Question

electric kettle has three thermal coils A, B and C. To boil the same amount of water coil A, B and C take 2 min, 3 min and 6 min respectively when applied across same potential difference. If all three coils are operated together and same potential difference is applied across the combination, then to boil same amount of water

hor daso ji​

Answer 1

Answer:

In series combination, it will take 15 min

Explanation:

Answer 2

Given:

Time taken by coil A to boil the water= 2 mins

Time taken by coil B to boil the water= 3 mins

Time taken by coil C to boil the water= 6 mins

To Find:

Time taken to boil the water if all the coils are operated together

Solution:

Since the same potential difference is applied to the combination of coils,

⇒ The coils are connected in parallel combination

In parallel combination, if the time taken is tp then,

$\frac{1}{t_p} = \frac{1}{t_a} + \frac{1}{t_b} + \frac{1}{t_c}$

Here, ta , tb, and tc are the individual times taken by coil A, B, and C respectively.

Applying the formula,

$\frac{1}{t_p} = \frac{1}{2} + \frac{1}{3} + \frac{1}{6}$

Taking L.C.M as 6, we get:

= 3 + 2 + 1 / 6

= 6 / 6

= 1 minute⁻¹

So tp = 1 minute

Hence, it will take 1 minute to boil the same amount of water​ in combination with the coils.