Linear Momentum
943 kg·m/s
p = m × v (Runner)
Kinetic Energy
4,302 J
E = 1/2 m v² at contact
Impulse Force (Peak)
6,240 N
Δp / Δt impact transfer
Exit Velocity / YAC
+14.2 yds
Yards After Contact
BIOMECHANICAL & MOMENTUM VERDICT
CLEAN TRUCK (DEFENDER FLATTENED)
RaKai's lower center of gravity (32° shoulder incline) combined with 20.4 mph downhill momentum completely overwhelmed the upright tackler's lever arm. The defender's chest absorbed 6,240 N over an 85 ms impulse window, generating an unrecoverable backward torque of 480 N·m.
Δp_carrier = -282 N·s
Δp_defender = +564 N·s
Leverage Ratio: 1.48 (Under Pads)
Tackle Break Prob: 94.6%
The Physics of the "Truck Stick"
When an elite ball-carrier like RaKai or Derrick Henry "trucks" a defender, the outcome is governed by conservation of momentum ($p = mv$) and rotational torque around the defender's center of mass.
- Pad Level & Shoulder Dip: The lower player wins the collision. Lowering the shoulder places the point of contact below the opponent's center of gravity, inducing a backward rotational moment that lifts the tackler off their cleats.
- Impulse Duration ($\Delta t$): High leg drive extends the contact window while continuously applying forward force, converting an elastic deflection into a bulldozer drive.
Why Tacklers Get Pancake Flattened
Defenders caught hesitating or coming in with high posture experience an instantaneous center-of-pressure shift. When normal force between cleats and turf drops to zero, friction drops immediately:
- Deceleration G-Forces: Peak contact forces often exceed 35–45 Gs over 40–90 milliseconds, producing helmet recoil and immediate turf displacement.
- Arm Tackles vs. Stiff Shoulder: An arm tackle delivers less than 1,200 N of stopping resistance against a 228-lb runner generating over 6,000 N of forward impulse.