Three resistors connected in series have potential differences across them labeled /\V1 , /\V2 , and /\V3. What expresses the potential difference taken over the three resistors together

Explanation:

We are given that three resistors R1, R2 and R3 are connected in series.

Let

Potential difference across

Potential difference across

Potential difference across

We know that in series  combination

Potential difference ,

Using the formula

Hence, this is required expression for potential difference.

freezing

deposition

condensation

explanation;

melting also called fusion is the process where solid becomes liquid, sublimation is the process where solid becomes gaseous without first changing to liquid, deposition involves change from gaseous to solid state, freezing involves change from liquid to solid, boiling or evaporation involves change of liquid to gaseous state, while condensation is the change from gaseous state to liquid state.

endothermic reactions involves absorption of heat from the surroundings or the environment while exothermic reactions involves loss of heat energy to the surroundings.

in this case, sublimation, evaporation and melting are endothermic reactions (gain energy from the environment) while, freezing, deposition and condensation are exothermic (loss of energy to the surroundings) reactions.