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    Gravity

    Gravity is a natural phenomenon in which all physical bodies are attracted to each other. It is commonly witnessed as the agent that gives weight to objects with mass and causes them to fall to the ground when dropped. It is also the same agent that allows your feet to stay on the ground.
    Gravity is one four fundamental interactions of nature. The other three include electromagnetism, nuclear strong force and weak force. Gravitational force is the only fundamental force that affects all matter. This force is proportional to the masses of the interacting bodies.

    The cosmological perspective of gravitation says it causes dispersed matter to coalesce matter to remain intact. This accounts for the existence of planets, galaxies, stars and most macroscopic objects in the universe. Gravity is also responsible for keeping the Planets in orbit around the sun.
    Gravity is what keeps the moon in its orbit around the Earth. The moons gravitational pull is what influences the tides. This occurs by natural convection by the density gradient.

    Every planet is surrounded by its own unique gravitational field. The gravitational field is numerically equal to the acceleration of objects under its influence. Earth’s acceleration due to gravity is 9.80665 m/s2 or 32.1740 ft/s2. This is ignoring air resistance.

    © BrainMass Inc. brainmass.com September 21, 2019, 11:46 am ad1c9bdddf

    Lorentz transform of the components of the velocity

    A photon moves at an angle θ with respect to the x' axis in frame S'. Frame S' moves at speed v with respect to frame S (along the x' axis). Calculate the components of the photon's velocity in S, and verify that the speed is c.

    Gravitational time dilation

    Someone moves to the top of the World Trade Center in New York and moves back to the ground floor after one year according to a clock located at the ground floor. By how much did this person age?

    Gravitational waves: Computing full metric

    Write down the full metric (flat metric plus the perturbation) which represents a sinusoidal wave of frequency 200Hz traveling in the z direction with the cross polarization. The maximum strain of 10^-21 occurs when t=0.

    Converging Lens with Focal Length

    See the attached file. 1. A converging lens with a focal length of 3.1 cm is used to image an object which is 3.4 cm away from the lens. How far from the lens is the image? 2. A light beam (initially in air) strikes a substance with an index of refraction of 1.4 at an incident angle of 18.0 degrees. What is the refracted a

    Acceleration Due to Gravity, Time and Horizontal Velocity

    1. (PART ONE OF TWO): You drop a stone from a position of rest. How far will it fall vertically in the ?rst 5 s? The acceleration of gravity is 9.8 m/s. 2. ( PART TWO OF TWO): If you instead toss it horizontally at 1.6 m/s, how far will it fall vertically in the ?rst 5 s? 3. A cat chases a mouse across a 1.7 m high table.

    Archimedes' Principle

    1. A copper penny has a mass of 2.7 g. What is the buoyant force acting on this penny when dropped into water? (The answer should be 3.0 mN) 2. An iceberg (917 kg/m^3) is floating in the ocean (1,025 kg/m^3). What percentage of the total volume of the iceberg is below the surface of the water? (The answer should be 89.5%)

    Satellites and Gravity

    The only force acting on a satellite in its orbit around Earth is the force of gravity from Earth. Why does a satellite not fall down to earth? If you share your idea with reference it helps me to understand the subject more.

    Spring Constant, Length; Work Done by Gravity and Compression

    One safety mechanism used in elevators consists of a giant spring located at the bottom of the elevator shaft. In one particular shaft, the spring has a spring constant of 8.00x10^4 N/m, and the elevator car weighs 8250 N. a. Exactly 28.0 m above the spring, the resting elevator's cable snaps and the car falls to the bottom o

    Centripetal acceleration, Angular speed and Tangential speed

    1. When jumping straight down, you can be seriously injured if you land stiff-legged. One way to avoid injury is to bend your knees upon landing to reduce the force of the impact. A 80.4-kg man just before contact with the ground has a speed of 8.27 m/s. (a) In a stiff-legged landing he comes to a halt in 3.85 ms. Find the magn

    Energy and Gravity

    See attached image for picture of problem. A particle P of mass m is fastened to the end of a string with length L. The particle starts from rest, in a position where the string is taut, and the direction of the string forms an angle of 60 degrees with the vertical. In the lowest point of the circular arc, the particle P hits

    Density of Energy in a Point and Specific Gravity of Material

    Please show all the work. 1. Determine the density of energy in a point if v=15m/s and P=30N/cm2 for a liquid with ѳx=1.4(specific gravity). 2. A hollow sphere with R (exterior) = 10cm and r (interior) = 8.5cm, floats in water with 30% of its volume submerged. Determine the specific gravity of the material of the spher

    Water flow rate through an opening in a tube

    Please see attached file for the illustration. Tube B (full of air) is sealed on the top and a 16" OD opening on the bottom. B is 104.6' long. Container E (full of air) is inserted into section H and permanently fixed in place. B is inserted fully into container C. Water rises 59.6' into B. H is 45' feet of air. See Illus

    Find the gravitational force exerted by multiple objects

    Objects with masses of 170 kg and a 470 kg are separated by 0.320 m. (a) Find the net gravitational force exerted by these objects on a 70.0 kg object placed midway between them. (b) At what position (other than infinitely remote ones) can the 70.0 kg object be placed so as to experience a net force of zero? _______ m fro

    Tension on a String, Centripetal Acceleration

    4. A boy whirls a ball on a string 1.0 m long in a horizontal circle at 50 rpm. If the mass of the ball is 0.22 kg, what is the tension in the string? 5. A jetliner traveling at 600 km/h is turning in a circle of radius 2.5 km. What is its centripetal acceleration? 6. A 4.0-kg object is lifted 1.5 m. (a) How much work is d

    Motion Problems

    Please provide a detailed step by step solution to this problem. Thanks. The space shuttle orbits the Earth in a near-circular orbit at a constant speed at approximately 100 miles above the Earth's surface. If we assume that the centripetal acceleration is equal to the acceleration due to gravity at sea level (9.8 m/s2) and t

    Simple pendulum period depends on length, amplitude, gravity

    Consider an ideal pendulum consisting of a "bob" of mass m hanging from a light (massless) string of length L. The pendulum swings back and forth in simple harmonic motion (SHM). You may assume that the oscillations are small, so that the motion is "ideal" SHM. Which of the following statements are true? 1. If the string len

    Find momentum and force on an accelerating object

    An 850 kg dragster accelerates from rest to 90 km/h in 0.90 seconds. (a) What is the change in momentum of the car? kg·m/s (b) What is the average force exerted on the car? N (c) What exerts that force? the dragster inertia the track through friction gravity the motor

    Gravitation: 4 Problems

    1) The following formula represents the period of a pendulum,T. T = 2π(l/g) (a) What would be the period of a 1.8 m long pendulum on the moon's surface? The moon's mass is 7.34 1022 kg, and its radius is 1.74x10^6 m. 2) A force of 40.9 N is required to pull a 10.2 kg wooden block at a constant velocity across a smooth gla

    Insterstellar Travel and Difficulties

    Will it be possible in the future to travel to other stars ? What difficulties are there? Please use the web for suitable, supporting articles. - Provide references (do not use Wikipedia)

    Specific Gravity and Density

    What are the units of specific gravity? Assuming that the density of water is 0.997 g.mL^-1 and the specific gravity of gold is 19.28 what is the density of gold in g.mL^-1? In pounds per cubic foot? my attempt: no units for specific gravity. Density of gold in g.ml^-1 = 19.2 g/mL^-1 I have no idea how to convert to pounds p

    Magnitude of Gravitational Froce

    A 509 kg uniform solid sphere has a radius of 0.409 m. Find the magnitude of the gravitational force exerted by the sphere on a 50.9 g particle located (a) 1.48 m from the center of the sphere _______ N (b) at the surface of the sphere _______ N (c) 0.206 m from the center of the sphere _______ N

    Gravitational attraction

    Three masses are arranged on the vertices of an equilateral triangle. Find the gravitational force (magnitude and direction) on one of them according to the data given in the file. An equilateral triangle 59.0 m on a side has a m1 = 20.00 kg mass at one corner, a m2 = 35.00 kg mass at another corner, and a m3 = 115.00 kg mass

    Center of gravity

    Please see the problem at the following link: http://books.google.com/books?id=LiRLJf2m_dwC&printsec=frontcover&dq=vector+calculus+marsden#PPA481,M1 It is problem 14 on page 481 (section 7.5). Please show me how to do this problem correctly. Thank you

    The force of gravity is calculated.

    Please help with the following problems. 1. Calculate the force of gravity on a 65-kg person in the following: a. at the surface of the Earth (R=6400km) b. at twice the Earth's radius c. at four times the Earth's radius 2. Plot this gravitational force with distance. What pattern or relationship do you expect to

    Vertical motion under gravity

    Please help with the following problem. You are standing on a balcony 30 feet off the ground. You want to throw your key to someone on the ground. You throw it angled upward with initial velocity of 55 ft/sec. assume that the acceleration due to gravity is -32 ft/sec/sec. A) find the position function in terms of time, t.

    Motion under Gravity

    Two identical balls are thrown from the top of a building with the same speed. Ball (theta) above the 1 is thrown horizontally, while ball 2 is thrown at an angle horizontal. Neglecting air resistance, which ball will have the greatest speed when hitting the ground below?

    Density or Relative Density or Specific Gravity

    A 0.53 kg piece of wood floats in water but is found to sink in alcohol (specific gravity = 0.79) in which it has an apparent mass of 0.040 kg. What is the SG or density or relative density of the wood?