The weight of the meterstick is:

and this weight is applied at the center of mass of the meterstick, so at x=0.50 m, therefore at a distance

from the pivot.
The torque generated by the weight of the meterstick around the pivot is:

To keep the system in equilibrium, the mass of 0.50 kg must generate an equal torque with opposite direction of rotation, so it must be located at a distance d2 somewhere between x=0 and x=0.40 m. The magnitude of the torque should be the same, 0.20 Nm, and so we have:

from which we find the value of d2:

So, the mass should be put at x=-0.04 m from the pivot, therefore at the x=36 cm mark.
According to Newton's first law of motion, what happens to the ball is the ball rolls backward.
<h3>What is the first law?</h3>
This means that an object at rest or in motion will remain uniformly rectilinear and tend to be in that state if the net force on it is zero.
In this case, we have to think that the ball is at rest and the train is moving with a velocity that way, the reaction of the ball will be to go in the opposite direction to the motion.
See more about first law at brainly.com/question/3808473
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Answer:
The sun
Explanation:
In this system the energy of the sun heats the water in the pipe, producing a high pressured steam, which is used for moving a turbine and producing electricity, is a transformation of energy from solar to thermal, then to mechanical to electrical.