how to make a simple working model of 'electric bell? what are the things needed for this?
For a simple electric bell, you would need
A gong
A 9V battery
A switch
A DC motor with a circular pulley
A long bolt with two nuts and two small bolts
A connector
You can construct it on a base. First take a base. Then take the long bolt and place the gong in between the two nuts on an end of the bolt. Then stick the bolt vertically on the base in such a way that the gong comes on the upperside. Then take the pulley and stick the small bolts on it on the end in such way that the bolts are half outside the pulley then put the pulley onto the DC motor. Now take the connector, the switch and the DC motor and connect them all together. Now take the 9V battery and connect it with the connector. Now stick the battery on the base. And the simple electric bell is ready.
The working: When the switch will be pressed, the circuit will be complete and the current will make the motor to rotate. This will make the pulley to rotate and the two small bolts on the pulley will hit the gong simultaneously thus producing the sound.
A gong
A 9V battery
A switch
A DC motor with a circular pulley
A long bolt with two nuts and two small bolts
A connector
You can construct it on a base. First take a base. Then take the long bolt and place the gong in between the two nuts on an end of the bolt. Then stick the bolt vertically on the base in such a way that the gong comes on the upperside. Then take the pulley and stick the small bolts on it on the end in such way that the bolts are half outside the pulley then put the pulley onto the DC motor. Now take the connector, the switch and the DC motor and connect them all together. Now take the 9V battery and connect it with the connector. Now stick the battery on the base. And the simple electric bell is ready.
The working: When the switch will be pressed, the circuit will be complete and the current will make the motor to rotate. This will make the pulley to rotate and the two small bolts on the pulley will hit the gong simultaneously thus producing the sound.