Answer:
L = 1.545 m
Explanation:
Let the total length of the rod is L
now the torque must applied on the other end of the rod so that it will balance the torque due to weight of rock on other side of fulcrum
so we will have

so we have

F = 663 N


Answer:
Heat
Explanation:
The thermal energy is usually defined as a heat energy that occurs due to the increase in temperature. Due to this increasing temperature, the atoms, as well as the molecules, start to migrate at a much faster rate and rapid collisions occur with one another.
This temperature change that is involved in this process can be measured.
Thus, in thermal energy, heat (heat energy) is transferred from one body to another at different distinct temperatures.
The SI unit of heat is Joule.
Electricity. Ruler. 69. N.
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