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.
C, they are transverse and travel at the speed of light
If you neglect air resistance, then you can solve for the horizontal distance using the formula:
dx=vixt
Where:
dx = horizontal distance
vix = initial horizontal velocity
t = time in flight
Now you can see that you have all the given you need.
vix= 2km/h
t = 0.25 hours
We use hours because you need the units to be the same. So just plug that in your equation and you will have your answer:
dx = vixt
=(2km/h)(0.25h)
=0.5km
This means that the answer to your question is B.
As water vapour cools, it changes back into liquid form. drops come together to form 'clouds'? maybe