Answer:
The best answer would be:
C. The scientific method was followed because the experiment tested the hypothesis and produced reliable results.
Explanation:
The purpose of an experiment is to test the hypothesis. It is true that having an experimental group and a control group was following the scientific method but the data gathering and documentation was also part of the scientific method. So the best answer would be C.
Writing the question is not necessary. It is merely part of forming a hypothesis. The scientific method does not require many scientists to perform the experiment, but it does require that the experiment be repeatable, so it can be tested again.
Answer:
C-Electrical energy changed into mechanical energy
Explanation:
Energy, according to the law of conservation of energy, is said to neither be created or lost but only interchangeable from one form to another. Energy exists in different forms. The process by which one form of energy changes to another is called TRANSFORMATION of energy.
However, certain household appliances or devices bring about this transformation of energy. For example, in a case where Tony turns a fan on when his room becomes uncomfortably hot. The fan uses an electric source to get powered on, which then facilitates the blades of the fan to move fast in order to bring about a cool atmosphere.
The fan converts ELECTRICAL energy (electric source) into MECHANICAL energy (moving energy).
Amount of Niobium-91 initially
= 300/91 =3.2967mol
2040 years = 3 ×680 = 3 half-lives
therefore, amount left = 0.4121mol
mass of Niobium-91 remaining = 0.4121 ×91 =37.5g
Use the ideal gas formula-----> PV= nRT
P= 2.50 atm
V= 250 mL= 0.250 L
n= 0.100 moles
R= 0.0821 atmxL/molesxK
T= ?
T= PV/nR
T= (2.50 atm x 0.250 L) / (0.100 moles x 0.0821)= 76.1 K