Find the mass of this boat using torque

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    Boat Mass Torque
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The discussion centers on calculating the mass of a boat using torque principles. Initially, the trailer scale reads 48 kg, but after moving the boat's center of gravity 0.15 m back, the scale reads 37 kg. The difference of 11 kg is identified as the weight of the boat. Using torque equations, the initial and final torques are calculated, leading to the conclusion that the mass of the boat is 48 kg. The calculations involve setting up equations based on the distances from the pivot and the forces involved.
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A Trailer carrying a boat is supported by a scale which initially reads 48-kg. The boat (and therefore its centre of gravity) is moved 0.15-m further back on the trailer. The scale now reads 37-kg. Find the mass of the boat.

Kinda looks like this:

_______\___boat___/__
______|_______________O_______________
|------6.0-m-----|

Well, I've been tryin this question for 30 mins and i can't seem to get the right answer. I know F(d) = F(d) (where 'd' is the distance from the pivote)
but i don't know how to solve for the mass. If any of you can figure out my diagram and know wut to do...please help lol :smile:

Edit: k forget the diagram its just confusing lol. Just remeber that the boat is on a trailer with one point on the scale and then 6 meters away is the wheel. So there are 2 pivots.
 
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The answer is 11 kg.First, calculate the weight of the trailer and boat before the displacement: 48 kg. Then, calculate the weight of the trailer after the displacement: 37 kg. The difference between these two is 11 kg, which is the weight of the boat.
 


To find the mass of the boat using torque, we can use the equation: torque = force x distance. In this scenario, the force is the weight of the boat and the distance is the distance from the pivot (scale) to the center of gravity of the boat. We can set up two equations using this information:

Equation 1: initial torque = final torque
Initial torque = (48 kg)(6.0 m) = 288 kg*m
Final torque = (37 kg)(6.15 m) = 226.05 kg*m

Equation 2: torque = force x distance
(48 kg)(6.0 m) = force x (6.0 m - x)
Where x is the distance from the pivot to the center of gravity of the boat when it is moved 0.15 m back.

Solving for x, we get x = 5.85 m. This means that the center of gravity of the boat is 5.85 m away from the pivot (scale) when it is moved 0.15 m back.

Now, we can plug in this value for x into equation 2 to find the force (weight) of the boat:
(48 kg)(6.0 m) = force x (6.0 m - 5.85 m)
force = 48 kg

Therefore, the mass of the boat is 48 kg.
 
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