Tag: zimsec physics notes

So what is energy then? We just said we can’t do work if we don’t have energy. We have already defined it, in less scientific terms though. Energy is basically the capacity to do work. The SI unit of energy is the Joule (J) and it is a scalar quantity as no direction is involved in it.

Remember that a current-carrying conductor produces a magnetic field around it. If the current direction is reversed, the magnetic field direction will be reversed too.

Electromagnetic waves belong to the electromagnetic spectrum. Light is a part of this spectrum. And the only part of spectrum that we are able to see is light. The rest of it, like radio rays, are not visible to us.

When a magnet is moved into and out of the solenoid, magnetic flux is being cut by the coil. The cutting of magnetic flux by the wire coil induces an e.m.f in the wire. When the solenoid is connected to a closed circuit, the induced current will flow through the circuit.

We are going to study about D.C. Circuits, D.C. is the abbreviate for direct current. In this tutorial, we’ll study how the arrangement of an electric circuit will affect the electrical properties like charge, current, e.m.f., p.d. and resistance.

Electric current is produced when electrons flow. These electrons always flow from a negatively charged to a positively charged end. This is the electron flow.