Carol, sorry to hear about your wreck, hope you recover smoothly.
"I did NOT KNOW that the front brake was stronger than the rear brake though, until I read the archived thread #73271 ("Is there a difference between front and rear discs/") yesterday. I was pretty much applying the same amount of pressure on each brake. Would that be enough (with the front brake being stronger) to instantaneously flip my bike like that though? Is it posssible that my front brake is Maladjusted and just locked up for some reason?"
How are the brakes now after the wreck? If the pads are still parallel to the rim and aren't ripped off, I think you can be assured the bike is OK. Stand next to the front wheel, lean down and apply the front brakes to see how they line up with the rim. Do the pads touch the rim evenly on the sides, that is, the pads are matching the sides of the rim? They're not too low and risk running off into the spokes?
Advances in technology have improved braking-performance tremendously. You can now apply the brakes with just 1 finger and lock up both tyres. This then requires some finesse in order to extract maximum deceleration rates safely. The exact physics behind braking is explained in this article:
Physics of Racing - Weight-transfer.
When you initially apply the brakes, your weight transfers from the seat to the handlebars (your arms feel more weight). This puts more weight over the front tyre (Lf in the article), and removes the exact same amount from the rear tyre (Lr). Tyre-traction is determined by vertical loading on the contact patch, so as your weight transfers to the front, the front-tyre has more traction than the rear. The amount that changes is based upon the braking-force (Bf). The faster you stop, the greater the weight-transfer.
The other reaction that occurs to the weight-transfer is the rotation of the bike verticaly around the front-tyre's contact patch. Depending upon how quickly you decelerate and the higher the COG (center-of-gravity) over the front contact-patch, the bike+rider system will tend to pivot forward. This lifts the rear and pushes down on the front. The front tyres gain grip and the rear loses grip. So you need to adjust the pressure you're squeezing on the levers and your body's position on the bike to account for this change in grip. We can separate the braking action into three distinct steps:
1. initial braking from steady-state speed is done by grabbing both of the brake-levers. Use only about 20-30% force on the levers and apply it gently. Do not just grab the leverls and pull, imagine you're squeezing a water-balloon between the lever and the handlebar and you want to do it gently so you don't pop the balloon.
2. increase braking-force by gently increasing the squeeze on the brake-levers to 50%. You'll feel the weight-transfer to the front as your weight is pushed forward from the deceleration (or you can imagine that the bike is pushing back). To counter thes weight-transfer, push back with your arms to shove your body to the back of the bike. It helps to straighten your arms and slightly lock your elbows.
3. maximum braking force is achieved by
increasing the front-brake lever squeeze even more AND at the same time,
decreasing the rear-brake lever force. You'll feel the rear tyres start to skid and slide as deceleration increases and transfering more and more weight to the front. So you lighten up the rear brakes to reduce its force on the rear tyre.
At the SAME time, you want to fully straighten your arm and push them foreward and push your body to the rear of the bike. You'll feel like you're sliding off the rear of the seat. This is fine because it actively puts more of the weight over the rear tyre that's getting light. In order to really extract FULL maximum braking force from the front-tyres, you squeeze the front-brakes even harder and you'll notice that the rear of teh bike comes off the ground. You want to scoot entire off the rear of the seat with your arms fully locked aiming forward to keep yoru body from flying over the handlebars. Since the rear is off the ground, the rear brakes do no good, so you lighten up on the rear brake lever. With your rear off the seat, you can lower your butt over the rear tyres and rest your belly on the seat. This lowers your COG and reduces the weight-transfer to the front wheel.
There's debate on which position the legs & feet should be in. Some people like to have one leg fully extended about 45-degree forward to push their body to the back of the bike. This places the pedal with the straight-leg lower than horizontal and the other one slightly above with a bent leg. Personally, I like to have both my legs slightly bent with the crankarms close to horizontal. This allows me to flex my knees and provide some suspension movement so absorb bumps under braking.
So in summary, braking is a dynamic event with the initial 50/50 split in weight-distribution moving shifting to the front tyre. This shift changes with time and braking-force, the faster you brake, the faster the weight shifts. There are modulations you have to do with the levers to account for this weight-shift and body-position adustments that needs to be done as well. So... I'd recommend practicing braking in an empty parking-lot or quiet street somewhere to get used to the feel. Start an easy pace, say 10-15mph and use the brakes just slightly. Then go do it again with slightly more pressure on the levers. Get used to that and repeat again. Get used to modulating the pressure on the levers as braking forces build (increase front, decrease rear). After a while, you won't have to think about this and it becomes natural.
I'll see if I can't find a picture somewhere of a biker under maximum-braking with his *ss hung out over the rear-tyre. I recall Alexi Greywall had an article in a mag. showing this sometime back in the '80s. Maybe I'll just go outside and make a video....