Maharashtra State Board Class 6 Science Simple Machines Textbook Exercises and Extra Question and Answers.
Classify the following as a lever,a pulley and an inclined plane :
A wedge, a needle, a staircase, a slide,the wheel of a flagpole, nutcrackers,scissors, an opener, an axe, a crane,a knife.
A wedge – Wedge
A needle – Inclined Plane
A staircase – Inclined Plane
A slide – Inclined Plane
The wheel of a flagpole – Wheel and Axle
Nutcrackers – Lever
Scissors – Lever
An opener – Lever
An axe – Wedge
A crane – Complex Machine
A knife – Wedge
Fill in the blanks using the proper word and complete the statements.
(a) The fulcrum in the centre, the load on one side, and the effort on the other side make a lever of the first order.
(b) The fulcrum in the centre, the effort on one side, and the load on the other side make a lever of the second order.
(c) The effort in the centre, the fulcrum on one side, and the load on the other side make a lever of the third order.
Which machines will you use to do the following work? Write their types.
(a) To remove the lid of a tin: Lever
(b) To lift bricks to the top of a tall building: Crane
(c) To cut vegetables: Knife
(d) To draw water from a well: Bucket and pulley system
(e) To hold a papad for roasting it: Tongs
Write the answers to the following questions in your own words.
(a) What is meant by simple machines ?
A simple machine is a device that simplifies work by allowing it to be completed with less effort and time. A simple machine usually has two or three parts. Simple machines include levers, wedges, pulleys, and inclined planes.
(c) What is meant by complex machines ?
The term complex machine describes machines that are interconnected and often consist of several simple machines. A complex machine has different parts that work together to accomplish a specific, often more specialized, task. Automobiles, airplanes, and industrial manufacturing equipment are examples of complex machines.
Why is this so?
(a) Traveller’s bags have wheels.
(a) A travel bag with wheels is very convenient for carrying heavy items. Wheels reduce friction, so you can roll the bag rather than carry it.
(b) Machines have to be maintained.
(b) It is necessary to maintain machines because they wear and tear over time. Over time, friction can damage machines and reduce efficiency. Dust, dirt, and weather conditions can cause erosion and rust. Regular maintenance, such as cleaning, lubrication and protection from environmental factors, ensures that the machine works correctly and is safe.
(c) A bicyle is said to be a complex machine.
(c) Bicycles are considered complex machines because they are made up of many interconnected components and systems that work together to enable human-powered transportation. Bicycles are made up of wheels, pedals, gears, brakes, and chains. Each part is a simple machine on its own (wheels as wheels and axles, pedals as levers), but combined and interacted, they create a more sophisticated and versatile machine. Bicycles are complex machines. .
