## Resistors in parallel

If the resistors are connected as in the figure, the resistors are connected in parallel. The electric current (electric current = electric charge that flows during a time interval) that enters the junction point is the same as the...

## Source of electromotive force (emf), internal resistance, terminal voltage

Electric current flows in a closed circuit, from high potential to low potential. When an electric current moves through a component of electrical resistance, there is a reduction in electrical potential energy because electrical energy is used on this...

## EMFs in series and parallel

If there are two or more sources of electromotive (emf) connected as shown in the figure, the emf is arranged in series. The equivalent voltage source (ε) is: ε = ε1 + ε2 + εn The equivalent internal resistance...

## Kirchhoff’s first rule

Kirchhoff’s first rule also called the rule of junction point states that the electric current that enters a junction point is the same as the electric current exit from that junction point. The junction point in an electrical circuit...

## Kirchhoff’s second rule

Kirchhoff’s second rule states that the change in electric potential on the circumference of a closed circuit is zero. Kirchhoff’s second rule is based on the law of conservation of energy which states that energy is eternal. To better...

## Electric power

Definition of electric power The power learned in the work and Energy is defined as the work done during a certain time interval. Work is a process of energy change so that power can be understood as a change...

## Angular momentum

Objects which moving straight have momentum that can be calculated using the equation: p = m v p = momentum (kg m/s), m = mass (kg), v = speed (m/s) The quantity of the rotational motion, which is identical...

## Moment of inertia

1. Moment of inertia of the particle Review a rotating particle. The particle with mass m is given the force F so that the particle rotates about the axis O. The particle is r apart from the axis of...

## Electric current

Definition of Electric current In a conductor such as copper, there are electrons that move randomly at high speed freely but not escape from the metal. Electrons that can move freely are called free electrons. Although the electrons move...

## Parabolic motion, work and kinetic energy, linear momentum, linear and angular motion – problems and solutions

1. A ball is thrown from the top of a building with an initial speed of 8 m/s at an angle of 20o below the horizontal. The ball hits the ground 3 seconds later. a) How far from the...