physics help ! KE rolling without slipping?

Two uniform solid balls are rolling without slipping at a constant speed. Ball 1 has twice the diameter, half the mass, and one-third the speed of ball 2. The kinetic energy of ball 2 is 37.0 J. 

What is the kinetic energy of ball 1?

2 Answers

Relevance
  • 1 month ago
    Favorite Answer

    KE = linear KE + rotational KE = ½mV² + ½Iω²

    for a solid sphere total KE = ½mV² + (1/5)mV² = (7/10)mV²

    KE₂ = (7/10)m₂V₂² = 37

    KE₁ = (7/10)m₁V₁²KE₁ = (7/10)(m₂/2)(V₂/3)²KE₁ = (7/10)(m₂/2)(V₂²/9)KE₁ = (7/10)(m₂)(V₂²) (1/2)(1/9)KE₁ = (KE₂) (1/2)(1/9)KE₁ = (37) (1/2)(1/9) = 37/18 J

    • Login to reply the answers
  • Anonymous
    1 month ago

    E2 ≡ m2*r2^2*V2^2/r2^2 ≡ m2*V2^2

    E1 ≡ 0.5m2*r1^2*(V2^2/(9*r1^2) = m2*V2^2/18 = 37/18 joule

    • Login to reply the answers
Still have questions? Get your answers by asking now.