{"id":36001,"date":"2022-11-25T16:57:18","date_gmt":"2022-11-25T11:27:18","guid":{"rendered":"https:\/\/tsboardsolutions.com\/?p=36001"},"modified":"2022-11-25T16:57:18","modified_gmt":"2022-11-25T11:27:18","slug":"ts-inter-1st-year-physics-notes-chapter-9","status":"publish","type":"post","link":"https:\/\/tsboardsolutions.com\/ts-inter-1st-year-physics-notes-chapter-9\/","title":{"rendered":"TS Inter 1st Year Physics Notes Chapter 9 Gravitation"},"content":{"rendered":"

Here students can locate TS Inter 1st Year Physics Notes<\/a> 9th Lesson Gravitation to prepare for their exam.<\/p>\n

TS Inter 1st Year Physics Notes 9th Lesson Gravitation<\/h2>\n

\u2192 Kepler’s Laws :
\nLaw of orbits (1st law) ‘.All planets move in an elliptical orbit with the sun is at one of its foci.<\/p>\n

\u2192 Law of areas (2nd law) : The line joining the planet to the sun sweeps equal areas in equal intervals of time, i.e., \\(\\) = constant.
\ni. e., planets will appear to move slowly when they are away from sun, and they will move fast when they are nearer to the sun.<\/p>\n

\u2192 Law of periods (3rd law) : The square of time period of revolution of a planet is proportional to the cube of the semi major axis of the ellipse traced out by the planet.
\ni.e., T2<\/sup> \u221d R3<\/sup> \u21d2 \\(\\frac{\\mathrm{T}^2}{\\mathrm{R}^3}\\) = constant<\/p>\n

\u2192 Newton’s law of gravitation (OR) Universal law of gravitation: Every body in universe attracts other body with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.
\nF \u221d m1<\/sup>m2<\/sup>, F \u221d \\(\\frac{1}{\\mathrm{r}^2}\\) \u21d2 F = G\\(\\frac{\\mathrm{m}_1 \\mathrm{~m}_2}{\\mathrm{r}^2}\\)<\/p>\n

\"TS<\/p>\n

\u2192 Central force : A central force is that force which acts along the line joining the sun and the planet or along the line joining the two mass particles.<\/p>\n

\u2192 Conservative force : For a conservative force work done is independent of the path. Work done depends only on initial and final positions only.<\/p>\n

\u2192 Gravitational potential energy : Potential energy arising out of gravitational force is called gravitational potential energy.
\nSince gravitational force is a conservative force gravitational potential depends on position of object.
\nV = \\(-\\frac{\\mathrm{Gm}_1 \\mathrm{~m}_2}{\\mathrm{r}}\\)<\/p>\n

\u2192 Gravitational potential : Gravitational potential due to gravitational force of earth is defined as the “potential energy of a particle of unit mass at that point”.
\nGravitational potential V = \\(\\frac{G M}{r}\\)
\n(r = distance from centre of earth)<\/p>\n

\u2192 Acceleration due to gravity (g) :
\nAcceleration due to gravity ‘g’ = \\(\\)<\/p>\n

\u2192 Acceleration due to gravity below and above surface of earth :
\n1) For points above earth total mass of earth seems to be concentrated at centre of earth.
\nFor a height ‘h’ above earth
\ng(h) = \\(\\frac{\\mathrm{GM}_{\\mathrm{E}}}{\\left(\\mathrm{R}_{\\mathrm{E}}+\\mathrm{h}\\right)^2}\\)
\nwhere h << RE
\ng(h) = g\\(\\left(1+\\frac{h}{R_E}\\right)^{-2}\\) = g\\(\\left(1-\\frac{2 \\mathrm{~h}}{\\mathrm{R}_{\\mathrm{E}}}\\right)\\)<\/p>\n

2) For a point inside earth at a depth’d’ below the ground mass of earth (Ms<\/sub>) with radius (RE <\/sub>– d) is considered. That mass seems to be at centre of earth.
\ng’ = g\\(\\left(1-\\frac{d}{R}\\right)\\)<\/p>\n

\u2192 Escape speed (v1<\/sub>)min<\/sub> : The minimum initial velocity on surface of earth to overcome gravitational potential energy is defined as “escape speed ve<\/sub>”
\nve<\/sub> = \\(\\sqrt{2 \\mathrm{gR}}=\\sqrt{\\frac{2 \\mathrm{GM}}{\\mathrm{R}}}\\)<\/p>\n

\u2192 Orbital velocity: Velocity of a body revolving in the orbit is called orbital velocity.
\nOrbital velocity V0<\/sub> = \\(\\sqrt{\\frac{\\mathrm{GM}}{\\mathrm{R}}}\\) \u21d2 V0<\/sub> = \\(\\sqrt{\\mathrm{gR}}\\)<\/p>\n

Note:<\/p>\n