Q.1.If it takes 8 minutes to boil a quantity of water electrically, ho...
Boiling point of water is 100° centigrade so if it reaches its boiling , nothing can , however it may take 4 minutes
Q.1.If it takes 8 minutes to boil a quantity of water electrically, ho...
Answer:
Introduction:
When boiling water electrically, the time it takes depends on the power of the heating coil. In this case, we are given that it takes 8 minutes to boil a certain quantity of water using a specific heating coil. We are then asked to determine how long it will take to boil the same quantity of water using the same heating coil, but with the current doubled.
Given:
- Time taken to boil water electrically = 8 minutes
- Current is doubled
Calculating the effect of doubling the current:
To understand the effect of doubling the current, we need to consider the relationship between current, power, and time.
Power:
The power (P) of an electrical device can be calculated using the formula:
P = V * I
where P is power in watts, V is voltage in volts, and I is current in amperes.
Time:
The time (t) taken to perform a certain task can be calculated using the formula:
t = Q / P
where t is time in seconds, Q is the quantity of heat in joules, and P is power in watts.
Analysis:
In this case, the power of the heating coil remains the same, as the same heating coil is being used. However, the current is doubled. Let's assume the initial current is I, and the new current is 2I.
Calculating the initial time:
Using the given information, we can calculate the initial time taken to boil the water using the formula:
t_initial = Q / (V * I)
Calculating the new time:
Since the power remains the same and the current is doubled, the new time can be calculated using the formula:
t_new = Q / (V * 2I)
Substituting the initial time equation into the new time equation:
We can substitute the initial time equation into the new time equation to find the relationship between the initial and new times:
t_new = t_initial / 2
Conclusion:
From the above equation, it can be observed that when the current is doubled, the time taken to boil the same quantity of water using the same heating coil is halved. Therefore, if it initially took 8 minutes to boil the water, it will take 4 minutes when the current is doubled.
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