Thermodynamics Question

[TomSawyer]

In a warehouse, a 200-kg container breaks loose from a forklift. The container slides along the floor at a velocity of 5 m/s. the force of friction between the block and the floor produces thermal energy at a rate of 10W. How far does the block travel before coming to rest?

I got the time it takes to come to rest by doing

KEi=1/2mv^2=1/2(200kg)(5m/s)^2=2500 J
KEf=0
2500J/10W= 250 s

but i can't figure out how to get the distance. could someone please help me?

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[thatscorrect7]

multiply by velocity

 

[TomSawyer]

omg..Lol...i'm so sorry. i was thinking way too hard and tried to use a variety of different equations. lol. thank you

 

[Charles_Carmichael]

Use kinematics. You know time (250s), initial velocity (5m/s), and final velocity (0m/s). You shouldn't just multiply the time by the initial velocity since the velocity changes.

Vfinal = Vinitial + at -------- use this to find acceleration

Then, use another kinematic equation (ie. timeless equation) to find distance.

 

[TomSawyer]

^^ thank you. i was wondering why my answer wasn't coming out correct even after multiplying by velocity.

Correct answer was 625 m btw.