Answer:
-10 m/s²
Explanation:
a = Δv / Δt
a = (20 m/s − 50 m/s) / 3 s
a = -10 m/s²
No scientific testing has been made to check for ion transfer, and the claims are purely empirical. Also, nine out of ten people is hardly a representative sample, and the people can claim whatever they want since "feeling" is subjective. This is most likely a pseudoscientific claim, made to sound legitimate to consumers. The best answer is choice D.
Answer:
The well is 7.1 meters deep.
Explanation:
The formula to use here is the distance in a uniformly accelerated motion:

where d stands for distance, t for time, a for acceleration, v0 and d0 for initial velocity and distance, respectively. Since the initial distance and velocity are both zero, we are left with the first term. The coin is in free fall and so it is accelerated by gravity:

The well is 7.1 meters deep.
3.6 kg.
<h3>Explanation</h3>
How much heat does the hot steel tool release?
This value is the same as the amount of heat that the 15 liters of water has absorbed.
Temperature change of water:
.
Volume of water:
.
Mass of water:
.
Amount of heat that the 15 L water absorbed:
.
What's the mass of the hot steel tool?
The specific heat of carbon steel is
.
The amount of heat that the tool has lost is the same as the amount of heat the 15 L of water absorbed. In other words,
.
.
.