{"id":1848,"date":"2022-11-18T15:00:42","date_gmt":"2022-11-18T09:30:42","guid":{"rendered":"https:\/\/www.aplustopper.com\/?p=1848"},"modified":"2022-11-19T15:27:16","modified_gmt":"2022-11-19T09:57:16","slug":"newtons-laws-motion","status":"publish","type":"post","link":"https:\/\/www.aplustopper.com\/newtons-laws-motion\/","title":{"rendered":"Newton’s Laws Of Motion"},"content":{"rendered":"
A body can not change its state of motion<\/a> by itself. If the object is at rest it will remain at rest and if it is in uniform motion, it continues to be in motion unless some external force<\/a> is applied on it.<\/p>\n Inertia:<\/strong> (a) Inertia of rest:\u00a0<\/strong>If the body is at rest, it will continue to be at rest unless some external force is applied on it. Examples are following. (b) Inertia of motion:\u00a0<\/strong>When a body is in uniform motion, it will continue to remain in its uniform motion, i.e. it resists any change in its state of motion due to inertia of motion. Situations involving inertia<\/strong> Relationship between Inertia and Mass:<\/strong> Inertia and Mass<\/strong><\/p>\n Effects of Inertia<\/strong><\/p>\n Aim:<\/strong> To investigate the relationship between inertia and mass. Results:<\/strong> Conclusion:<\/strong>\n
\nWhen F = 0 (No resultant force)
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\n<\/li>\n<\/ol>\n
\nThere is an inherent property of an object by virtue of which it cannot change its state of motion or rest by itself. This property is called ‘inertia’<\/strong>.
\nInertia is of two types\u2013 inertia of rest and inertia of motion.<\/p>\n
\nExamples:<\/strong>
\n1. When a train at rest starts moving suddenly, a passenger standing inside the compartment tends to fall backward.
\n2. When a carpet is beaten up with a stick, the dust particles are detached.
\n3.\u00a0<\/b>When a bullet is fired into a glass pane, it pierces a hole only at the pt where the bullet hits the glass without breaking the entire glass pane into pieces.<\/p>\n
\nExamples:<\/strong>
\n1. when a person jumps out of a moving bus, he should run in the direction in which bus is moving otherwise he will fall down.
\n2. A train moving with a uniform speed and if a ball is thrown upwards inside the train by a passenger, then the ball comes back to his hand.<\/p>\n
\nThe inertia of an object is the tendency of the object to remain at rest or, if moving, to continue its uniform motion in a straight line.<\/p>\n\n\n
\n <\/td>\n \u00a0The inertia of an object is the tendency of the object to remain at rest or, if moving, to continue its uniform motion in a straight line.
\nIn Figure (a), when the bus moves forward suddenly, the feet of the passenger are made to move forward. The inertia of his body tends to remain at rest. Hence, the passenger falls backward.
\nIn Figure (b), when the bus slows down suddenly, the feet of the passenger are brought to rest. The inertia of his body tends to continue moving forward. Hence, the passenger falls forward.<\/td>\n<\/tr>\n\n <\/td>\n \u00a0A 50 cent coin is placed on a cardboard covering the top of a glass. After the cardboard is pulled quickly, the 50 cent coin hovers over the top of the glass for an instant before dropping into the glass. The coin hovers for an instant because of its inertia.<\/td>\n<\/tr>\n \n <\/td>\n \u00a0When a book placed in the middle of a stack of books is pulled out horizontally with a quick jerk, the books above it tend to stay at rest due to inertia.<\/td>\n<\/tr>\n \n <\/td>\n \u00a0When very little tomato sauce is left in the bottle, the bottle is given a quick downward jerk to force the sauce out of the bottle. When the bottle moves, the sauce in it moves together. When the bottle is stopped suddenly, the inertia of the sauce keeps it moving downward and out of the bottle.<\/td>\n<\/tr>\n \n <\/td>\n \u00a0Figure shows a driver crashing his car without wearing a safety belt. Both the driver and the car were travelling at a very high speed. When the car was stopped suddenly, the inertia of the driver caused him to be thrown forward, thus injuring himself.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
\nLarger the mass of the body, larger is the inertia.
\nExample:<\/strong>\u00a0It is more difficult to stop a cricket ball than a tennis ball.<\/p>\n\n
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\nA stick is used to jerk the branch of a guava tree. At the end of the branch, there is a big guava. The guava tends to remain in its original state of rest due to its inertia. This will cause its stalk to snap and the guava will fall to the ground.<\/li>\n
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\nWhen a sheet of tissue paper is pulled quickly from a tissue box, the box will not move. The inertia of the box causes it to resist motion and remain at rest.<\/li>\n
\n \u00a0 \u00a0
\nThe blade of a hoe can be fitted tightly to its wooden handle by hitting the end of the handle against a hard surface as shown in the figure. The mass of the blade of the hoe is big and its inertia causes it to continue moving although the handle has been stopped, thus fitting it tighter to the handle. Likewise, the head of a hammer can be fitted into its handle this way too.<\/li>\n
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\nAfter an initial push, an ice skater glides almost effortlessly on an icy surface because of inertia.<\/li>\n
\n<\/p>\n\n
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\nDue to its very large mass, a ship has a very large inertia. It cannot be stopped guickly even during an emergency. A very strict navigation system is needed to guide a ship when reaching a port, sailing near rocks and icebergs as well as in busy sea routes like the Straits of Malacca to prevent accidents from happening.<\/li>\n
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\nWhen a rear-end collision occurs, the car and the body of the driver move forward suddenly. The headrest supports the head of the driver when it is thrown backward.<\/li>\n
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\nAn aeroplane has a large mass. It cannot be stopped easily when it lands at airports due to its large inertia. Therefore, a very long runway is required for the aeroplane to stop safely.<\/li>\n
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\nA steel structure is fitted in the space between the driver and the load of a timber lorry. This steel structure prevents any log from moving forward and knocking against the driver compartment when the lorry stops suddenly.<\/li>\n
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\nWhen a car stops suddenly during an accident, the driver continues to move forward because of inertia. The safety belt and airbag prevent the driver from crashing into the windscreen and injuring himself.<\/li>\n<\/ul>\nExperiment 1<\/strong><\/h3>\n
\nProblem:<\/strong> What is the relationship between inertia and mass?
\nHypothesis:<\/strong> The inertia of a body increases when its mass increases.
\nVariables:<\/strong>
\n(a) Manipulated variable: Mass
\n(b) Responding variable: Inertia
\n(c) Fixed variable: Type of hacksaw blade (The same blade is used throughout the experiment)
\nOperational Definition:<\/strong> Period of oscillation is an indicator for inertia, the responding variable. The bigger the period of oscillation, the bigger is the inertia.
\nMaterial:<\/strong> Plasticine
\nApparatus:<\/strong> Hacksaw blade, G-clamp, stopwatch
\nMethod:<\/strong><\/p>\n\n
\n<\/li>\n
\n1. Tabulation of results.
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\n2. Graph of period, T against mass m.
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\nDiscussion:<\/strong><\/p>\n\n
\nWhen the mass of a body increases, the body becomes more reluctant to change its state of rest or motion. This means that the inertia of a body increases when its mass increases.<\/p>\n (B) Newton’s Second Law of Motion<\/strong><\/h3>\n