Scientific Study, Class 10

Solution of Scientific Study

Differentiate between:

a. independent variables and dependent variables 

The differences between independent variables and dependent variables are:

Independent Variables	Dependent Variables
1. The variables that are independent in an experiment are called independent variables.	1. The variables that depend upon independent variables of an experiment are called dependent variables.
2. These are the causes.	2. These are the effects.
3. These variables are also called predictors or regressors.	3. These variables are also called predicted variables.
4. These variables do not need complex mathematical procedures and  observation.	4. These variables are obtained after solving complex mathematical equations.
5. These variables are written horizontally on the graph.	5. These variables are written vertically on the graph.
6. Any change in dependent variables does not affect independent variables.	6. Any change in independent variables affects these variables.

 b. fundamental unit and derived unit

The differences between fundamental unit and derived unit are: 

Fundamental Unit	Derived Unit
1. This is the unit of a fundamental quantity.	1. This is the unit of a derived quantity.
2.   This unit is  independent of other units.	2. This unit is obtained from fundamental units.
3. There are only seven fundamental units: meter, kilogram, second, Kelvin, ampere, candela, and mole.	3. Derived units are formed in many types using the seven fundamental units, such as Newton, Pascal, Joule, Watt, Hertz, Ohm, etc.

c. fundamental quantity and derived quantity

The differences between fundamental quantity and derived quantity are:

Fundamental Quantities	Derived Quantities
1. They are independent of each other.	1. They are derived from the fundamental quantities.
2. In SI system, there are seven fundamental quantities.	2. The number of derived quantities is not fixed.

3. Answer the following questions in short.

a. What is scientific learning?

Scientific learning is a problem-solving process of establishing facts through testing and experimentation independently.

 b. What are controlled variables?

Controlled variables are the variables that a researcher tries to hold constant throughout the experiment.

c. Define variable.

Any quantity that varies during the span of an experiment is known as variable.

e. What is unit?

The reference standard with which we carry out the measurement of any physical quantity of the same kind is called unit.

d. What are dependent and independent variables in research?

A dependent variable is the factor or condition that we measure or observe in an experiment. 

An independent variable is the factor or condition that we can change in an experiment.

f. Define fundamental and derived unit.

The unit which is independent of other units is called a fundamental unit.

The unit which depend on two or more fundamental units or power of a fundamental unit is called derived unit.

g. How many dependent variables do you want in an experiment? 

I want a single dependent variable in an experiment for clarity and ease of interpretation.

h. Define a unit. Write its types.

The reference standard with which we carry out the measurement of any physical quantity of the same kind is called unit.

Units are of two types. They are fundamental unit and derived unit.

i. Name the fundamental units used in physics.

The fundamental units used in physics are meter (m) for length, kilogram (kg) for mass, second (s) for time, ampere (A) for electric current, kelvin (K) for temperature, mole (mol) for amount of substance, and candela (cd) for luminous intensity.

4. Answer the following questions in detail.

a. What are variables in research? Explain with examples.

Variables are measuring quantities, factors, or conditions that can be controlled or changed during an experiment.

In the experiment, 'To investigate the effect of the number of pulleys used in a block and tackle system on the effort applied to lift a load,' the variables are load, effort distance, load distance, number of pulleys used, friction produced in the system, etc.

Similarly, in the experiment, 'To examine the impact of different fertilizer types on the growth rate of plants,' the variables are type of fertilizer, growth rate of plants, plant species, initial plant size, amount of fertilizer applied, watering schedule, sunlight exposure, temperature, soil type, and other environmental conditions.