Gravitational Force Calculations

Gravitational Force

Gravitational Force Between Two Objects

  • The problem aims to find the gravitational force (fgf_g) between two masses.
  • Given:
    • Mass 1 (m1m_1) = 70 kg
    • Mass 2 (m2m_2) = 52 kg
    • Distance (r) = 1.5 meters
    • Gravitational constant (GG) = 6.67x10116.67 \, x \, 10^{-11}
  • Formula:
    • F<em>g=Gm</em>1m2r2F<em>g = G \frac{m</em>1 m_2}{r^2}
  • Substituting values:
    • Fg=6.67×1011×70×521.52F_g = 6.67 \times 10^{-11} \times \frac{70 \times 52}{1.5^2}
  • Calculation:
    • Numerator: 6.67×1011×70×52=2.42788×1076.67 \times 10^{-11} \times 70 \times 52 = 2.42788 \times 10^{-7} (or 2.43×1072.43 \times 10^{-7} with rounding)
    • Denominator: 1.52=2.251.5^2 = 2.25
    • Fg=2.42788×1072.25=1.079057778×1071.08×107 NewtonsF_g = \frac{2.42788 \times 10^{-7}}{2.25} = 1.079057778 \times 10^{-7} \approx 1.08 \times 10^{-7} \text{ Newtons}

Calculator Usage

  • Entering scientific notation:
    • Using the "EE" function (or similar) on the calculator.
    • Example: 6.67×10116.67 \times 10^{-11} is entered as 6.67 EE -11.
  • Order of operations:
    • Calculate the numerator first, then the denominator.
    • Divide the numerator by the denominator.
  • Storing values:
    • Using the store (STO) button to save intermediate results for later use.

Common Mistakes

  • Incorrectly entering scientific notation into the calculator.
  • Forgetting to square the distance (r).
  • Not dividing the numerator by the denominator.

Gravitational Force Between Earth and Moon

  • Objective: To calculate the gravitational force between the Earth and the Moon.
  • Given:
    • Moon's mass (m1m_1) = 7.34×10227.34 \times 10^{22} kg
    • Earth's mass (m2m_2) = 6×10246 \times 10^{24} kg
    • Distance between centers (r) = 3.88×1083.88 \times 10^8 meters
    • Gravitational constant (GG) = 6.67×10116.67 \times 10^{-11}
  • Formula:
    • F<em>g=Gm</em>1m2r2F<em>g = G \frac{m</em>1 m_2}{r^2}
  • Substituting values:
    • Fg=6.67×1011×7.34×1022×6×1024(3.88×108)2F_g = 6.67 \times 10^{-11} \times \frac{7.34 \times 10^{22} \times 6 \times 10^{24}}{(3.88 \times 10^8)^2}