Mechanical Advantage PDF

Mechanical advantage Effort = My effort! Resistance = working against It is a relationship between effort and resistance. effort distance resistance force MA =​ ​ = or resistance distance effort forc...

Mechanical advantage Effort = My effort! Resistance = working against It is a relationship between effort and resistance. effort distance resistance force MA =​ ​ = or resistance distance effort force ​ What is working against you when you are trying to lift an object? ​ Using a ramp (inclined plane) increases the effort distance so that less force is exerted. ​ To calculate the mechanical advantage for an inclined plane, divide the length of the incline (effort distance – what you do) by the height of the incline (resistance distance – what you are working against). ​ MA = effort distance resistance distance ​ While helping your family move, you must get all of the items into the back of a truck, which is 2 meters off the ground. You use an 8 meter ramp to push heavy furniture into the truck. What is the mechanical advantage of the ramp? ​ Refer back to your formula. How do you decide which to use? ​ Are you given distance or force? ​Calculate the mechanical advantage of a road that winds up a 5,000 meter mountain at a gentle slope for 25,000 meters? ​ A single, fixed pulley helps you reverse the direction of your lifting force. ​ The rope is pulled down to lift the weight up. ​ If you want to lift something that weighs 100kg, you have to pull down with a force equivalent to 100kg, which is 1000N. ​ If you want to raise the weight 1m into the air, you have to pull the loose end of the rope a total distance of 1m at the other end ​ Calculating MA for pulleys can be as simple as counting! ​ Just count the rope segments, excluding the one you will be pulling. ​ Adding more pulleys can reduce the effort you need to lift the weight. ​ Two pulleys and a rope looped around them supports the same 100kg mass (1000 N) with two sections of the same rope ​ This means you can lift it by pulling with just half the force (500 N)  ​ 2 sections of rope (not counting the section you begin pulling) = a MA of 2. ​ MA = Resistance force/effort force ​ 1000 N/500 N = 2 ​ Adding more pulleys can reduce the effort you need to lift the weight. ​ Two pulleys and a rope looped around them supports the same 100kg mass (1000 N) with two sections of the same rope ​ This means you can lift it by pulling with just half the force (500 N) ​ 2 sections of rope (not counting the section you begin pulling) = a MA of 2. ​ MA = Resistance force/effort force ​ 1000 N/500 N = 2 ​ Adding more pulleys can reduce the effort you need to lift the weight. ​ Two pulleys and a rope looped around them supports the same 100kg mass (1000 N) with two sections of the same rope ​ This means you can lift it by pulling with just half the force (500 N) ​ 2 sections of rope (not counting the section you begin pulling) = a MA of 2. ​ MA = Resistance force/effort force ​ 1000 N/500 N = 2 ​ Where was it easiest to lift the water bottle? ​ Where was it hardest to lift the water bottle? ​ Increasing the distance of the effort arm, decreased the amount of __________ used. ​ What is this called? You apply a force of 18 N on to the end of a lever to open a paint can lid. The resistance of the lid is 9 N. Calculate the MA. ​ Are you given distance or force? ​ A worker uses a board that is 4 m long to pry up a boulder. A small rock is used for a fulcrum and is placed 0.5 m from the resistance end of the lever. Calculate the MA of the board. ​ Three of your friends are all sitting on one end of a seesaw. The combined weight is 275 N. The length from the fulcrum to your friends is 2.5 m. The rest of the seesaw (from the fulcrum to you) is 4.5 m. What is the MA?  ​What effort force is needed to lift your friends? ​To determine the mechanical advantage of a wheel and axle, divide the radius of the wheel (effort distance) by the radius of the axle (resistance distance). ​ If the radius of the screwdriver handle is 10 cm and the radius of the screwdriver tip is 2 cm, what is the mechanical advantage? ​ How can you increase the mechanical advantage of the screwdriver? ​ Increase the radius of the handle (the wheel). ​ When the effort force is applied to a wheel, like a door knob, the axle turns with even greater force. This allows you to turn the doorknob with relatively little effort, while the axle of the doorknob applies enough force to slide the bar into or out of the doorframe. ​ If you apply a force of 10 N to a door knob and it turns with a force of 30 N, what is the MA of the door knob? ​ A truck has a wheel that has a radius of 60 cm. The axle that powers the wheel has a radius of 10 cm. What is the mechanical advantage of the truck wheel? ​ You apply a force of 5 N on a pencil sharpener handle. The pencil sharpener has a mechanical advantage of 13. What is the machine’s output force?