In daily life, everyone certainly cannot be separated from things related to numbers or calculations. To determine measurement results, quantities and measurement tools must be used. Quantities determined on the basis of fundamental quantities are called derived quantities.
Although it is a derivative, the existence of this quantity is no less important than the basic quantity. In fact, in everyday activities, humans often need derived quantities to determine the value of something. For example, finding the space or volume of the container to be used.
Apart from that, in schools, especially physics lessons, derived quantities are often discussed. Therefore, it is important to know and understand these quantities in order to facilitate the solution of various types of problems and other calculations that are often encountered.
Understanding derived quantities
The derived quantities are obtained after reducing the basic quantities. This quantity also contains international units and is a combination of several basic quantitative units. Therefore, it is very rare for the units of derived quantities to contain only one unit.
In this case, one fundamental quantity can produce many derivative quantities. For example, the basic measurements of length can be reduced to volume and area. In fact, examples of this quantity are often found in school, such as calculating speed, volume and area.
However, when compared to fundamental quantities, solving derived quantities is more complex. This is because there are many elements or parts that must be calculated using formulas. If you forget or don’t know, it means you have to reduce the original amount.
Types of derived quantities
The number of derived quantities is greater than the fundamental quantities. Therefore, the discussion is also extensive and the calculation method is very complex. To make it easier to identify the types of these quantities, pay attention to the following table.
1. Gaia
Force can be obtained by multiplying mass by acceleration, resulting in the formula F = m
a. The unit for this quantity in the International System of Units is kg m/s2 Or often expressed briefly using newton(n). In physics, a force is an interaction that can move objects.
An object can move if there is a force acting on it, either in the form of a push or a pull. This quantity also consists of different types, such as gravitational force, normal force, frictional force, magnetic force, machine force, spring force, muscular force, and many others.
2. Voltage
Work is defined as the amount of force needed to move or set an object in motion. Mathematically, this derived quantity can be obtained by multiplying the force (F) by the displacement (displacement). Effort is included in the category of scalar quantity or has no direction.
However, work has positive and negative poles. This quantity will have a positive value if it is in the direction of the body’s displacement, while it will have a negative value if it is in the opposite direction to the body’s displacement. The unit of work is kg m2 s-2 Or write it abbreviated using Joule (J).
3. Speed
To calculate how fast or slow an object is moving, you can use the velocity formula. This quantity divides the distance traveled (distance) by the travel time
Speed is directly proportional to distance, meaning that the faster an object moves, the further it can travel. However, speed is inversely proportional to time, meaning that the faster an object moves, the less time it takes.
4. Acceleration
Well, the acceleration will actually be obtained by dividing the object’s velocity (v) by the travel time
It should be noted that acceleration calculates both the change in speed and the change in time. Therefore, the final speed and time must be subtracted from the initial speed and time. Not only does it depend on the final value, you have to find the difference between the two.
5. Momentum
Aside from speed, moving objects also have momentum. This quantity will indicate the level of difficulty in stopping the speed or movement of the object. To stop this, an amount of work equal to mechanical energy is required.
The way to calculate momentum is to multiply mass (m) by velocity (v). In this case, momentum is directly proportional to velocity and mass. So, the greater the mass and speed of an object, the more difficult it is to stop its movement.
6. One
The amount of energy used at any given time is called power. In honor of the 18th century discoverer of steam, this quantity was given the unit of watts, taken from the name James Watt. Force has no direction, only a value, so it is a scalar quantity.
Power can be calculated by dividing the amount of work (W) by the time
7. Density
If mass is included in the fundamental quantity, then density is included in the derived quantity. Density is defined as the amount of mass of a substance per unit volume. Each object has a different character so it tends to have a different density.
The denser the arrangement of molecules in an object, the greater its density. On the other hand, if an object has a small density, the amount of matter per unit volume will be smaller. In general, solids have a high density.
8. Frequency
The discussion of frequency is closely related to sound. In physics, frequency is defined as the number of vibrations that can be produced each second. This quantity is denoted by the letter “f” and has units of hertz or usually abbreviated as Hz.
In general, sounds can be divided into 3 types based on their frequency. Ranging from ultrasonic (frequency less than 20 Hz), acoustic (frequency 20 Hz – 20,000 Hz), and ultrasound (frequency more than 20,000 Hz). Apart from that, this quantity can also be used to determine sound vibrations.
9. Electrical charging
Attractive or repulsive charges that can produce a force on other charges are called electric charges. The easiest way to tell whether an object has an electrical charge is to rub it.
When friction occurs, electrons in one object are transferred to another object. Well, objects that lose electrons will have a positive charge, while objects that gain electrons will have a negative charge.
10. Electrical voltage
Voltage is defined as the amount of electrical energy needed to transfer charge from both ends of a conductor. This arises because there is a source capable of transferring electrons from one pole to another, either directionally or back and forth.
To calculate the amount of voltage, you multiply the current (I) and the electrical resistance (R). The unit of this quantity is named after a physicist, Alessandro Volta (inventor of the battery). Therefore the unit of electric potential is expressed in volts.
11. Electrical resistance
Electrical resistance or resistance is the ratio between the amount of electrical potential in the body and the strength of the current. The size of this quantity can be affected by various factors, including temperature, conductor length, cross-sectional area, and type of material used.
The higher the temperature, cross-sectional area, and length of the conductor, the greater the resistance that develops in the circuit. Electrical resistance is divided into 3 types according to the arrangement of the circuit, which are series, parallel, and combined (parallel and series).
12. Spacious
Area quantities are found not only in physics lessons, but also in mathematics. In fact, subjects related to this number have been taught since elementary school, especially about flat shapes. Every object has a length and width that can certainly be calculated or its area known.
The commonly used formula for area is length times width. However, in reality this formula only applies to square areas. As for other flat areas, they also have their own area formulas, such as trapezoids, triangles, rectangles, parallelograms, etc.
13. Size
If area can be determined from a flat plane (two dimensions), then volume can be determined from a geometric plane (three dimensions). This means an object with known value for length, width and height. To calculate volume in general, you multiply these three elements.
As with flat shapes, the volume formula, pxlxt, cannot be applied to all spatial shapes. This formula is only suitable for calculating the volume of block-shaped objects, such as bricks, milk cartons, refrigerators, cabinets, lunch boxes, mattresses, etc.
Other shapes have their own volume formulas. For example, a cube has side(s) x side(s) x side(s), a cylinder has
com. xrxt2Balls with 4/3xxrxt3, a prism with base area (La) x height
14. Stress
The amount of force required to compress a surface area is called pressure. This quantity is calculated by dividing the number of acting forces (F) by the surface area of the plane (A). The greater the force acting on the body, the greater the pressure.
At the same time, the larger the surface area of the pressure zone, the smaller the pressure. In this case, attention must be paid to the shape of the pressure area before calculating it. Use the area formula according to the shape of the existing area.
After knowing the basic quantity, you can determine other quantities known as derived quantities. This quantity has more than one unit and can be calculated directly using measuring tools or indirectly using certain formulas.