Some Experiments with the help of Multimeter

LED when exposed to light,it generate DC voltage:-

Now switch multimeter to the lowest DC voltage range available, and touch the meter's test probes to the terminals (wire leads) of the light-emitting diode (LED). An LED is designed to produce light when powered by a small amount of electricity, but LEDs also happen to generate DC voltage when exposed to light, somewhat like a solar cell. Point the LED toward a bright source of light with your multimeter connected to it, and note the meter's indication.

Motor Acts As Generator:-

Another source of voltage through energy conversion a generator. The small electric motor specified in the "Parts and Materials" list functions as an electrical generator if its shaft is turned by a mechanical force. Connect voltmeter (multimeter, set to the "volt" function) to the motor's terminals just as connected it to the LED's terminals, and spin the shaft with fingers. The meter should indicate voltage by means of needle deflection (analog) or numerical readout (digital).

If it difficult to maintain both meter test probes in connection with the motor's terminals while simultaneously spinning the shaft with fingers, one may use alligator clip "jumper" wires.

Multimeter  fuse checking:-

One may test the condition of a multimeter's fuse by switching it to the resistance mode and measuring continuity through the test leads (and through the fuse). On a meter where the same test lead jacks are used for both resistance and current measurement, simply leave the test lead plugs where they are and touch the two probes together. On a meter where different jacks are used, this is how one insert the test lead plugs to check the fuse.

Bread board continuity:-

Although multimeter is capable of providing quantitative values of measured resistance, it is also useful for qualitative tests of continuity: whether or not there is a continuous electrical connection from one point to another. For instance, test the continuity of a piece of wire by connecting the meter probes to opposite ends of the wire and checking to see the the needle moves full-scale. What would we say about a piece of wire if the ohmmeter needle didn't move at all when the probes were connected to opposite ends?

Digital multimeters set to the "resistance" mode indicate non-continuity by displaying some non-numerical indication on the display. Some models say "OL" (Open-Loop), while others display dashed lines.

Use meter to determine continuity between the holes on a breadboard: a device used for temporary construction of circuits, where component terminals are inserted into holes on a plastic grid, metal spring clips underneath each hole connecting certain holes to others. Use small pieces of 22-gauge solid copper wire, inserted into the holes of the breadboard, to connect the meter to these spring clips so that one can test for continuity.