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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.

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?

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.

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

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

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

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

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.

Two problems: Dimensional analysis and Flow of fluid in pipe.

Please see attached file for full problem description. 1. The thickness h of a puddle of water on a waxy surface depends on the density ρ of the liquid, the surface tension γ (SI units: N/m) and another physically which is gravity, g. Use dimensional analysis to find a relationship between the thickness and the other 3 vari

Astrophysics: Friction, Potential Energy, and Kinetic Energy

1. A spring with k = 40.0 N/m is at the base of a frictionless 30.0° inclined plane. A 0.50-kg object is pressed against the spring, compressing it 0.20m from its equilibrium position. The object is then released. If the object is not attached to the spring, how far up the incline does it travel before coming to rest and then

moment and tension

A 66-kg sign hung centered from a uniform rod of mass 8.2 kg and length 2.3m. At one end the rod is attached to the wall by a pivot, ans the other end it's supported by a cable that can withstand a maximum tension of 800N. what is the minimum height h above the pivot for anchoring the cable to the wall?

physics

Could you please provide the answers and workings out to the following physics problems. explain exactly how you came up with answer, provide a graph/drawing where needed for better understanding of the answer. Please see attachment. 1. When the net force that acts on a hockey puck is 10 N, the puck accelerates at a rate

tention in the line when lifting the gold out of water

A Scottish physics professor is fishing in Loch Ness and hooks an ancient gold artifact. The density of gold is 19300 kg/m3 and seawater is 1035 kg/m3. While he is pulling up the treasure, the tension in his fishing line is 120N. What will be the tension in his line when he lifts the object out of the water?

Spring Compression

A small block of mass 0.09 kg is placed against a compressed spring at the bottom of a frictionless track that slopes upward at an angle of 40* above the horizontal. The spring has k=640 N/m and negligible mass. When the spring is released, the block travels a maximum distance of 1.8 m along the track before sliding back down. B

Vertical and Horizontal Force of a Dropped Bowling Ball

General clarifications to the problem statement: 1. The bowling ball is 8 inches in diameter 2. I only need the minimum horizontal force needed to move the ball into the horizontal pipe 3. The force acts at the center of mass of the ball when the ball reaches 30 ft in vertical drop Please see attached. A 10 lb bowling

Earth, stars, and humanity's search for extraterrestrial intelligence.

Hello I'm of need with patrs A, C & D. Please make them at least 400 words each. I have done B, E & F. but after this help I'll also need to make a 20-25 slide powerponit which I will do. a. Describe the properties of life on Earth. (400 words) b. Examine the possibilities of extraterrestrial life in our solar system. Wh

Center of Mass of a Pyramid

Find the center of mass of a pyramid (square base) without using calculus. I need as many different solutions as possible (my professor says he found 13 different algebraic methods).

Acceleration due to gravity measured with wire and ball

To measure the acceleration due to gravity on a distant planet, an astronaut hangs a 0.070 kg ball from the end of a wire. The wire has a length of 1.5 m and a linear density of 3.1 10-4 kg/m. Using electronic equipment, the astronaut measures the time for a transverse pulse to travel the length of the wire and obtains a value

Ideal spring and simple harmonic motion

To measure the static friction coefficient between a 1.9 kg block and a vertical wall, the setup shown in the drawing is used. A spring (spring constant = 418 N/m) is attached to the block. Someone pushes on the end of the spring in a direction perpendicular to the wall until the block does not slip downward. If the spring i

Acceleration of Gravity/Divergence Theorem

Acceleration of Gravity. See attached file for full problem description. Find the acceleration of gravity g for the following mass distribution. The mass distribution consists of an infinitely long "wire" of radius a running along the z axis, surrounded by empty space then by a hollow cylinder with inner radius b and outer ra

Spacing of Rails/Removal of Heat

1. Segments of 12mt long steel rails are laid end to end when the temperature is -12 degree C. A space is left between rail segments to allow for thermal expansion. a. If they are to just touch when the temp is 33degree C, the spacing is --------- 2. A freezer has a coefficient of performance of 2.40 and can convert 1.80 k

Disk and a hoop

A disk and a hoop of the same mass and radius are released at the same time at the top of an inclined plane. Which object reaches the bottom of the incline first? The hoop The disk Both reach the bottom at the same time. It depends on the angle of inclination.