Answer:
Explanation:
We are given the following formula:
(1)
Where:
is the amount of heat
is the mass of water
is the specific heat of water
is the variation in temperature, which in this case is
Rewriting equation (1) with the known values at the right side, we will prove the result is
:
(2)
This is the result
Reactivity is the ability of matter that allows it to easily chemically combine with other substances.
Entropy is randomness.
It mostly applies to gas particles because they move around randomly and freely
Answer:
The pitch that he hears after the truck passes and is moving away is 819.6 Hz.
Explanation:
The pitch that he hears after the truck passes and is moving away can be calculated using the following equation:

Where:
: is the perceived frequency
: is the emitted frequency
: is the speed of sound = 340 m/s
: is the speed of the observer = 0 (he is not moving)
: is the speed of the fire truck
First, we need to find the speed of the fire truck. When it approaches the observer we have:




Hence, the speed of the fire truck is 25.05 m/s.
Now, we can calculate the pitch that the observer hears after the truck passes:



Therefore, the pitch that he hears after the truck passes and is moving away is 819.6 Hz.
I hope it helps you!
Remember opposites attract and same charges repel each other.
Object A= negatively charged.
Object A and B attract so B must be positively charged.
Object B and C repel so because B is positively charged C must also be positively charged.
Object C and D attract and because C is positively charged, D must be negatively charged.