Why a bulb glow dimmer in beginning and then brighter

Click For Summary

Discussion Overview

The discussion revolves around the behavior of a light bulb connected to an inductor, specifically why the bulb glows dimmer initially and then becomes brighter. The scope includes theoretical explanations and mathematical reasoning related to inductance and current behavior in circuits.

Discussion Character

  • Exploratory, Technical explanation, Homework-related, Mathematical reasoning

Main Points Raised

  • Some participants propose that the inductor prevents the current from switching instantaneously, causing the current to rise slowly to its final value.
  • One participant suggests that the rate at which the inductor allows current to rise is proportional to the voltage across it, leading to a differential equation that can be solved to find the current as a function of time.
  • A later reply questions the maximum value of voltage or current in the circuit.
  • Another participant states that the maximum value, which is the final steady-state value, will be equivalent to what would be obtained if the inductor were removed and replaced with a wire.

Areas of Agreement / Disagreement

Participants express differing views on the specifics of the current and voltage behavior, and while some explanations are presented, no consensus is reached regarding the maximum values or the implications of the inductor's behavior.

Contextual Notes

Limitations include the dependence on assumptions regarding the circuit configuration and the mathematical treatment of the inductor's properties, which are not fully resolved in the discussion.

amaresh92
Messages
163
Reaction score
0

Homework Statement


greetings
why a bulb glow dimmer in beginning and then brighter when it is connected to a inductor?
 
Physics news on Phys.org


Because, inductor won't let current to switch instantaneously, i.e., it will make current rise slowly to its final value.
If you work out the math by assuming that the rate at which inductor let's current to rise is proportional to voltage across it, i.e. dI/dt = (1/L) V, then applying KVL, you will come to a differential equation.
Solving the differential equation, you will get expression for current, i.e. current as a function of time, I(t), which will give you all the information you need.
 


thecritic said:
Because, inductor won't let current to switch instantaneously, i.e., it will make current rise slowly to its final value.
If you work out the math by assuming that the rate at which inductor let's current to rise is proportional to voltage across it, i.e. dI/dt = (1/L) V, then applying KVL, you will come to a differential equation.
Solving the differential equation, you will get expression for current, i.e. current as a function of time, I(t), which will give you all the information you need.

what will be the maximum value of votage or current?
 


The maximum value which is the final steady state value will be equivalent to what will be obtained if you remove the inductor and join with wire.
 

Similar threads

Which bulb will glow brighter in a series and parallel circuit?
  • · Replies 5 ·
Replies
5
Views
2K
Determining the Change in Bulb Brightness by Changing Circuit
  • · Replies 6 ·
Replies
6
Views
2K
High School Which makes a bulb glows brighter?
  • · Replies 49 ·
2
Replies
49
Views
29K
Can RGB LED simulate incandescent bulb 'glow'?
  • · Replies 3 ·
Replies
3
Views
3K
12V DC Motor in Light Fixture with Dimmer & 12V DC to 110V AC Inverter
  • · Replies 21 ·
Replies
21
Views
3K
Lightbulbs in parallel & brightness > counterintuitive
  • · Replies 8 ·
Replies
8
Views
17K
Measuring Power Consumption of a Light Bulb with a Dimmer Switch
  • · Replies 12 ·
Replies
12
Views
5K
Could this bulb resistance problem be modified ?
  • · Replies 3 ·
Replies
3
Views
2K
Triac - Power dissipated in light bulb
  • · Replies 51 ·
2
Replies
51
Views
20K
Do light bulbs store energy?
  • · Replies 14 ·
Replies
14
Views
2K