Machines are the devices which make our work easier and faster .
1) Machines help in gaining force. With the help of machines small force can be used to overcome a large force. e.g. screw jack can lift an object as heavy as car to change its tyres.
2) Machine can change the direction of the force so that force can be applied in a more convenient manner. e.g. rope passing over a wheel make easy to lift water from well.
3) Machines help in carrying out unsafe and dangerous tasks. e.g. pair of tongs can be used to lift a piece of burning coal from fire.
Learn about simple machines and their different types - lever, inclined plane, screw, wheel and axle, wedge, pulley, gears. Learn about terms that are used in simple machines
• Effort : An effort is the force applied to a machine to do mechanical work.
• Load : Load is the force that a machine exerts on a given body to be moved.
• Fulcrum : A fixed point about which the machine can turn.
Mechanical advantage of the lever = MA = effort arm/ load arm.
Velocity ratio- The ratio of the velocity of effort to the velocity of load is called the velocity ratio of machine: velocity of effort/ velocity of load.
Find out to which class of levers do the following objects belong- scissor, nut cracker, seesaw, wheel barrow, fishing rod. Learn how principle of inclined plane is used in screw and learn to make your own simple machines
Learnhive Lesson on Wheel and Axle
Learnhive Lesson on Screw
Learnhive Lesson on Wedge
Learnhive Lesson on Pulley
Learnhive Lesson on Technical Terms Related to a Machine