pointing down the ramp).

Work = F d cos (theta)

cos (180) = -1

 

[GreenRabbit]

Scratch that.