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McCormack-Simple M
McCormack - Simple Machines
Question | Answer |
---|---|
When is Work done on an object? | Work is done when the object moves in the same direction that the force is acting |
What is the formula for Work? | Work = Force x Distance |
How does a machine help to do Work? | Machines make work easier |
What is the formula for Power | Power = Force x Distance / Time |
Give three ways machines help to do Work? | They can change the Size, Distance, or Direction of the Effort Force. |
Input Force (Effort) | The force you exert on a machine |
Output Force (Load) | The force the machine exerts on an object |
Mechanical Advantage | Mech. Adv. = Output Force/Input Force |
What is the Mech. Adv. of a Pulley that takes 25 N of effort to move a 100 N load? | Mech. Adv. = 100 N / 25 N = 4 |
What is an Incline Plane? | A simple machine with a flat, sloped surface |
What is a Wedge? | A simple machine that is thick on one end and tapers to a thin end on the other. |
What is a Screw? | A simple machine that is an incline plane wrapped around a cylinder. |
What is a Lever? | A simple machine rigid bar that is free to pivot on a fixed point |
What is a Fulcrum? | The fixed point that a lever pivots around. |
What is a Class 1 Lever? | A Lever with the fulcrum in the middle. |
Give one example of a Class 1 Lever? | A crow bar, can opener, or scissors |
What is a Class 2 Lever? | A Lever with the fulcrum on one end, the load in the middle and the effort on the end |
Give one example of a Class 2 Lever? | A wheel borrow |
What is a Class 3 Lever? | A Lever with the fulcrum on one end, load on the other end, and the effort in the middle |
What is a Wheel & Axle? | A simple machine made of two circular objects fastened together that rotate about a common axis |
Give one example of a Wheel & Axle? | A screw driver, tire, wheel and hub |
What is a Pulley? | A simple machine made of a groved wheel with a rope wrapped around it. |
What is a Fixed Pulley? | A mounted pulley that changes the direction of the force |
What is a Movable Pulley? | A moving pulley that changes the amount of input force |
What is a Block & Tackle? | A pulley system made up of fixed and movable pulleys. |
What is a Compound Machine? | A machine that has two or more simple machines |
What is a Watt? | A small unit of Power1 horsepower = 746 watts |
Calculate the Work if you move 60N up a ladder that is 11 meters tall? | W = FxD, 60N x 11m = 660 J |
What is the Power if you lift 125 N of weight 2 meters high in 5 seconds? | W = FxD, 125 N x 2m= 250 J P = W/t , 250 J/ 5 s = 50 W |
A ramp is 10 meters long and 2 meters high, what is the Mech. Adv.? | MA = Ramp Length/ Ramp Height = 10 m/2 m = 5 |
An wheel has an outer radius of 35 cm and an axle of 5 cm, what is the Mech. Adv.? | MA = Outer radius / Inner radius = 35 cm / 5 cm = 7 |
A lever is 12 meters long from the Effort to the fulcrum and 3 meters from the fulcrum to the Load, what is the MA? | MA = Length Input/ Length Output = 12m / 3 m = 4 |
What is the trade off if a Block & Tackle has a MA of 4? Effort goes down by 4 X but the ____________________________________ | Distance increases by 4 X. |