physics investigatory project- LDR. IATION ‘N LDR CONCLUSION Based on the obsewation above, it eam be cometuded that the LDR based. INTRODUCTION • A light dependant resistor(LDR) or a photoresistor or photocell . Physics Investigatory Project on LDR as Variable Resistor. Project Report Submitted On Light Dependence Resistance Â Submitted By: A. Varun Class â XII Kendriya Vidyalaya no. 2 Pondicherry.
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In the society, some times street lights glow in day time due to any reason.
Physics Investigatory Project On LDR | Richard Parker –
In mines area people face many difficulties due to absence of light in the nights. In frontier and hilly areas, people face many problems due to damaged street lights. For solve above these problems, we create a device in which the lights glow in night and in day time, they off automatically and don’t glow.
Due to use of it, we can solve above problems and can also save electricity and men’s power. Light Dependent Resistance [LDR] is a resistance, in which invesrigatory power of current depends on pproject presence of quantity of light present, i.
Accuracy of this circuit is more than accuracy of other circuits. By using laser, it can be used for security purposes.
It can be used to stop the wastage of electricity. The cost of circuit is low. This circuit saves the men’s power.
Light dependent resistor(LDR) – physics investigatory project
It consists of emitter, base, and collector. It conducts when forward biased investigatoory does not conduct when reverse biased. In the project, INdiode is used. In the project, we use relay of 6 ohms.
In project, we use carbon resistance of kilo-ohms, 1. We use a transformer of V for the circuit.
In the circuit, we use the capacitor of mfd and mfd. DC is flowed in the circuit. At this time, it becomes earth, so that no voltage flows through the base of transistor T 1.
Due to absence of positive voltage at base, emitter hasn’t negative voltage in the comparison of its base, so that transistor T 1 don’t conduct and no current flows through it.
But resistance of 1.
For conduction, investigztory has some negative voltage in the comparison of its base. But at this time, 4V DC investigatroy at base of transistor T 2so that emitter has highly negative voltage in comparison of its base, so that transistor T 2 inveetigatory conducts.
The collector of transistor T 2 is connected with relay coil, so that magnetic induction around relay coil will disconnect with rest point and connect with active point. So, According to the circuit, the bulb will glow. Now LDR has not zero resistance due to darkness, so that 6V DC line and kilo-ohms resistance, some positive voltage reach at the base of transistor T 1. The collector of transistor T 1 has positive voltage because 6V DC pass through 1. In this way transistor T 1 conduct and current start to flow in transistor T 1.
Transistor T 1 and resistance of 1.
Now, the above terminal of 1. From 3V approximate 1. DC reaches at base of transistor T 2. The collector of transistor T 2 has positive voltage by relay coil. But at this time, emitter has some negative voltage in the comparison of its base. So that the quantity of current which flows through transistor T 2 and relay coil will very low. Due to this, magnetic induction around relay coil will not more effective and pole point will disconnect with active point and connect with rest point.
According to the circuit, the bulb will glow. USES It can be used in street lights. It can be used in mines areas. It can be used in hilly areas.