You place a mass of 250 grams on the measurement tray of a triple beam balance and then set the rider on the 500 gram beam to the 200 gram mark (the other riders are set to 0 grams). which of the following statements is true?

Explanation:

Althoug the list of statements is not provided, you can assure that the pointer will not be lined up with the zero mark, but above the zero mark.

A triple beam balance is very precise instrument, of common use in most labs, used to measure masses. It has three beams. Each beam works for different precisions and mass increments. One beam measures 1 g increments, other beam measures 10 g increments, and the other one 100 g increments.

If you place a mass of 250 grams on the measurement tray, then the weight will be balanced in the beams with 200 grams in the beam that reads increments of 100 g and 50 grams in the beam that reads increments of 10 g. When this is the situation, the weight is completely balanced, and the pointer will be lined up with the zero mark. But this is not the case.

When the rider on the 500 gram beam is set to the 200 gram mark, and the other riders are set to 0 grams, the weight of the mass (250 g) on the tray is greater than the force exerted by the rider on the beam (200 g) and so the tray will be below the level of balance, and the beam will be above the level of balance. The level of balance is indicated when the pointer is lined up with the zero mark.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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