Explore BrainMass


Gravitation: Weightlessness

Astronauts who spend long periods in outer space could be adversely affected by weightlessness. One way to simulate gravity is to shape the spaceship like a cylindrical shell that rotates, with the astronauts walking on the inside surface. Explain how this simulates gravity. Consider (a) how objects fall, (b) the force we

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

Falling objects Air resistance Gravity Gravitational force

Part 1, each question should be answered separately. 7. Suppose you are in a barrel going over Niagara Falls and during the fall you drop an apple inside the barrel. Would the apple appear to move toward the top of the barrel or toward the bottom, or would it remain stationary within the barrel? 10. (a) Imagine that Charlo

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

minimum height 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?


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

Hailstone Physics

Please see attached file for full problem description. A spherical hailstone falls freely from rest under gravity. It initially has radius a. As it falls its volume increases through condensation at a rate equal to times the surface area, where is a constant. (a) Show that after a time t its radius r is equal to a+ t.

Tension 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

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.

True/False: velocity, motion, gravity, mass

The average velocity of a car traveling with a constant acceleration during a certain time interval is equal to the mean of the velocities at the beginning and end of that time interval. True False Free-fall is the motion of an object subject only to the influence of gravity. True False M

Molecules Escaping Earth's Gravity: Example Problem

Escape velocity near Earth's surface is 11 km/s which means that a particle near Earth's surface traveling faster than about 11 km/s will have enough kinetic energy to completely escape from Earth's gravitational pull. Molecules in the upper atmosphere that are moving faster than this will therefore escape if they do not suffer

Molecules escaping Earth's gravity.

Escape velocity near Earth's surface is 11 km/s which means that a particle near Earth's surface traveling faster than about 11 km/s will have enough kinetic energy to completely escape from Earth's gravitational pull. Molecules in the upper atmosphere that are moving faster than this will therefore escape if they do not suffer

Reaction on point A

In problem 16.3(a), A 60-lb uniform thin panel is placed in a truck with end A resting on a rough hoirzontal surface and end B supported by a smooth vertical surface. Knowing that the deceleration of the truck is 12 ft/s^2, determine the reactions at ends A is a. 70.03 lb b. 60.30 lb c. 90.70 lb d. 80.71 lb

Net Force Gravity

An equilateral triangle L = 11.5 m on a side has an m1= 1.13 kg mass at one corner, a m2 = 2.23 kg mass at another corner and a m3 = 3.39 kg mass at the third corner, as shown in the figure below. Figure is attached. Calculate the magnitude of the net force acting on the 1.13 kg mass. Calculate the direction of the net fo

projectile motion on the surface of the moon

A projectile is launched vertically from the surface of the Moon with an initial speed of 1400 m/s. At what altitude is the projectile's speed three fifths its initial value? Show all your work and calculations and the final answer.

Average net force on the man during landing on the ground

A 75 kg man just before contact with the ground has a speed of 6.4 m/s. (a.) In a stiff-legged landing he comes to a halt in 2.0 ms. What is the average net force that acts on him during this time. (b.) When he bends his knees, he comes to a halt in 0.10 s. What is the average net force now? (c.) During the landing,

Motion under gravity explained

A 2-kg object is thrown upwards with an initial velocity of +20 m/s and travels in free-fall motion. a. Diagram the forces acting upon the ball after it leaves the hand of the thrower. As in all free-body diagrams, label every force according to type. b. Calculate the acceleration of the ball. c. Calculate the speed of the b