Farm Machinery

According to the universal tillage draft equation $D = A + B v + C v^2$, implement draft increases with forward speed $v$ primarily because:

Options:

• (A) Kinetic energy imparted to accelerate the soil slice increases with the square of speed ($C v^2$)
• (B) Friction between steel and soil drops to zero
• (C) Soil bulk density decreases
• (D) Soil moisture increases with speed