Acceleration is change in velocity per unit of time mathematically expressed as dv/dt (in this case v being the magnitude, disregarding vector and direction)
Sparing the calculus, 60mph = 88 ft/sec
88ft/sec/3.3sec = 26.7ft/sec^2. Gravitational acceleration is 32.15 ft/sec^2
Or to put it another way 26.7/32.15 = 0.83 g forces. In other words, you weigh almost as much as your own body weight being sucked back into your seat.
Now we will get into vectors this time:
Now, if I may have fun and be a teen again for just a moment, let's imagine I have a cute, petite girl weighing 100 lbs in the seat. That means the 100 lbs is pulling downward, and the 83 pounds (0.83 x 100) back into her seat at right angles. The resultant force would be (using the Pythagorean theorem): Square root (100^2 + 83^2) = 130 lbs at about 40 degrees back from vertical toward her rear.
(angle = atan(83/100)
So I would say before accelerating to the nice, cute girl, "Hey babe. I can make you weight 30 pounds more for 3.3 seconds!" To which that will offend her (since girls always worry about their weight) and as soon as the car stops she will promptly get out and choose never to see me again! Hmmmm. That darned Sir Isaac Newton! He may be a hot sportsman, but man, he has trouble keeping the girls.
