Thomson's and Millikan's contributions to atomic theory:
Thomson is the first person, who suggest that the theory of the atom contains positive and negative particles and demonstrated the latter which are called "electrons".
Millikan: Millikan discovered that the weight of an electron is 1840 times smaller than a hydrogen atom that is having atomic mass 1.
Answer:
The Moon does not have any light of its own and it shines because its surface reflects sunlight. During a total lunar eclipse, the Earth moves between the Sun and the Moon and cuts off the Moon's light supply. When this happens, the surface of the Moon takes on a reddish glow instead of going completely dark.
Explanation:
Metabolism is when you don’t gain weight after eating a lot.
Alpha (α), beta (β-) and gamma (γ) decay. When the nucleus of an atom possesses either too many or too few neutrons compared to the number of protons it becomes unstable. These are called radioactive isotopes. Unstable nuclei split up in a process called radioactive decay and emit radioactive radiation.
Q1. The answer is b) studying chemicals containing carbon.
Pure chemistry, as its name suggests, is the study of pure, basic theory of chemistry, and has no applied aspect. On the other hand, there is applied chemistry with research for some intended purpose and application. Now let's take a look at the choices: effects of drugs on human (purpose is understanding drug effects), a cure for osteoporosis (applied aspect), an antidote for a new strain of virus (applied aspect) are examples of applied chemistry because they have some purpose. On the other hand, studying chemicals containing carbon has no applied aspect, it is a study because of pure knowledge.
Q2. The answer is d) structure of a muscle cell.
Among choices, only the structure of a muscle cell is not visible to human eyes. Imagine foam insulation, X-ray of a knee joint, a shape of a plant - all of these are visible to human eyes. However, if you want to see a structure of a muscle cell, you will need a microscope. The microscopes are able to magnify specimens and are used to see structures that you cannot see with naked eye.
Q3. The answer is d) responding.
An independent (manipulated) variable is variable that is not affected during the experiment. It is what experimenter controls. A responding variable is also called a dependent variable. The dependent (responding) variable is called dependent because it depends (it responds) on the independent variables. It is what is affected and what is observed during the experiment.