Answer:
This question is incomplete as it lacks options, the options are:
Which change would be the most effective way to improve the validity of this experiment?
A) Increase the number of goldfish in each tank.
B) Increase the daily amount of food for each tank.
C) Create another group that is fed regular fish food.
D) Increase the number of tanks in each treatment group.
The answer is C
Explanation:
According to this question, an experiment is conducted by Trey to determine which fish food causes the most goldfish activity over a period of two weeks. In this experiment, the independent variable is the FISH FOOD which are; Swift Salmon food and Fast Flounder food. Other variables such as type of gold fish, amount of fish food, amount & type of water etc.
One of the ways to improve an experiment, which is lacking in this case is to have a CONTROL GROUP. Based on the fish foods used for each group, it is obvious that all groups in this experiment are experimental. Hence, creating another group that is fed regular fish food will serve as the CONTROL GROUP in order to compare with the experimental groups. This will improve the validity of the experiment.
Answer:
The change in entropy ΔS = 0.0011 kJ/(kg·K)
Explanation:
The given information are;
The mass of water at 20.0°C = 1.0 kg
The mass of water at 80.0°C = 2.0 kg
The heat content per kg of each of the mass of water is given as follows;
The heat content of the mass of water at 20.0°C = h₁ = 83.92 KJ/kg
The heat content of the mass of water at 80.0°C = h₂ = 334.949 KJ/kg
Therefore, the total heat of the the two bodies = 83.92 + 2*334.949 = 753.818 kJ/kg
The heat energy of the mixture =
1 × 4200 × (T - 20) = 2 × 4200 × (80 - T)
∴ T = 60°C
The heat content, of the water at 60° = 251.154 kJ/kg
Therefore, the heat content of water in the 3 kg of the mixture = 3 × 251.154 = 753.462
The change in entropy ΔS = ΔH/T = (753.818 - 753.462)/(60 + 273.15) = 0.0011 kJ/(kg·K).
50π m ≈ 157 m
Explanation:
100 rev/min (2π rad/rev) / (60 sec/min) = 3⅓π rad/s
d = ωrt = 3⅓π(0.50)(30) = 50π m ≈ 157 m
If the sentence is correct then write true. If not then write false and change the underlined word. For example #1, it says balanced forces DO NOT change the motion of an object. Is it true? If so write try on the line. If it’s not correct then write false on the line and change “do not” to “does”
You are in one place when you doze off, and in a different place when you awake.