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The ratio of gravitational force and ele...

The ratio of gravitational force and electrostatic repulsive force between two electrons is approximately (gravitational constant
`=6.7xx10^(-11)Nm^2//kg^2`, mass of an electron `=9.1xx10^(-31)kg`, charge on an electron `= 1.6 xx 10^(–19) C)`

A

`24 xx 10^(–24)`

B

`24xx10^(-36)`

C

`24xx10^(-44)`

D

`24xx10^(-54)`

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To find the ratio of the gravitational force to the electrostatic repulsive force between two electrons, we can follow these steps: ### Step 1: Write the formulas for gravitational and electrostatic forces. The gravitational force \( F_g \) between two masses \( m_1 \) and \( m_2 \) separated by a distance \( r \) is given by: \[ F_g = \frac{G m_1 m_2}{r^2} \] The electrostatic force \( F_e \) between two charges \( q_1 \) and \( q_2 \) separated by a distance \( r \) is given by: \[ F_e = \frac{1}{4 \pi \epsilon_0} \frac{q_1 q_2}{r^2} \] ### Step 2: Set up the ratio of gravitational force to electrostatic force. To find the ratio \( \frac{F_g}{F_e} \), we can divide the gravitational force by the electrostatic force: \[ \frac{F_g}{F_e} = \frac{\frac{G m_1 m_2}{r^2}}{\frac{1}{4 \pi \epsilon_0} \frac{q_1 q_2}{r^2}} \] ### Step 3: Simplify the expression. The \( r^2 \) terms cancel out: \[ \frac{F_g}{F_e} = \frac{G m_1 m_2}{\frac{1}{4 \pi \epsilon_0} q_1 q_2} \] This can be rewritten as: \[ \frac{F_g}{F_e} = \frac{G m_1 m_2 \cdot 4 \pi \epsilon_0}{q_1 q_2} \] ### Step 4: Substitute the values. Now, we substitute the known values: - Gravitational constant \( G = 6.7 \times 10^{-11} \, \text{Nm}^2/\text{kg}^2 \) - Mass of an electron \( m_1 = m_2 = 9.1 \times 10^{-31} \, \text{kg} \) - Charge of an electron \( q_1 = q_2 = 1.6 \times 10^{-19} \, \text{C} \) - The value of \( \epsilon_0 = 8.85 \times 10^{-12} \, \text{C}^2/\text{N m}^2 \) Substituting these values into the equation: \[ \frac{F_g}{F_e} = \frac{(6.7 \times 10^{-11}) (9.1 \times 10^{-31})^2 \cdot 4 \pi (8.85 \times 10^{-12})}{(1.6 \times 10^{-19})^2} \] ### Step 5: Calculate the values. Calculating the numerator: \[ G m_1 m_2 = 6.7 \times 10^{-11} \times (9.1 \times 10^{-31})^2 \approx 6.7 \times 10^{-11} \times 8.27 \times 10^{-61} \approx 5.55 \times 10^{-71} \] Now multiply by \( 4 \pi \epsilon_0 \): \[ 4 \pi \epsilon_0 \approx 4 \times 3.14 \times 8.85 \times 10^{-12} \approx 1.11 \times 10^{-10} \] So, the numerator becomes: \[ 5.55 \times 10^{-71} \times 1.11 \times 10^{-10} \approx 6.17 \times 10^{-81} \] Now, calculate the denominator: \[ (1.6 \times 10^{-19})^2 = 2.56 \times 10^{-38} \] ### Step 6: Final calculation of the ratio. Now, we can find the ratio: \[ \frac{F_g}{F_e} = \frac{6.17 \times 10^{-81}}{2.56 \times 10^{-38}} \approx 2.41 \times 10^{-43} \] ### Conclusion Thus, the ratio of the gravitational force to the electrostatic force between two electrons is approximately: \[ \frac{F_g}{F_e} \approx 2.41 \times 10^{-43} \]

To find the ratio of the gravitational force to the electrostatic repulsive force between two electrons, we can follow these steps: ### Step 1: Write the formulas for gravitational and electrostatic forces. The gravitational force \( F_g \) between two masses \( m_1 \) and \( m_2 \) separated by a distance \( r \) is given by: \[ F_g = \frac{G m_1 m_2}{r^2} ...
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The ratio of gravitational force and electrostatic repulsive force between two electrons is approximatly (gravitational constant =6.7 xx 10^(-11)Nm^(2)//Kg^(2) , mass of an electron =9.1 xx 10^(-31)kg , charge on an electron =1.6 xx 10^(-19)C )

If mass of an electron is 9.11xx10^(-31) kg, how many electrons will weight 2 kg?

Knowledge Check

  • If mass of an electron is 9.1xx10^(-31) kg, the number of electrons in 1 mg is

    A
    `1.09xx10^(27)`
    B
    `1.09xx10^(24)`
    C
    `9.1xx10^(28)`
    D
    `9.1xx10^(31)`
  • The rest mass of an electron is 9.11xx10^(-31) kg. Molar mass of the electron is

    A
    `1.5xx10^(-31) kg mol^(-1)`
    B
    `9.11xx10^(-31) kg mol^(-1)`
    C
    `5.5xx10^(-7) kg mol^(-1)`
    D
    `6.02xx10^(23) kg mol^(-1)`
  • The ratio of electrostatic and gravitational force acting between electron and proton separated by a distance 5 xx 10^(-11)m , will be (charge on electron = 1.6 xx 10^(-19)C , mass of electron = 9.1 xx 10^(-31) kg , mass of proton = 1.6 xx 10^(-27) kg, G = 6.7 xx 10^(-11) N - m^(2)//kg^(2) )

    A
    `2.36 xx 10^(39)`
    B
    `2.36 xx 10^(40)`
    C
    `2.34 xx 10^(41)`
    D
    `2.34 xx 10^(42)`
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