Wednesday

July 1, 2015

July 1, 2015

Number of results: 76,862

**phisecs**

water is moving with a speed of 5 m/s through a pip with a cross-sectional area of 4cm^2 . the water gradual descends 10 m as the pipe cross-sectional area increases 8cm^2 . if the pressure at the upper level is 1.5*10^5 , the pressure at the lower level is ?
*April 22, 2014 by w*

**physics**

Consider the following mass distribution, where x- and y- coordinates are given in meters: 5.0 kg at (0.0, 0.0) m, 4.0 kg at (0.0, 7.0) m, and 7.0 kg at (5.0, 0.0) m. Where should a fourth object of 8.0 kg be placed so that the center of gravity of the four- object arrangement...
*November 11, 2012 by Anonymous*

**Physics**

Two charges are located along the x-axis. One has a charge of 6.3 μC, and the second has a charge of −3.4 μC. If the electrical potential energy associated with the pair of charges is −0.043 J,what is the distance between the charges? The value of the ...
*March 6, 2012 by Willow*

**Physics**

1. Find the pressure exerted on the ground (in psi) by a 250 lb person who is sitting on a chair whose 4 legs touch the ground with area of '1 by2' each. 2.a)A large 50 kg crate is at rest on level ground. Two people push on the crate. One pushes north with 200 N while the ...
*July 14, 2012 by Fix30*

**physics**

A 35kg lawnmower starts from rest. Its pushed with a force of 127N at an angle 40 degrees below horizontal. After 12s it reaches speed of 0.37m/s. Find acceleration and force of friction. Attempts: Well I figured out Fnormal=343 my multiplying mass by gravity and assuming as ...
*November 30, 2014 by jamie*

**physics**

A hockey puck is given an initial speed of 19 m/s on a frozen pond. The puck remains on the ice and slides 113 m before coming to rest. The acceleration of gravity is 9.8 m/s 2 . What is the coeﬃcient of friction between the puck and the ice?
*December 5, 2011 by khjkjk*

**Physics**

An elevator cable breaks when a 950 kg elevator is 23 m above a huge spring (k = 2.3×105 N/m) at the bottom of the shaft. (a)Calculate the work done by gravity on the elevator before it hits the spring. (b) Calculate the speed of the elevator just before striking the spring. (...
*November 17, 2010 by Sasha*

**Physics **

A falling toy, mass 10.0 kg experiences an upward force due to air friction of 40.0 N. Find the acceleration of the toy. I honestly have no idea how to solve this question. Could someone please help me? :(
*June 19, 2015 by Austin*

**physics**

An object is released from rest on a planet that has no atmosphere. The object falls freely for 5.02 m in the ﬁrst second. What is the magnitude of the acceleration due to gravity on the planet? Answer in units of m/s can someone help me please? i tried doing this -5....
*September 13, 2012 by michelle*

**Physics**

Alexis Farias realizes her dream to play golf on the moon. She hits a golf ball with an initial velocity of 23.5m/s at an angle of 35.0 degrees above the horizontal. The acceleration due to gravity on the moon is 1.67m/s^2. A). How long is the golf ball in the air? B). How far...
*October 31, 2014 by Taylor*

**physcial science**

How do I calculate the orbital velocity of a satellite that is 400 miles above the earth? Set the centripetal acceleration V^2/(R+h) equal to the gravitational acceleration, g * [R/(R+h)]^2 Then solve for V R is the earth's radius and h is the 400 mile height. g is the ...
*June 25, 2007 by dave*

**physics**

An astronaut visits a moon of Saturn, and decides to measure the accel. of gravity. He ties a rock (m=2 kg) to a rope (1.25 m), pulls the rock back 10 degrees, and releases it into simple harmonic motion. What is the accel due to gravity on the moon? (*I have no idea where to ...
*February 1, 2015 by Alexis*

**PHYSICS (CHECK WORK)**

Can somebody please check my work. I got part a right, but my answer for part b is wrong. (a) Calculate the absolute pressure at the bottom of a fresh-water lake at a depth of 25.6 m. Assume the density of the water is 1.00 103 kg/m3 and the air above is at a pressure of 101.3...
*November 7, 2012 by Amy*

**Chemistry**

If the column of water in the water bormeter rose to a height of 35 feet, what would the atmospheric pressure be in mm Hg?
*October 21, 2008 by Dan*

**chemistry**

what pressure (in atm) is exerted by a column of mercury 1.4O high? The density of mercury is 13.5951 g/cm3.
*June 18, 2010 by Alex*

**science**

Which of the following is the MOST destructive force associated with tornadoes? a) The destructive pressure of the high winds associated with the tornado. b) The explosive pressure difference between the inside of a home and the lower pressure outside due to the tornado. c) ...
*August 26, 2010 by carl bennett*

**physics**

When a force is applied to an object with mass equal to the standard kilogram, the acceleration of the mass is 3.25 m/s2. When the same magnitude force is applied to another object, the acceleration is 2. 75 m/s2. What is the mass of the object? What would the second object's ...
*June 14, 2010 by Sarah*

**Physics**

The front 1.20 m of a 1,350-kg car is designed as a "crumple zone" that collapses to absorb the shock of a collision. (a) If a car traveling 22.0 m/s stops uniformly in 1.20 m, how long does the collision last? s (b) What is the magnitude of the average force on the car? N (c...
*October 4, 2011 by Allie*

**Algebra**

2. The following formula relates three quantities: Force (F), mass (m), and acceleration (a). F = ma a. Solve this equation for a. b. If the force is F = –25 units and the mass is m = 10 units, find the acceleration, a. c. If the force is F = 25 units and the acceleration is a...
*November 12, 2013 by Anonymous*

**chemistry**

By how much will the vapor pressure of water decrease if a solution at 40.0°C is produced by dissolving 16.0212 g of K3PO4 (formula mass = 212.30 g/mol) with 40.8480 g of water. The vapor pressure of pure water at this temperature is 55.30 mmHg. If the solute is ionic, assume ...
*February 21, 2014 by kat*

**physics**

Suppose that on earth you can throw a ball vertically upward a distance of 2.39 m. Given that the acceleration of gravity on Mars is 3.80 m/s2, how high could you throw a ball on Mars? (Take the y-axis in the vertical direction, and assume that the location of your hand is at ...
*January 31, 2013 by octavia*

**physics**

(time given is the total time in the air, up and down) During a baseball game, a batter hits a high pop-up. If the ball remains in the air for 4.84 s, how high does it rise? The acceleration of gravity is 9.8 m/s2 . Answer in units of m
*September 29, 2013 by mary*

**physics**

(time given is the total time in the air, up and down) During a baseball game, a batter hits a high pop-up. If the ball remains in the air for 4.84 s, how high does it rise? The acceleration of gravity is 9.8 m/s2 . Answer in units of m
*September 29, 2013 by mary*

**physics**

(time given is the total time in the air, up and down) During a baseball game, a batter hits a high pop-up. If the ball remains in the air for 4.84 s, how high does it rise? The acceleration of gravity is 9.8 m/s2 . Answer in units of m
*September 29, 2013 by mary*

**science**

A worker drags a crate across a factory floor by pulling on a rope tiedto the crate. The worker exerts a force of 450 N on the rope, which is inclined at 38 degrees to the horizontal and teh floor exerts a horizontal force of 125 N that opposes the motion. Calculate the ...
*November 12, 2006 by Chris*

**calculus**

use a(t) = -32 ft per second squared as the acceleration due to gravity.An object is thrown vertically downward from the top of a 480-ft building with an initial velocity of 64 feet per second. With what velocity does the object hit the ground? This type of problem always ...
*February 21, 2010 by sammi*

**Physics**

1. Gunter, the weightlifter, can lift a 230.0 kg barbell overhead on Earth. The acceleration due to gravity on the sun is 274 m/s2. 2. a. Would the barbells be heavier on the sun or on the Earth. heavier on the sun b. How much (in Newtons) would the barbells weigh on the sun...
*November 1, 2010 by Micah*

**Chemistry**

If 0.823g of an unknown gas occupies a volume of 702.0 mL at 38.9 deg. Celsius, and 726.2 mm Hg pressure, what is the molar mass of the gas? (pressure has already been corrected for water vapor pressure)
*April 17, 2011 by Carla*

**Physics**

A man of mass 75 kg lies on a bed of 10,000 nails. The tip of each nail has an area of 1.0 square millimeter. What pressure does the man experience? [g=10 N/kg]
*April 12, 2014 by Erin*

**Chemistry**

I am trying to determine which protein (in a given list) will stick most tightly to a cation exchange column at pH 7. I am unsure how to go about solving this.. We are given molecular weight, isoelectic point, and number of subunits for each protein. Where should I begin?
*January 31, 2013 by Lisa*

**Chemistry**

I am trying to determine which protein (in a given list) will stick most tightly to a cation exchange column at pH 7. I am unsure how to go about solving this.. We are given molecular weight, isoelectic point, and number of subunits for each protein. Where should I begin?
*January 31, 2013 by Lisa*

**Chemistry**

A closed container is filled with oxygen. The pressure in the container is 435kPa . What is the pressure in millimeters of mercury? (i know that 1atm=760mm Hg=101,325 Pa) How do I use this to solve for the question? so: 435kPa*101,325=44,076,375Pa, & O2 = 32g/mol & you must ...
*October 20, 2007 by leo*

**PSY210 APPENDIX G**

According to Sternberg, a person can experience eight general types of love. In the following table, a type of love as identified by Sternberg is in the left column. In the center column, write the combination of components that type of love demonstrates (intimacy, passion, or...
*October 19, 2009 by LISA*

**Chemistry**

A column of mercury in a barometer is 767.3 mm Hg high. Note, that in order for the pressures to be equal, density and height of a column are inversely proportional, therefore, (den1)(h1)=(den2)(h2). The density of mercury is 13.6 g/mL and the density of water is 1.00g/mL. a) ...
*April 16, 2014 by Carly*

**Chem**

Co2(g) ---> CO2(l) + heat This equation was given to me and asked why high pressure was needed to keep carbon dioxide in the liquid state. With the information given; I don't exactly know how to answer the question. How do you increase the pressure of a liquid. For gases ...
*July 27, 2009 by Lena*

**scienceWhich of the following is a term used to de**

Which of the following is a term used to describe a body's resistance to a change in motion? A. inertia B. acceleration c. gravity D. Mass
*February 4, 2014 by Anonymous*

**physics**

A(n) 96.1 g ball is dropped from a height of 59.1 cm above a spring of negligible mass.The ball compresses the spring to a maximum displacement of 4.75403 cm. The acceleration of gravity is 9.8 m/s^2. Calculate the spring force constant k. Answer in units of N/
*March 19, 2013 by Anonymous*

**physics**

A motorboat travels due north at a steady speed of 3.0 m/s through calm water in which there is no current. The boat then enters an area of water in which a steady current flows at 2.0 m/s in a southwest direction, as shown in the next picture. Both the engine power and the ...
*August 16, 2012 by jhon*

**Physics help please**

A 13.2 gm bullet is fired into a 12.0 kg wood block that is at rest on a wood table. The block, with the embedded bullet, slides 5.00 cm across the table. Assuming that the local acceleration due to gravity is 9.80m/s2 and that the coefficient of kinetic friction between the ...
*October 26, 2011 by Iamdumb*

**chemistry**

"Newton's law tells us that Force= Mass x Acceleration. We also know that Energy = Force x Distance and Pressure= Force/Area. Using these relationships and table I-1 [I'll type it out], derive (do math stuff) the dimensions of newtons, joules, and pascals in terms of the ...
*September 13, 2006 by Jenn*

**physics**

A mass of 20 kg on a plane inclined at 40 degrees. A string attached to that mass goes up the plane, passed over a pullley and is attached to mass of 30 kg that hangs verticalyy. a) find the acceleration and it's dirction b) the tension in the string. Assume no friction. I ...
*November 20, 2006 by Benji*

**Trigonometry**

The advertisement for a new shoe promises runners less slip. The coefficient of friction (μ) between concrete and a new material used in the sole of this shoe is 1.5. The force of friction that causes slip is equal to mg sinθ, where m is a runner’s mass and g is the ...
*June 24, 2010 by Mary*

**math**

What do the lines making a circle around the low-pressure area indicate? 1.The values cannot be added because one is measuring area and the other is measuring volume. 2.The values can be added without making a conversion of units because they both measure area. * 3.The values ...
*January 15, 2015 by king*

**Physics**

An ideal gas at 6.0°C and a pressure of 1.92 105 Pa occupies a volume of 2.10 m3. (a) How many moles of gas are present? moles (b) If the volume is raised to 4.60 m3 and temperature raised to 30.5°C, what will be the pressure of the gas? Pa I used the formula n= (pv)/rt which ...
*April 20, 2008 by Johnson*

**Physics**

A model airplane of mass 0.9 kg is attached to a horizontal string and flies in a horizontal circle of radius 5.2 m, making 1.2 revolutions every 8 s. (The weight of the plane is balanced by the upward “lift” force of the air on the wings of the plane.) The accelaration due to...
*December 21, 2010 by Aaron*

**Physics**

A model airplane of mass 0.9 kg is attached to a horizontal string and flies in a horizontal circle of radius 5.2 m, making 1.2 revolutions every 8 s. (The weight of the plane is balanced by the upward “lift” force of the air on the wings of the plane.) The accelaration due to...
*December 21, 2010 by Aaron*

**physics**

What pressure (atm) is exerted by a column of ethanol 65.0 cm high? The density of ethanol is 0.789 g/cm3 and 9.8m/s2 as your gravitational
*October 17, 2010 by chris*

**mila**

Determine the time it takes for a satellite to orbit the Saturn in a circular "near-Saturn" orbit. A "near-Saturn" orbit is at a height above the surface of the Saturn that is very small compared to the radius of the Saturn. [Hint: You may take the acceleration due to gravity ...
*July 13, 2013 by perat*

**physic**

Determine the time it takes for a satellite to orbit the Saturn in a circular "near-Saturn" orbit. A "near-Saturn" orbit is at a height above the surface of the Saturn that is very small compared to the radius of the Saturn. [Hint: You may take the acceleration due to gravity ...
*July 13, 2013 by jasika*

**physics**

A ruler stands vertically against a wall. It is given a tiny impulse at such that it starts falling down under the influence of gravity. You can consider that the initial angular velocity is very small so that . The ruler has mass 250 g and length 30 cm. Use m/s for the ...
*December 6, 2013 by juanpro*

**physics**

Winds in a certain city can attain sustained speeds of 45 m/s when the jet stream descends during spring. Approximately what force does a roof with an area of 200 m^2 experience due to the Bernoulli effect, assuming air flow is completely laminar? Density of air is 1.14 kg/m^3...
*November 9, 2010 by Anonymous*

**physics**

Ok, so I know the different kinds of forces (applied, normal, gravity, parellel, and friction). And I know how to sub in other numbers for those forces ( for example, Parallel force is equal to mass times gravity times sine theta). I also know the "base" equation (a=net force/...
*November 15, 2008 by Julia*

**physics**

A home run is hit such a way that the baseball just clears a wall 26 m high located 118 m from home plate. The ball is hit at an angle of 37 ◦ to the horizontal, and air resistance is negligible. Assume the ball is hit at a height of 1 m above the ground. What is the ...
*October 6, 2014 by natalie*

**Physics**

A ﬁreman, 34.9 m away from a burning building, directs a stream jet of water from a ground level ﬁre hose at an angle of 44.2◦ above the horizontal. If the speed of the stream as it leaves the hose is 60.5 m/s, at what height will the stream of water strike...
*October 19, 2013 by Sarah*

**Physics**

A tennis ball is dropped from 1.41m above the ground. It rebounds to a height of 0.932 m.The acceleration of gravity is 9.8 m/s2 .(a)With what velocity does it hit the ground?(Let down be negative.) Answer in units of m/s. (b)With what velocity does it leave the ground? Answer...
*September 12, 2009 by sandhu*

**math**

the trajectory, of the projectile satisfies the following equation,wher g is the acceleration due to gravity, y=mx-g/2v^2(1+m^2)x^2 where y as the vertical rise, and x asthe horizontal component of the displacement. A football is kicked with initial velocity v= 80 fett per ...
*October 20, 2013 by walter hughes *

**Math**

When you scuba dive, the added pressure due to the water varies directly with your depth. At 20 feet, the added pressure is about 9 pounds per square inch. a) If an amateur diver can safely stand an added pressure of 30 (psi), how deep could he dive? b) A sunken submarine lies...
*November 4, 2012 by M*

**physics**

A reel has radius R and moment of inertia I. The reel is positioned at the top of a slope and a block is also on the slope with some angle theta. One end of the block of mass m is connected to a spring of force constant k, and the other end is fastened to a cord wrapped around...
*March 31, 2009 by mightymouse*

**Physics**

A 2500kg car is travelling due west at 30m/s when the brakes are applied, exerting a force of 5000 N [E]. What is the car's acceleration due to the braking?
*March 2, 2008 by Marty*

**Physics**

A curve of radius 60m is banked so that a car traveling with uniform speed 70km/hr can round the curve without relying on friction to keep it from slipping to its left or right. The acceleration of gravity is 9.8m/s^2. What the the Angle of the curve? im using a=v^2/r, but ...
*September 17, 2006 by puff puff*

**Physics**

Calculate the effective value of g, the acceleration of gravity, at 6400m , above the Earth's surface. Calculate the effective value of g , the acceleration of gravity, at 6200km , above the Earth's surface
*October 2, 2009 by Lea*

**physics**

1 The specific heat of a substance at its boiling point or melting point Is 0 Is infinity Is negative lies between 0 and 1 2 A unit mass of solid converted to liquid at its melting point. Heat is required for this process is Specific heat Latent heat of vaporization Latent ...
*April 12, 2015 by promise*

**physics**

1 The specific heat of a substance at its boiling point or melting point Is 0 Is infinity Is negative lies between 0 and 1 2 A unit mass of solid converted to liquid at its melting point. Heat is required for this process is Specific heat Latent heat of vaporization Latent ...
*April 17, 2015 by solomon*

**physics**

A(n) 96.1 g ball is dropped from a height of59.1 cm above a spring of negligible mass.The ball compresses the spring to a maximum displacement of 4.75403 cm.The acceleration of gravity is 9.8m/s^2. Calculate the spring force constant k. Answer in units of N/m
*March 18, 2013 by Anonymous*

**physics**

Calculate the density of the balls in this area. Each ball has a mass of 1 kg. Estimate the area taken up by the whole structure by looking in the Parameters Palette for the diameter of the balls and multiplying this by the number of balls on each side. Record below the total ...
*November 13, 2011 by KAy*

**Chemistry**

How many moles of gas must be forced into a 3.5 L ball to give it a gauge pressure of 9.4 psi at 25 degrees C? The gauge pressure is relative to atmospheric pressure. Assume that atmospheric pressure is 14.7 psi so that the total pressure in the ball is 24.1 psi Ok so I'm ...
*October 18, 2011 by Monique *

**Calc**

A ball is thrown straight up from the top of a 200 foot building with an initial velocity of 40feet/second. acceleration due to gravity is -32feet/second. a) find a formula for the height of the ball at time t. b) how high does the ball rise before it begins to fall c) when ...
*May 5, 2015 by Jason*

**Physics HELP!**

A simple pendulum consists of a small object of mass 7.40 kg hanging at the end of a 2.10 m long light string that is connected to a pivot point. (a) Calculate the magnitude of the torque (due to the force of gravity) about this pivot point when the string makes a 3.00° angle ...
*November 7, 2012 by Brad*

**physics**

A simple pendulum consists of a small object of mass 3.20 kg hanging at the end of a 3.70 m long light string that is connected to a pivot point. (a) Calculate the magnitude of the torque (due to the force of gravity) about this pivot point when the string makes a 7.00° angle ...
*November 11, 2012 by Anonymous*

**Physics**

A box of mass 1kg is placed on a table and is connected to a hanging mass m by a string strung over a pulley. If the coefficient of kinetic friction between the box and the table is .3 and the box slides at a constant speed of .5m/s what is the weight of the hanging mass? ...
*November 14, 2007 by Andrea*

**physics**

A 20 kg mass is allowed to accelerate down a frictionless 15° ramp. a. Determine the value of the x-component of the force gravity. b. What is the acceleration of the block down the ramp. c. How long will it take for the block to slide 30.0m?
*January 18, 2012 by Anonymous*

**calculus**

A circular swimming pool has a diameter of 14 m, the sides are 4 m high, and the depth of the water is 3.5 m. (The acceleration due to gravity is 9.8 and the density of water is 1000 .) How much work (in Joules) is required to: (a) pump all of the water over the side? (b) pump...
*February 22, 2013 by Anonymous*

**Physics**

Mercury has a density about 13.6 times that of water. How high could you raise a column of mercury by increasing pressure to 8.2 kPa?
*April 6, 2010 by Plaster*

**chemistry**

what pressure (atm) is exerted by a column of ethanol 86.0 cm high? the density of ethanol is 0.789 g/cm3 and 9.8 m/s2 as your gravitational constant.
*June 29, 2011 by cindy*

**chemistry**

what pressure (atm) is exerted by a column of ethanol 86.0 cm high? the density of ethanol is 0.789 g/cm3 and 9.8 m/s2 as your gravitational constant.
*June 29, 2011 by cindy*

**chem**

What pressure (atm) is exerted by a column of ethanol 86.0 cm high. The density of ethanol is 0.789 g/cm3 and 9.8 m/s2 as your gravitational constant.
*July 6, 2011 by Tim*

**chem**

What pressure (atm) is exerted by a column of ethanol 86.0 cm high. The density of ethanol is 0.789 g/cm3 and 9.8 m/s2 as your gravitational constant.
*July 6, 2011 by Carol*

**chemistry**

What pressure (atm) is exerted by a column of ethanol 49.0 cm high? The density of ethanol is 0.789 g/cm3 and 9.8m/s2 as your gravitational constant.
*October 17, 2011 by james*

**Chemistry**

What pressure (atm) is exerted by a column of ethanol 49.0 cm high? The density of ethanol is 0.789 g/cm3 and 9.8m/s2 as your gravitational constant.
*October 17, 2011 by Sven*

**Chemisrry**

If the specific gravity of E85 gasohol is 0.801' what is the mass of 1.00 gallon of th E85 fuel. Given 1 gallon = 3.75 liters
*August 30, 2011 by Monique*

**science**

How to find the magnitude and direction of acceleration given the force and mass which are: F= 5.0 N , 20 N M= 3.0 kg How to draw the diagram for this problem? 5.0N ← 3.0 kg → 20 N
*August 19, 2009 by Amberina*

**physics**

A 4.2 kg mass undergoes an acceleration given by ~a = ax ˆı + ay ˆ , where ax = 0.6 m/s 2 and ay = 4.8 m/s 2 . Find the magnitude of the resultant force. Answer in units of N
*October 12, 2011 by Anonymous*

**physics**

Given x(t) = xm cos 2ðt/T for a spring with constant k and attached mass m sketch as a function of t, (a) the displacement x, (b) the velocity v, (c) the acceleration.
*February 22, 2012 by Noel*

**Physics**

A helicopter of mass M and weight ,W,rises with vertical acceleration, a, due to the upward thrust ,u, generated by its rotor.The crew and passengers of total mass ,m, and total weight,w, exert a combined force R on the floor of the helicopter.Write an equation for the motion ...
*April 18, 2013 by Jaden K Hove*

**physics**

A weight (with a mass of 71 kg) is suspended from a point near the right-hand end of a uniform boom with a mass of 51 kg . To support the uniform boom a cable runs from this same point to a wall (the left-hand vertical coordinate y=7 x=6) and by a pivot on the same wall at an ...
*November 7, 2011 by PHYSICS HELP!!!!*

**Science**

Find the density and specific gravity of the following (a) SO2 at 700F and 1 atm (b) Mixture of 10 mole% CH4 and 90 mole% argon at 5400C and 28.9 inch Hg (c) Air containing 0.045 lbm H2O per pound mass of dry air at 2000F and 29.7 in Hg absolute pressure
*March 26, 2015 by Man Singh Chouhan*

**physics**

A model airplane of mass 0.7 kg is attached to a horizontal string and ﬂies in a horizontal circle of radius 5.6 m, making 1.6 revolutions every 7 s. (The weight of the plane is balanced by the upward “lift” force of the air on the wings of the plane.) The accelaration ...
*December 10, 2011 by tanya*

**physics**

A model airplane of mass 1.5 kg is attached to a horizontal string and ﬂies in a horizontal circle of radius 5.8 m, making 2 revolutions every 8 s. (The weight of the plane is balanced by the upward “lift” force of the air on the wings of the plane.) The accelaration ...
*November 25, 2012 by James*

**physics**

At some instant the velocity components of an electron moving between two charged parallel plates are vx = 1.5 × 105 m/s and vy = 3.0 × 103 m/s. Suppose the electric field between the plates is given by In unit-vector notation, what are (a) the electron's acceleration in that ...
*January 26, 2011 by trisha*

**Physics**

In Larry Niven’s science fiction novel Ringworld, a ring of material of radius 1.54 × 1011 m rotates about a star with a ro- tational speed of 1.38 × 106 m/s. The inhab- itants of this ring world experience a normal contact force ~n. Acting alone, this normal force would ...
*November 17, 2012 by helpplz*

**Chem**

I stuck on this prob. Can you help me to do this? 10.00 mL of a solution containing 0.20 M NaCl and 0.25 M AlCl3 is introduced into a cation exchange column. How many moles of hydronium ions will be released by the column?
*October 22, 2010 by Kim*

**physics--HELP**

a giant robot tosses a ball up, from a height of 80 meters, with an initial velocity of Vo = 60 m/s, use 10 m/s^2 as the acceleration due to gravity. what will be the minimum velocity of the ball and when and where will that occur? [i don't know how you would find that.] what ...
*October 9, 2007 by jel*

**physics**

A diagram shows two cylinders containing two pistonsA and B. The two cylinders are connected with a tube containing a fluid. The system is similar to the hydraulic braking system of a car. A man pushes down on piston A while piston B has a 10kg mass sitting on it. The surface ...
*April 26, 2014 by Haiano*

**physics**

Three blocks are in contact with each other on a frictionless horizontal surface. A 696 N horizontal force is applied to the block with mass of 4.7 kg as shown in the ﬁgure below. The acceleration of gravity is 9.8 m/s 2 . 4.7 kg 5.5 kg 7.1 kg F a) What is the net force...
*October 19, 2012 by Anonymous*

**CHEMISTRY**

*Specific Gravity A cylinder of plastic is 100 mm long and 50 mm in diameter. It has a mass of 1 kg. Determine its specific gravity and indicate whether it would float or sink in water . PLLEEEEEEEEEEEASE
*July 3, 2013 by Myka*

**physics**

Whenever two Apollo astronauts were on the surface of the Moon, a third astronaut orbited the Moon. Assume the orbit to be circular and 720 km above the surface of the Moon, where the acceleration due to gravity is 0.839 m/s2. The radius of the Moon is 1.70 106 m. (a) ...
*October 22, 2011 by carlton*

**physics**

Whenever two Apollo astronauts were on the surface of the Moon, a third astronaut orbited the Moon. Assume the orbit to be circular and 720 km above the surface of the Moon, where the acceleration due to gravity is 0.839 m/s2. The radius of the Moon is 1.70 106 m. (a) ...
*October 24, 2011 by carlton*

**physics**

A rocket is fired in deep space, where gravity is negligible. In the first second it ejects 1/160 of its mass as exhaust gas and has an acceleration of 15.1 m/s^2.What is the speed v_gas of the exhaust gas relative to the rocket?
*November 14, 2011 by paul*

**NEED HELP PHYSICS!!!**

An airplane is flying in a horizontal circle at a speed of 117 m/s. The pilot does not want his centrifugal acceleration to exceed 6.8g (that is, to be more than 6.8 times the acceleration of gravity). What is the minimum radius (in meters) of the circular path? PLEASE LEAVE ...
*April 7, 2015 by baz*

**Physics**

An acrobat hangs by his hands from the mid- dle of a tightly stretched horizontal wire so that the angle between the wire and the hori- zontal is 12.5◦. If the acrobat’s mass is 88.8 kg, what is the tension in the wire? The acceleration of gravity is 9.8 m/s2. Answer in ...
*November 12, 2009 by Letisha*