Basic Physics

# Author: Alexsander San Lohat

I am from East Flores / Lembata. Physics teacher at SMAN 2 Nubatukan, Lewoleba, Lembata, East Nusa Tenggara, Indonesia

## Dielectric

A capacitor can function if both conductor plates do not touch each other so that the electric charge does not move from one conductor to another. Likewise, so that the electric charge does not move from the conductor to the air, the space between the two conductors must be a vacuum. In the topic about the parallel plate, the capacitor has been discussed the capacitance of parallel plate capacitors which are separated by a vacuum. The capacitance of the capacitor in a vacuum has limitations so that to enlarge the capacitance, placed dielectric between the two plates.

A dielectric is an insulator that separates the two plates or sheets of the conductor on the capacitor. Isolators are materials that cannot conduct the electric current, for example, plastic, glass, paper, or wood. The dielectric function is to increase the capacitance so that the capacitor can store more electric charge and the electric potential energy. Continue reading “Dielectric”

## Electrical energy stored in capacitor

The capacitor is composed of two-conductor plates and between the two conductors, there is a dielectric. At first, the two conductors are electrically neutral. In order for the capacitor to function, each plate or sheet of the conductor must be electrically charged, where the amount of the electric charge in each conductor is equal but different in type. Suppose that one of the charged conductors is Q = +10 Coulomb, the other conductor is Q = -10 Coulomb. The existence of the same large but opposite type of electric charge in both conductors generates an electric field between the two conductor plates, where the direction of the electric field is from the positive charge to the negative charge. In addition, there is also an electric potential difference between the two conductors, where positively charged conductors have a higher electric potential while negatively charged conductors have lower electric potential. Continue reading “Electrical energy stored in capacitor”

## Equation of capacitor circuit

A capacitor has a certain capacitance. If the required capacitance is not available, can be connected to two or more two capacitors to obtain the required capacitance. In order to properly connected the capacitor, it needs correct knowledge about the capacitor circuit 🙂

Before studying the capacitor circuit, first, understand the following symbols. Two vertical lines on the capacitor symbol represent two conductors on parallel plate capacitors. In the battery symbol, a longer vertical line represents a high potential (+) and a shorter vertical line represents a low potential (-). The horizontal line of both the capacitor symbol and the battery symbol represents the cable. Continue reading “Equation of capacitor circuit”

## Capacitance of capacitor

Definition of capacitance

A small glass can contain a little water, while a large glass can contain more water. The larger the volume of glass, the more water that can be contained. So each glass has the capacity or size of the ability to contain water. Like glass, capacitors also have the ability to store the electrical charges and the electrical potential energy. Capacitor capacity to store the electrical charge and the electric potential energy is called capacitance.

Factors affect capacitance

The size of the glass’s ability to contain water is determined by the volume of the glass. What about capacitors, what determines the size of the capacitor’s ability to store the electric charge? Continue reading “Capacitance of capacitor”

1. Quantities of vector and scalar

In addition to the fundamental and derived quantities, physical quantities can still be divided into two other types, namely scalar quantities and vector quantities. Quantities such as mass, distance, time and volume, are scalar quantities, quantities that only have magnitude but have no direction. Whereas magnitudes such as displacement, velocity, acceleration, and force are vector quantities, quantities that have magnitude and also have direction.

a. Difference between scalar and vector quantity

If you say the mass of a ball is 400 grams, this statement is enough for you to know the mass of the ball. You don’t need direction to find out the mass of the ball. Likewise with time, temperature, volume, density, etc. There are several physical quantities that cannot be expressed in magnitude only. If you say a child moves as far as 100 meters, then this statement is not enough. You might ask, where did he move? Is it north, south, east, or west? Likewise, if you say that you push the table with a force of 200 N. Continue reading “Addition of Vectors”

## Quantities of physics in the linear motion

1. Time interval

When an object moves from one place to another, the object needs a certain time interval. The time symbol is t (time). The international system unit of time is second (s).

2. Distance and displacement

Distance is the length of the path taken by an object. Distance is a scalar quantity, where the quantity does not depend on direction. The distance symbol is d and the international system unit is a meter (m). Continue reading “Quantities of physics in the linear motion”

## Uniform linear motion

Definition of uniform linear motion

An object experiences uniform linear motion if the velocity of the object is constant. Velocity includes the magnitude and direction of velocity. Direction of velocity = direction of displacement = direction of movement. The direction of the velocity of a constant object = the direction of motion of a constant object or the direction of motion of a fixed object = the object is moving straight. The magnitude of velocity or speed is constant = the speed is always the same all the time. Continue reading “Uniform linear motion”

## Nonuniform linear motion

Definition of nonuniform linear motion

Nonuniform linear motion is motion at constant acceleration. In other words, nonuniform linear motion = motion with the magnification of acceleration is constant and the direction of acceleration is constant. Direction of acceleration is constant = direction of velocity is constant = direction of displacement is constant = direction of motion is constant = the object moves in straight line. The magnitude of constant acceleration means that the magnitude of velocity or speed increases regularly. Continue reading “Nonuniform linear motion”

## Free fall motion

In everyday life, we often see objects that experience free-fall motion, for example, the motion of fruit falling from a tree, the motion of objects that fall or are dropped from a certain height. Why do objects experience free-fall motion? If observed at a glance, the object experiencing free fall as if it has a fixed speed, or in other words the object does not accelerate. The fact that happens, every object that falls freely experiences a constant acceleration. This reason causes free-fall motion including the example of nonuniform linear motion. How to prove that objects experiencing free-fall experience constant acceleration or its speed increase? Continue reading “Free fall motion”

## Uniform circular motion

In everyday life, we often encounter objects that move in a uniform circular motion. One example of an object that undergoes uniform circular motion is the second needle, the minute needle, and the clock needle on the analog clock. The second needle always rotates at an angle of 360o for 60 seconds (one minute) or rotates at a 6o angle for one second. The minute needle always rotates at a 360o angle for 60 minutes (one hour) or rotates at a 6o angle for one minute. Hour needle also always rotates 360o for 24 hours (one day). If an object moves in a regular circle such as a second needle, a minute needle, or a clock needle then the objects are said to be doing the circular motion. Can you think of examples of objects that move in a circular motion? Continue reading “Uniform circular motion”