Question

Define atomic size. How does it vary.in a period & in a grou
Solve : An electrical iron uses a power of 1100 W when set
higher temperature. If set to lower temperature, it uses 330
power. Find out the electric current and the respective resist
of 220 V​

Answer 1

Answer:

Size of an atom is known as the atomis size

It increases down the group

And decreases from left to right

Answer 2

The resistance of the electric iron is 134.15 \Omega134.15Ω

Solution:

We know that P = VI

P = power; V = voltage and I = Current

Therefore, { I }=\frac { P }{ V }I=

V

P

Given at heating is maximum rateI=\frac { 840W }{ 220V }I=

220V

840W

Maximum current = 840W and minimum current = 220W

Then, I = 3.82A

The resistance of electric iron is { R }={ \frac { V }{ I } }=\frac { 220V }{ 3.82A } =57.59\OmegaR=

I

V

=

3.82A

220V

=57.59Ω

When heating is at minimum rate,{ I }=\frac { 360W }{ 220{ V } } =1.64{ A }{ R }=\frac { 220V }{ 1.64A } =134.15\OmegaI=

220V

360W

=1.64AR=

1.64A

220V

=134.15Ω "