why can you exert greater force on the pedals of a bicycle if you pull on the handlebars?

Answer 1

because the muscles in your arms pulling on the handle bars causes an equal and opposite reaction from the bars acting on your arms in a direction toward the bike. this force counteracts some of the upward force from the equal and opposite reaction from the pedals due to you pushing down with your feet. in other words, it allows you to counter some of the force by involving muscle from your arm in the force to hold you down to the bike.

Answer 2

You might find your answer in Newton's Third Law. For every action there is an equal and opposite reaction. So when you push down on the pedal, some of the down force is also redirected up causing you to lift slightly off the seat. That is why people on bicycles look like they are going slightly up and down as they pedal. If you firmly grip the handlebars, you will generally create a more solid form and less of the downforce will be lost.

Picture the difference as trying to stand from as sitting position. How would it differ if you stood on a movable surface like a trampoline than if you stood on a concrete slab? More of your downforce to the floor is applied in the opposite direction due to the static and solid nature of the concrete. The trampoline however eats much of the downforce and gives it back after you come to the end of your standing motion. So... does this help you out?

Answer 3

Because pulling on the handlebars adds more downward force to the pedals than your legs alone can produce. You're helping your legs out that way; think of pushing a door (that someone is blocking from the other side) with just your arms versus leaning and using your arms and legs.

Answer 4

Because you can use the additional force to exert more leverage on the pedals.

If you REALLY want to increase power, get some clipless pedals and compatible shoes. Your feet will be locked on the pedals (you can remove them quickly when you need to). Then, instead of pushing down on the pedals, just move your feet smoothly in a circle. Instantly you double the power output while lowering effort. It's amazing!

Answer 5

Yes, you can, if you stand on the pedals. Because if you sit, the extra downward force that you create goes to the seat, not the pedals. Your whole body needs to be involved in the process, without an additional support point. So it's unefficient, because you will use more energy just to get your body in the right position for the process. It helps for a short time, then it becomes too hard to maintain.

Answer 6

KINETIC ENERGY and MASS IN MOTION.

When you begin to from a stand still (sitting on your seat), your legs independantly exert a downward force on the peddles. This Kenetic Energy is transmitted to the back wheel and causes it to rotate and move you forward.

Then If you lift your butt up off the seat to go faster, now you are applying two diferent forces, both of which turn into Kenetic Energy. Force from your legs and you are using some Gravitational force from the weight of your body moving up and down. F1 + F2 = Ft (Total Force Applied) Your bodies mass in motion works for you with the assistance of gravity.

Thirdly, once you are going (peddling and standing up) using your ARMS as leverage and the handle bars to pull on you now employ a third force from your arms and leverage on the handle bars.
Simple equation would look like this

F1(legs) + F2(body weight) + F3(arm leverage)= Ft
Ft= Total Force Applied

More advanced equationing would take into consideration the co-efficients of Friction;
#1) The Friction of the bicycle design.
#2) The Friction of the ground to the rubber wheel
#3) The Friction force develoed by the AIR(At different sea levels too) Air Drag
These later co-efficients of friction while they are generally small amounts, they can be mesured and installed into a more advanced equation of Force Applied. Although of course these forces slow you down and are SUBTRACTED in the equation.

Take the equation above and Subtract
the following from it;

fe1(design friction) + fe2(wheel friction) + fe3(air drag) = Total positive energy resulting in SPEED and DISTANCE
I hope this helps you and doesn't confuss you!!!

By pulling on the handle bars you can force yourself down harder on the pedals.