The Book of Everything

                    Scientific Studies

Very Short Questions: 

1.   What is scientific study?

Ans: A scientific study is a systematic and organized inquiry into natural phenomenon to acquire knowledge through observation, experimentation and analysis.

2.   Why is scientific study important?

Ans: Scientific study is important because it allows us to understand the natural world, make informed decisions and advance knowledge, leading to technological and societal progress.

3.   What are the steps involved in the scientific study?

Ans: The steps in a scientific study include identification of problem, literature review, hypothesis, experimentation, data collection, data analysis, discussion and conclusion.

4.   Write any one principle of scientific study.

Ans: One principle is the principle of falsifiability, which states that a scientific hypothesis or theory must be formulated in a way that it can be tested and potentially proven false through experimentation and observation.

5.   How is the scientific study used in different fields? Write in one sentence.

Ans: Scientific study is used in various fields such as medicine, engineering, environmental science and social sciences to address specific questions, solve problems and advance knowledge.

6.   How is scientific study communicated to public?

Ans: Scientific study is communicated to the public through channels like scientific journals, media and educational outreach programs to share discoveries and increase public understanding.

7.   What is an independent variable?

Ans: An independent variable is a variable that can be manipulated or changed by the researcher in an experiment to observe its effect on the dependent variable.

8.   What is a dependent variable?

Ans: A dependent variable is a variable that is measured or observed in response to changes in the independent variable.

9.   Define controlled variables.

Ans: Controlled variables are factors in an experiment that kept constant to ensure that the impact of the independent variable on the dependent variable can be accurately assessed.

10.  What are the basic unit in the scientific measurement?

Ans: Basic units include meter (length), kilogram (mass). Second (time), kelvin (temperature), Ampere (electric current), Candela (luminous intensity) and mole (amount of substance).  

11.  What is a derived unit?

Ans: A derived unit us a unit that is formed by combining basic units; Such as the Newton (N) for force, which is derived from the basic units of mass, length and time. 

Short Questions:

1.   How do controlling variables in scientific research impact the validity of results?

Ans: Controlling variables in scientific research enhances the validity of results by isolating the effect of the independent variable, ensuring that any observed changes in the dependent variable are more likely due to the manipulated factor rather than other variables.

2.   How do extraneous variables affect the accuracy of scientific research findings?

Ans: Extraneous variable s, if not controlled, can introduce unwanted variability, reducing the accuracy of scientific research findings. They may confound the results by influencing the dependent variable independently of the manipulated independent variable.

3.   What are the fundamental units used in scientific measurement and how are they related to derived units?

Ans: Fundamental units, such as meter, kilogram, second, Kelvin and so on are the basic building blocks. Derived units, like Newton (N) for force, are combinations of fundamental units and express more complex measurements. 

4.   Give the examples of independent, dependent and controlled variables in a scientific experiment.

Ans: If the effect of amount of sunlight is to be studied on the growth of a plant, the variables involved in this experiment can be categorized as below.

Independent variable: Amount of sunlight given to the plant.

Dependent variable: Growth of the plant.

Controlled variable: Type of soil used for the plant, amount of water given, amount of fertilizers.

  

5.   What is the role of extraneous variables in scientific research and how can they be controlled?

Ans: Extraneous variables can introduce unwanted variability. They are controlled by maintaining consistent experimental conditions, using randomization, or statical techniques to account for their effects.

6.   Draw the flow chart showing the sequence of steps in a scientific study.

Ans: The flow chart showing the sequence of steps in a scientific study is presented below.

Figure: A flowchart involving different steps of scientific study

7.   The independent variable is manipulated in an experiment, why?

Ans: A researcher intentionally changes or manipulates the independent variable in an experiment in order to observe its impact on the dependent variable. This change enables the controlled study of possible cause-and-effect relationships between variables.

8.   Test the validity of the given equation by performing unit wise analysis.

a. v² = u + at                                    b. s = ut + 1/2 at²                            c. v² = u² + 2as

d. F = ma                                         e. p = mv²                                   f. P = F/A

Ans:

 

a. Given, v2 = u+ at Replacing both sides with their units, (m/s)2 = m/s + m/s2 × s m2 s–2 = m s–1 + m s–1 m2 s–2 ≠ 2m s–1 Discarding the numerical value, the left-hand side and right-hand side does not have the same unit. Therefore, this relation is not valid.	b. Given, s = ut + 1/2 at2 Replacing both sides with their units, m = (m/s) × s + 1/2(m/s2) × s2 m = m + 1/2 m  m = 3/2 m  Discarding the numerical value, the left-hand side and right-hand side have the same unit. Therefore, this relation is valid.
c. Given, v2 = u2 + 2as Replacing both sides with their units, (m/s)2 = (m/s)2 + 2 (m/s2) × m m2/s2 = m2/s2 + 2 m2/s2 m2/s2 = 3m2/s2 Discarding the numerical value, the left-hand side and right-hand side have the same unit. Therefore, this relation is valid.	d. Given, p = mv2 ½ mv2 = mv2 Replacing both sides with their units, kg m/s = kg (m/s)2 kg m/s ≠ kg m2 /s2 Discarding the numerical value, the left-hand side and right-hand side does not have the same unit. Therefore, this relation is not valid.

 

1.   Differentiate between dependent and independent variables.

Independent Variable	Dependent Variable
The variables that do not depend on other variables are known as independent variable.	The variables that depend on other variables are known as dependent variables.
They can be manipulated or changed by the researcher.	They are what the researchers measure or observe.
They are also called cause variables.	They are also called effect variables.

 

2.   Differentiate between fundamental units and derived units.

Fundamental Units	Derived Units
Fundamental units are independent and not defined by other units.	Derived units are dependent and derived from the combinations of fundamental units through mathematical operations.
It is measured directly without any need for further calculation.	It is measured indirectly, involving calculations using fundamental units.
E.g. meter (m), kilogram (kg), second (s) etc	E.g. meter/ second (m/s), Newton/ meter2 (N/m2) etc