Physics Current Electricity

$l=\frac{V_{0}B\mathcal{l}}{R}=\frac{V_0*5*20*10^{-2}}{4+1}$         

  $2*10^{-3}=V_0*20*10^{-2}$

$V_0=\frac{2*10^{-3}}{20*10^{-2}}=\frac{2}{2}*10^{-2}=1*10^{-2}m/s$

V₀ = 1 cm/s

Suppose acceleration of wedge is a and acceleration of block w. r.t. wedge is a₁ then N cos60° = Ma = 16 a -> N = 32 a

For block w.r.t. wedge

N + 8a sin 30° = 8g cos 30°

N = 8g cos 30° - 8a sin 30°

->32a = 8g cos 30° - 8a sin 30°

->a = $\frac{\sqrt[]{3}}{9}g$  

Now for 8 kg,

$8gsin30°+8acos30°=m{a}_1$  

$a_1=g*\frac{1}{2}+\frac{\sqrt[]{3}}{9}g*\frac{\sqrt[]{3}}{2}$  

$=\frac{2}{3}g$  

In first condition R₁ = 36 $\Omega$  

In second condition R₂ = 18  $\Omega$

$P_1=\frac{V^2}{R_1}=\frac{{\left(240\right)}^2}{36}$               

$P_2=\frac{V^2}{R_2}+\frac{V^2}{R_2}=\frac{{\left(240\right)}^2}{18}+\frac{{\left(240\right)}^2}{18}$               

$P_2=\frac{{\left(240\right)}^2}{9}$               

So   $\frac{P_1}{P_2}=\frac{{\left(240\right)}^2/36}{{\left(240\right)}^2/9}=\frac{1}{4}$

x = 4

$\frac{1}{R_{eq}}=\frac{1}{R_1}+\frac{1}{R_2}=\frac{1}{4}+\frac{1}{4}$  

 R_eq = 2

$\frac{\Delta R_{eq}}{R_{eq}^2}=\frac{\Delta R_1}{R_1^2}+\frac{\Delta R_2}{R_2^2}$

$\begin{array}{l}\frac{\Delta R_{eq}}{4}=\frac{0.8}{16}+\frac{0.4}{16}+\frac{1.2}{16}\\ R_{eq}=0.3\end{array}$                

In given circuit inductor behave as a simple wire so resultant circuit will be

R_ef = 2 + 1 = 3 $\Omega$  

V = IR

$l=\frac{30}{3}=10A$  

Using Heat equation : H = i²Rt

=>192 = (4)² R (1)

H = (8)² R (5)

=>H = 3840 J

Energy required to melt

Q = $MS\Delta T+ML$  

$\Rightarrow 10^{-1}*2*10^3*10+10^{-1}*3.33*10^5$      

->3.53 * 10⁴ J

Heat produce in wire

H = l²RT

  $Q=3.53*10^4={\left(\frac{1}{2}\right)}^2*\left(4*10^3\right)*t$

$t=\frac{3.53*10^4*4}{4*10^3}=35.3sec$             

Since $5\Omega$ is connected across conductor so we can remove it.

$R_{eq}=1\Omega$

The basic unit of energy is a Joule (J), which is equal to one watt of power expended for one second. In the day-to-day scenarios such as household electricity consumption, joule is too small a unit to be convenient. For billing and metering purpose, it is measured in kilowatt-hours (kWh). Electrical energy is measured in kilowatt-hours (kWh) as the commercial unit. 1kWh = 1000 W * 3600 s 

For calculating the units consumed, we will be using the following formula 

Units = [Power (W) x Time (h)]/1000