Question

Can someone help pls!!

Answer 1

• Total resistance is 10Ω
• Current through the ammeter is of 0.9 A

Explaination :

As we know that, if n resistances R1 , R2 and R3 .... Rn are joined in parallel the equivalent resistance is given as :

`\boxed{ \sf{ (1)/(R_p) \: = \: (1)/(R_1)\: + \: (1)/(R_2) \: + \: (1)/(R_3) \: \: .... \: (1)/(R_n) }}`

R1 = 20Ω

R2 = 20Ω

Putting the values,

`: \longmapsto \: \sf{ (1)/(R_p) \: = \: (1)/(20Ω)\: + \: (1)/(20Ω)}`

`: \longmapsto \: \sf{ (1)/(R_p) \: = \: (1 * 1)/(20)\: + \: (1 * 1)/(20)}`

`: \longmapsto \: \sf{ (1)/(R_p) \: = \: \: (1 \: + \: 1)/(20)}`

`: \longmapsto \: \sf{ (1)/(R_p) \: = \: \: (2)/(20)}`

`: \longmapsto \: \sf{ (1)/(R_p) \: = \: \: \cancel(2)/(20)}`

`: \longmapsto \: \sf{ (1)/(R_p) \: = \: (1)/(10)}`

`: \longmapsto \: \pink{\bf{R_p\: = \: 10Ω }}`

Current through the ammete:-

As we know that,

• 
  `\boxed{ \sf{I \: = \: (V)/(R ) }}`

Here ,

• I is current
• V is Volts
• R is resistance

Putting the values,

`\longmapsto \: \sf{I \: = \: (9)/(10 ) }`

`\longmapsto \: \red{\bf{I \: = \: 0.9}}`

Answer 2

Rp = 10 Ohms; I = 0.9 Amps

Step-by-step explanation:

Since, there are two resistors each with 20Ω connected in parallel, the total resistance of the combination (Rp) of the circuit is as follows:

i.e 1/Rp = (1/R1 + 1/R2)

1/Rp = (1/20Ω + 1/20Ω)

1/Rp = (1 + 1)/20Ω

1/Rp = 2/20Ω

1/Rp = 1/10Ω

To get the value of Rp, cross multiply

Rp x 1 = 10Ω x 1

Rp = 10Ω

Apply the formula

Voltage V = Current I x Total resistance Rp

I = V/Rp

I = 9V/10Ω

I = 0.9 Amps

Thus, the total resistance is 10 Ohms, the current through the ammeter is 0.9 Amps