This First assumption being made for this example is that the gloves have no weight. This is not a bad assumption because compitition gloves weigh only 8 ounces and don't provide much cushoning.

When a boxer throws a right hook, he twists his entire body along witht he punch, keeping his arm bet at a 90° angle. This loads the punch up with an execption amount of weight. For modeling porposes, we assume the boxer is capable of harnessing half his body weight. This would be 102.5 lbs or 46.5kgs.

A hook is one of the slowest punches because it requires the twisting of the torso as apposed to just arm movement.  The arm moves in a circular motion 180 degrees at a radius of 15inches (length from your shoulder to the elbow). This amounts to 4 feet in 1/2 second, 8ft/s or 2.4 m/s

Starting at rest and accelerating to 2.4m/s in 1/2 of a second means the arm has an acceleration if (2.3m/s - 0m/s)/.5s =  4.6m/s².

Next, if we assume that the opponents head is a stationary object absorbing all the force of the impact, The force on the opponents head can be modeled as:

    46.5kg * 4.6 m/s² = 214N

---