Answer:
D) Roger is incorrect. Only a chemical change is taking place as evidenced by the light and heat of the burning candles.
Explanation:
- A physical change is a change in which there is no formation of new substances. Examples of physical changes are the melting or the evaporation of a substance (all phase transitions are examples of physical changes): in such cases, there is no formation of new substances.
- A chemical change is a change in which new substances form. Examples of chemical changes are the chemical reactions: for instance, when a candle burns, a reaction is taken place (oxygen is burnt, transforming into carbon dioxide + heat + light, so this is an example of chemical change).
Therefore, the correct answer is
D) Roger is incorrect. Only a chemical change is taking place as evidenced by the light and heat of the burning candles.
Answer:
The Correct Answer Is A
Explanation:
Primary Sources Has The Ideas, Work, And Opinions Written By The Person Themselves, Eliminating Work And Ideas Being Added On To It In Secondary Sources
What's your question? is it seprete questions
In series circuit, Req = R₁ + R₂ + R₃ + ···
In parallel circuit,
<h3>Q7.</h3>
total resistance in the upper branch = R₂ + R₃ = R₂ + 2
R₂ + 2 = 12
R₂ = 10Ω
<h3>Q8.</h3>
Req = 1.7Ω