Question

two coils require 20 minutes and 60 minutes respectively to produce same amount of heat energy when connected separately to the same source. if they are connected in parallel arrangement to the same source; the time required to produce same amount of heat by the combination of coils, will be min

Answer 1

When two coils are connected in parallel, the time required to produce the same amount of heat is the minimum of the individual times.

Step-by-step explanation:

When two coils are connected in parallel to the same source, the time required to produce the same amount of heat by the combination of coils will be the minimum of the individual times.

In this case, one coil requires 20 minutes and the other requires 60 minutes. Therefore, the time required when they are connected in parallel will be 20 minutes.

This is because when connected in parallel, the coils receive the same voltage but the total current is the sum of the currents flowing through each coil. So, the coil that requires less time to produce the same amount of heat will dominate the time taken by the combination.

Answer 2

To determine the time required for two heating coils connected in parallel to produce the same amount of heat as when connected separately, one can calculate the total resistance of the parallel combination and then use the power formula to find the total time.

Step-by-step explanation:

The student's question is related to the concept of heat energy production by coils when connected to a power source, which is a topic in physics. Two coils take 20 and 60 minutes respectively to produce the same amount of heat when connected separately to the same power source.

If these coils are connected in parallel, the total resistance of the system decreases, leading to an increased rate of heat production. To find the time required to produce the same amount of heat by the parallel combination of coils, we can use the formula for power (P=V^2/R) where V is the voltage and R is the resistance.

Considering the coils have resistances R1 and R2 that lead to the production of the same heat in different times t1 and t2, the resistances can be given by R1 = V^2*t1/H and R2 = V^2*t2/H, where H is the heat produced. Since they produce the same heat when connected for a specific time to the same source, H cancels out. When connected in parallel, the net resistance (Rnet) is given by 1/Rnet = 1/R1 + 1/R2, and the total time (T) required to produce the same amount of heat by the combination is T = V^2/Rnet*H.

Substituting and calculating using the provided times t1=20 minutes and t2=60 minutes, we can determine the total time T required for the parallel combination to produce the same amount of heat.