Friday

September 30, 2016
Number of results: 64,438

**Physics**

The instruments attached to a weather balloon have a mass of 5.2 kg. The balloon is released and exerts an upward force of 98 n on the instruments. A)what is the acceleration of the balloon and instruments? B) after the balloon has accelerated for 10s, the instruments are ...

*January 12, 2013 by Jules*

**physics12**

The instruments attached to a weather balloon have a mass of 5.1 kg. (a) The balloon is released and exerts an upward force of 102 N on the instruments. What is the acceleration of the balloon and instruments? (b) After the balloon has accelerated for 13 seconds, the ...

*December 11, 2011 by Hannah*

**physics**

the instruments attached to a weather balloon have a mass of 5.0 kg. the balloon is released and exerts an upward force of 98 N on the instruments. (a) what is the acceleration of the balloon and instruments? (answer is 9.8 m/s^2.. just dont know how to get there..) (b)after ...

*October 10, 2011 by tayler*

**physics**

the instruments attached to a weather balloon have a mass of 5.0 kg. the balloon is released and exerts an upward force of 98 N on the instruments. (a) what is the acceleration of the balloon and instruments? (answer is 9.8 m/s^2.. just dont know how to get there..) (b)after ...

*October 10, 2011 by tayler*

**Physics**

A spherical hydrogen-filled balloon is used to lift a load of 5950 N (in addition to the weight of the hydrogen). Suppose the density of the air is 1.18 kg/m3. Find the minimum necessary radius for the balloon

*April 3, 2014 by Jason*

**physics**

An empty rubber balloon has a mass of 0.0100 kg. The balloon is filled with helium at a density of 0.181 kg/m3. At this density the balloon is spherical with a radius of 0.300 m. If the filled balloon is fastened to a vertical line, what is the tension in the line?

*December 20, 2010 by april*

**physics**

The instruments attached to a weather balloon in the figure below have a mass(m) of 5.0 kg. The balloon is released and exerts an upward force(F) of 92 N on the instruments.

*November 2, 2010 by eden*

**Physics**

I found the first three parts of the question but I can't figure out part d. The instruments attached to a weather balloon in the figure below have a mass(m) of 5.5 kg. The balloon is released and exerts an upward force(F) of 109 N on the instruments. (a) What is the ...

*January 3, 2010 by Sasha*

**physics**

an empty rubber balloon has mass 0.0120kg, the balloon is filled with helium of density 0.181 kg/m^3. the balloon is spherical w/ radius 0.500m. if the balloon is ties to a vertical string, what is thw tension in the string? density of air 1.29 kg/m^3

*December 15, 2012 by Helen*

**AP Chemistry**

The buoyant force on a balloon is equal to the mass of air it displaces. The gravitational force on the balloon is equal to the sum of the masses of the balloon, the gas it contains, and the balloonist. If the balloon and balloonist together weight 175 kg, what would the ...

*October 11, 2010 by Emma*

**science**

A weather balloon carries instruments that measure temperature, pressure, and humidity as it rises through the atmosphere. Suppose such a balloon has a volume of 1.2 m^3 at sea level where the pressure is 1 atm and the temperature is 20°C. When the balloon is at an altitude of...

*November 19, 2011 by Shirley*

**Physics**

The instruments attached to a balloon have a mass of 5kg. The balloon is released and exerts an upward force of 100 N. After the balloon has accelerated for 10s, the instruments are released. What is the velocity of the instruments at the moment of release?

*November 2, 2015 by Bill*

**physics**

A spherical balloon has a radius of 6.76 m and is filled with helium. How large a cargo can it lift, assuming that the skin and structure of the balloon have a mass of 950 kg? Neglect the buoyant force on the cargo volume itself.

*April 18, 2010 by Anonymous*

**Chemistry**

The buoyant force on a balloon is equal to the mass of air it displaces. The gravitational force on the balloon is equal to the sum of the masses of the balloon, the gas it contains, and the balloonist. If the balloon and balloonist together weight 175 kg, what would the ...

*October 11, 2010 by Emma*

**AP Chemistry**

The buoyant force on a balloon is equal to the mass of air it displaces. The gravitational force on the balloon is equal to the sum of the masses of the balloon, the gas it contains, and the balloonist. If the balloon and balloonist together weight 175 kg, what would the ...

*October 12, 2010 by Em*

**physical science**

A Weather balloon carries instruments that measure temperature, pressure, and humidity as it rises through the atmosphere. Suppose such a balloon has a volume of 1.2 m3 at sea level where the pressure is 1 atm and the temperature is 20oC. When the balloon is at an altitude of ...

*October 4, 2012 by maria*

**physics**

a weather balloon carries instruments that measure temperature,pressure and humidity as it rises through the atmosphere.Suppose such a balloon has a volume of 1.2 m^3 at sea level where the pressure is 1 atm and the temperature is 20 degree Celsius.When the balloon is at an ...

*November 1, 2011 by jennaq*

**PHYSICS**

Suppose you have a spherical balloon filled with air at room temperature and 1.0 atm pressure; its radius is 17 cm . You take the balloon in an airplane, where the pressure is 0.89 atm. If the temperature is unchanged, what's the balloon's new radius?

*March 31, 2016 by lizbeth*

**Physics**

An empty rubber balloon has a mass of 0.012kg. the balloon is filled with helium at 0 degrees celcius, 1 atm pressure, and a density of 0.179 kg/m3. the filled balloon has a radius of 0.5 m. a)what is the magnitude of the buoyant force acting on the balloon? b)what is the ...

*March 4, 2010 by Taylor*

**Physics**

An empty rubber balloon has a mass of 0.0120 kg. The balloon is filled with helium at 0 degrees celsuis, 1 atm pressure, and a density of 0.179kg/m^3. The filled balloon has a radius of .5m a)What is the magnitude of the net force acting on the balloon? b) What is the ...

*May 18, 2016 by Sara Draz*

**Physics**

A 1.8-g balloon is filled with helium gas. When a mass of 4.8 g is attached to the balloon, the combined mass hangs in static equilibrium in midair. Assuming that the balloon is spherical, what is its diameter? (The density of helium is 0.179 kg/m3, and the density of air is 1...

*November 7, 2011 by mymi*

**Physics**

A balloon with a mass of 90 kg is filled with helium (density = 0.179 kg/m3). The balloon is spherical and has a diameter of 11.0 m. What is the maximum mass that can be attached to the bottom of this this helium balloon, for it to be able to fly? The density of air is 1.29 kg...

*January 17, 2013 by Alphonse*

**Calculus**

A spherical balloon with radius 3 inches is partially filled with water. If the water in the balloon is 4 inches deep at the deepest point, how much water is released when the balloon hits the wall and breaks?

*February 18, 2015 by Andy*

**physics**

A large balloon of mass 237 kg is filled with helium gas until its volume is 318 m3. Assume the density of air is 1.29 kg/m3 and the density of helium is 0.179 kg/m3. (b) Calculate the buoyant force acting on the balloon.________N (c) Find the net force on the balloon and ...

*November 7, 2012 by Amanda*

**Math**

A spherical balloon expands uniformly as it is inflated. The radius of the balloon in r meters at time t seconds. Find the radius, the volume, and the surface area of the balloon when the rates of increase of the surface area of the balloon and the radius are numerically equal

*November 30, 2015 by Daniel *

**chem**

In 1897 the Swedish explorer Andree tried to reach the North Pole in a balloon. The balloon was filled with hydrogen gas. The hydrogen gas was prepared from iron splints and diluted sulfuric acid. The reaction is given below. Fe(s) + H2SO4(aq) FeSO4(aq) + H2(g) The volume of ...

*November 16, 2007 by mel*

**PHYSICS**

A large balloon of mass 237 kg is filled with helium gas until its volume is 318 m3. Assume the density of air is 1.29 kg/m3 and the density of helium is 0.179 kg/m3. (b) Calculate the buoyant force acting on the balloon. ________N (c) Find the net force on the balloon and ...

*November 8, 2012 by Amy*

**PHYSICS PLEASE HELP**

A large balloon of mass 237 kg is filled with helium gas until its volume is 318 m3. Assume the density of air is 1.29 kg/m3 and the density of helium is 0.179 kg/m3. (b) Calculate the buoyant force acting on the balloon. ____________N (c) Find the net force on the balloon and...

*November 8, 2012 by AMY*

**Chemistry**

The total mass that can be lifted by a balloon is given by the difference between the mass of air displaced by the balloon and the mass of the gas inside the balloon. Consider a hot air balloon that approximates a sphere 5.00 m in diameter and contains air heated to 65 C. The ...

*December 14, 2012 by Savannah*

**Chemistry**

The total mass that can be lifted by a balloon is given by the difference between the mass of air displaced by the balloon and the mass of the gas inside the balloon. Consider a hot air balloon that approximates a sphere 5.00 m in diameter and contains air heated to 65 C. The ...

*December 16, 2012 by Savannah*

**Calculus**

t: 0 2 5 7 11 12 r'(t): 5.7 4.0 2.0 1.2 0.6 0.5 The volume of a spherical hot air balloon expands as the air inside the balloon is heated. The radius of the balloon in feet is modeled by a twice-differentiable function of r of time t, where t is measured in minutes. For 0<t...

*November 25, 2008 by Craig*

**calculus**

a spherical balloon filled with gas has a leak that permits the gas to escape at a rate of 1.5 cubic meters per minute. how fast is the surface area of the balloon shrinking when the radius is 4 meters?

*November 7, 2013 by james*

**AP calculus AB**

A spherical balloon is being filled with air in such a way that its radius is increasing at a rate of 2 centimeters per second. At what rate is the volume of the balloon changing at the instant when its surface has an area of 4 pi square centimeters.

*December 29, 2010 by jennifer*

**help on calculus**

A spherical balloon is being filled with air in such a way that its radius is increasing at a rate of 2 centimeters per second. At what rate is the volume of the balloon changing at the instant when its surface has an area of 4 pi or 12.56637061 square centimeters?

*December 30, 2010 by winston*

**related rates problem-calculus**

A spherical balloon is being filled with air in such a way that its radius is increasing at a rate of 2 centimeters per second. At what rate is the volume of the balloon changing at the instant when its surface has an area of 4 pi square centimeters?

*December 30, 2010 by james*

**Calculus**

A spherical balloon is being inflated and the radius of the balloon is increasing at a rate of 2cm/min. At what rates are the volume and surface area of the balloon increasing when the radius is 5cm?

*April 26, 2016 by ChrismB*

**science**

You are a maker of hot air balloons and wish to construct a balloon that will lift you and a friend to places unknown. Your standard balloon design is a perfectly spherical, nylon fabric balloon with a small hole on the bottom for the burner that heats the air. Nylon starts to...

*April 11, 2013 by Sahil*

**calculus**

air is being pumped into a spherical balloon at a rate of 8 cm^3/min. Find the rate at which the radius of the balloon is increasing when the balloon's radius is 5 cm.

*April 8, 2013 by marisol*

**Physics :(( help please TT**

You are a maker of hot air balloons and wish to construct a balloon that will lift you and a friend to places unknown. Your standard balloon design is a perfectly spherical, nylon fabric balloon with a small hole on the bottom for the burner that heats the air. Nylon starts to...

*April 12, 2013 by Ian*

**physics**

A WEATHER BALLOON IS TO OPERATE WHERE THE DENSITY OF AIR IS 0.9Kg/m3. THE BALLOON HAS A VOLUME OF 20cm3 AND IS FILLED WITH NITROGEN WITH DENSITY 0.09Kg/m3. IF THE BALLOON BAG WEIGHS 118N, WHAT LOAD CAN IT SUPPORT AT THIS ALTITUDE?

*September 18, 2016 by cho*

**PHYSICS ASAP REPLY**

What is the difference between a hydrogen filled balloon and an air filled balloon moving in air? please answer. THe question is from the chapter PRESSURE.

*August 20, 2016 by A GOODSTUDENT*

**chemistry**

A weather balloon is filled with 0.295 m3 of helium on the ground at 18 °C and 756 torr. What will the volume of the balloon be at an altitude of 10 km where the temperature is 48 °C and the pressure is 0.14 atm?

*November 5, 2014 by jun*

**Physics**

A particle with a charge of -60.0 nC is placed at the center of a nonconducting spherical shell of inner radius 20.0 cm and outer radius 33.0 cm. The spherical shell carries charge with a uniform density of -2.02 µC/m3. A proton moves in a circular orbit just outside the ...

*April 14, 2011 by Danielle*

**math**

a spherical balloon with radius r inches has volume V9r) =(4/3)πr^3. Find a function that represents the amount of air required to inflate the balloon from a radius of r inches to a radius of r+1 inches

*September 12, 2010 by Sasha*

**SCIENCE **

What are the differences between a hydrogen filled balloon and an air filled balloon flying or moving in air?

*August 20, 2016 by THE MASTER*

**PHYSICS pressure**

What is the difference between a hydrogen filled balloon and an air filled balloon moving in air?

*August 20, 2016 by A GOODSTUDENT*

**Physics**

A hot air balloon of radius 12 meters has been heated so that the air inside has a density of 1.05 kg/m^3. What can the total load of the balloon be (mass of balloon itself plus cargo) if you need the balloon to accelerate into the air with an acceleration of 4 m/s^2?

*January 2, 2015 by Christina*

**Calculus**

A spherical balloon with a radius "r" inches has volume V(r)=(4/3)(pi)(r^3). Find the function that represents the amount of air required to inflate the balloon from a radius of "r" inches to a radius of r+1 inches.

*September 22, 2007 by Raj*

**math**

A spherical balloon with radius r inches has volume V (r) = 4 3 r3 . Find the function f(r) that represents the amount of air required to inflate the balloon from a radius of r inches to a radius of r + 2 inches.

*May 5, 2011 by Renaldo Nguyen*

**Calculus**

A spherical balloon with a radius r inches has volume V(r)= 4/3 Pi r^3. Find a function that represents the amount of air required to inflate the balloon from a radius of r inches to a radius of r+1 inches. An explanation would be appreciated, as I have no clue how to even begin.

*September 11, 2010 by Chelsea*

**math**

a boy is blowing a spherical balloon at a rate of 50 cm3/s.at what rate is the radius of the balloon changing when the radius is 10 cm?give your answer to 2 decimal places.

*October 11, 2011 by jj*

**math**

a boy is blowing a spherical balloon at a rate of 50 cm3/s.at what rate is the radius of the balloon changing when the radius is 10 cm?give your answer to 2 decimal places.

*October 11, 2011 by jj*

**Calculus**

a spherical balloon is inflated with gas at the rate of 500 cubic centimeters per minute. how fast is the radius of the balloon increasing at the instant the radius is 30 centimeters?

*November 1, 2009 by Anonymous*

**Calculus**

A spherical balloon is being inflated.Let r(t)=3t can represents its radius at time t seconds and let g(r)=4/3 pie r be the volume of the same balloon if its radius is r.Write (g.r) in terms of t and describe what it represents.

*July 16, 2016 by Anonymous*

**calculus**

A spherical balloon is leaking air at 2 cubic inches per hour. How fast is the balloon's radius changing when the radius is 2 inches.

*January 9, 2012 by Jordan*

**math**

Air is pumped into a spherical balloon at the rate of 20cm^3/s^-1.find the rate of change of radius of the balloon when the radius is 6cm

*November 25, 2015 by charles*

**Chemistry**

.Question part Points Submissions 1 0/0.5 2/3 Total 0/0.5 ...In the explosion of a hydrogen-filled balloon, 0.75 g of hydrogen reacted with 6.9 g of oxygen to form how many grams of water vapor? (Water vapor is the only product.) i already posted this but i dont think people ...

*September 11, 2010 by Rebekah*

**Physics**

A spherical helium filled balloon is attached to a string that is fixed to the ground. the balloon has a volume of .30/4m^3 and helium has a density of .20 kg/m^3. What is the weight of the balloon and helium if the tension on the string is .8N?

*October 11, 2013 by George*

**physics**

a spherical balloon of diameter 2m is filled with helium.Assume STP .how much is contained in the balloon helium

*May 1, 2015 by Anonymous*

**PHYSICS! HELIUM BALLON**

Under standard conditions, the density of air is 1.293 kg/m3 and that of helium is 0.178 kg/m3. A spherical helium balloon lifts a basket plus cargo of mass 277.0 kg. What must be the minimum diameter of the spherical balloon?

*April 25, 2016 by Mark*

**Physics**

A spherical helium filled balloon is attached to a string that is fixed to the ground. the balloon has a volume of .30/4m^3 and helium has a density of .20 kg/m^3. What is the weight of the balloon and helium if the tension on the string is .8N? What is the Gravitational force...

*October 11, 2013 by George*

**Physics**

A spherical helium filled balloon is attached to a string that is fixed to the ground. the balloon has a volume of .30/4m^3 and helium has a density of .20 kg/m^3. What is the weight of the balloon and helium if the tension on the string is .8N? What is the Gravitational force...

*October 11, 2013 by George*

**calc**

im so confused :( Willie Makit blows up a spherical balloon. He recalls that the volume is V=4/3Pi*r^3. In order for the radius to increase at 2cm/sec, how fast must Willie blow air into the balloon when the radius is 3 cm?

*December 29, 2010 by me*

**Physics**

A balloon of negligible mass is filled with helium gas (p=0.179 kg/m^3) until its volume is just large enough to lift a 25.0 kg load. (a) Find this volume. (b) Find the buoyant force exerted by air (p=1.29 kg/m^3) on the balloon.

*April 24, 2013 by Lashawn*

**math**

Air is pumped into a balloon such that its volume increases at the rate of 75cm^3 per second. It is assumed that the balloon is spherical all the time. Find in term of pi the rate at which the radius of teh balloon is increasing when the radius is 5cm. Given the balloon was ...

*March 27, 2014 by rosa*

**math- Calc**

a spherical balloon is filled with water. if the water is leaking out at a rate of 2 cm^3/min, find the rate at which the radius is changing when the volume is v=1000cm^3?

*April 22, 2014 by Louis*

**calculus**

A spherical balloon is being inflated at a rate of 10 cubic inches per second. How fast is the radius of the balloon increasing when the surface area of the balloon is square inches? Enter your answer correct to 3 decimal places.

*March 25, 2011 by Anonymous*

**physics I**

A lost shipping container is found resting on the ocean floor and completely submerged. The container is 5.4 m long, 2.3 m wide, and 2.4 m high. Salvage experts attach a spherical balloon to the top of the container and inflate it with air pumped down from the surface. When ...

*December 8, 2014 by Astro*

**Calculus**

A spherical balloon is being inflated at a rate of 10 cubic inches per second. How fast is the radius of the balloon increasing when the surface area of the balloon is 2pi square inches? Enter your answer correct to 3 decimal places.

*March 28, 2011 by Anonymous*

**Physics**

What minimum sized balloon would you have to fill in order to be able to be lifted into the air? Take your mass to be 100 kilograms and the temperature of the outside air to be 20 degrees C. Neglect the mass of the balloon rubber and basket and assume that the balloon is ...

*March 15, 2013 by steve*

**College Math**

A spherical balloon has a radius of 9 centimeters. Find the amount of air required to fill the balloon. Round to the nearest hundredth

*March 26, 2012 by Rochelle Finister*

**Chemistry**

need to know how to solve the following.... a gas filled weather balloon floating in the atomsphere has an initial volume of 850 L. The balloon rises to a region where the pressure is 56 kPa and its volume expands to 1700 L. If the temperature remains the same, what was the ...

*September 6, 2011 by remraf*

**physic**

an empty rubber balloon has 0.0120 kg it filled of helium. the density of helium is 0.179 kg/m^3 of and the radius of the balloon is 0.500 what is the buoyant force over the balloon

*December 5, 2015 by Sue*

**Calculus**

A spherical water balloon is being filled with water at the rate of 125 cubic inches per minute. At what rate is the radius increasing when the radius is 10 inches? At what rate is the surface area increasing?

*April 25, 2016 by Anonymous*

**Calculus**

Air is being pumped into a spherical balloon and the volume is increasing at the rate of 100 cubic cm per minute. How fast is the radius of the balloon increasing when the radius is 10 cm? (V=4/3 times pie times r^3)

*October 15, 2012 by Anonymous*

**calc**

hydrogen is being pumped into a spherical balloon at the rate of 250 cubic inches per minute. in a and b, you must provide an equation with their proper numerical factors when showing the relationships inquired A) write an equation showing the relationship between the rates at...

*November 15, 2007 by beckii*

**math**

A design on a balloon is 6 cm wide when the balloon holds 44 cm to the third power of air. How much must the balloon hold for the design to be 24 cm wide? Since the "width" increases by a factor of 4, the volume will increase by a factor of 4^3 = 64, even if the balloon is not...

*November 25, 2006 by Susie*

**Chemistry**

A hot air balloon is filled with hot air and the hot air forces the volume of the balloon to expand until the density of the gas in the balloon is less than the density of the outside air. The volume must be 20% larger than the balloon would be at STP in order for the balloon ...

*April 25, 2016 by Chem*

**chemistry**

A hot air balloon is filled with hot air and the hot air forces the volume of the balloon to expand until the density of the gas in the balloon is less than the density of the outside air. The volume must be 20% larger than the balloon would be at STP in order for the balloon ...

*April 25, 2016 by jenna*

**calc**

Air is being pumped into a spherical balloon so that its volume increases at a rate of 100 {cm}^3}. How fast is the surface area of the balloon increasing when its radius is 16{cm}?

*October 29, 2014 by john smit*

**physics**

A lost shipping container is found resting on the ocean floor and completely submerged. The container is 5.7 m long, 2.7 m wide, and 2.3 m high. Salvage experts attach a spherical balloon to the top of the container and inflate it with air pumped down from the surface. When ...

*March 10, 2013 by chel*

**Physics**

A lost shipping container is found resting on the ocean floor and completely submerged. The container is 6.0 m long, 2.2 m wide, and 2.3 m high. Salvage experts attach a spherical balloon to the top of the container and inflate it with air pumped down from the surface. When ...

*April 19, 2014 by Linda*

**Physics**

In this problem, your task is to analyze a lead balloon. The balloon in question is a hollow sphere of diameter of 20.0 m, constructed from a lead foil 0.25 mm thick and filled with helium gas. Below the balloon, a passenger basket is suspended. The mass of the passenger ...

*June 15, 2012 by Rob*

**calculus**

Air is being pumped into a spherical balloon so that its volume increases at a rate of 80cm^3/s. How fast is the surface area of the balloon increasing when its radius is 7cm?

*October 29, 2009 by Ash*

**Calculus**

A spherical balloon is inflated at a rate of 10 cubic feet per minute. How fast is the radius of the balloon changing at the instant the radius is 4 feet? And The radius of a circle is decreasing at a rate of 2 ft/minute. Find the rate at which the area is decreasing with ...

*August 26, 2011 by Branden*

**Chemistry**

You have two gas-filled balloons, one containing He and the other containing H2. The H2 balloon is twice the size of the He balloon. The pressure of gas in the H2 balloon is 1 atm, and that in the He balloon is 2 atm. The H2 balloon is outside in the snow (−5 °C), and ...

*March 30, 2007 by Luis*

**Math**

A spherical balloon with a surface area of 36pi square inches is inflated further until its diameter has increased by 50%. The surface area of the balloon is now? I know the formula for surface area is A=4pi*r squared. I don't understand how you can figure the problem without ...

*May 11, 2014 by Gayle*

**Math**

A spherical balloon expands when it is taken from the cold outdoors into a warm house. If the surface area increases by 50% (factor of 1.50), by what percentage does the radius of the balloon change? a)7.7% b)50% c)100% d)75% e)22%

*September 8, 2010 by Johnny*

**chem**

In the explosion of a hydrogen-filled balloon, 0.54 g of hydrogen reacted with 6.6 g of oxygen to form how many grams of water vapor?

*October 4, 2010 by jeff*

**Physics **

A 0.11-kg balloon is filled with helium (density = 0.179 kg/m3). If the balloon is a sphere with a radius of 5.4 m, what is the maximum weight it can lift?

*March 28, 2016 by Scott*

**Physics PLEASE help!**

I REALLY NEED HELP WITH THIS!!!!! In this problem, your task is to analyze a lead balloon. The balloon in question is a hollow sphere of diameter of 20.0 m, constructed from a lead foil 0.25 mm thick and filled with helium gas. Below the balloon, a passenger basket is ...

*June 16, 2012 by Eric*

**Calculus**

Air is being pumped into a spherical balloon so that its volume increases at a rate of 30 cubic centimeters per second. How fast is the surface area of the balloon increasing when its radius is 19 cm? V= 4/3*pi*r^3 S= 4 pi r^2

*September 24, 2009 by Z32*

**calculus**

Air is being pumped into a spherical balloon so that its volume increases at a rate of 80 cubic centimeters per second. How fast is the surface area of the balloon increasing when its radius is 8 cm?

*February 25, 2010 by idk*

**Calc**

Air is being pumped into a spherical balloon so that its volume increases at a rate of 90{cm}^3/s. How fast is the surface area of the balloon increasing when its radius is 7{cm}? Recall that a ball of radius r has volume \displaystyle V={4}/{3}pie r^3 and surface area S=4\pi r^2

*March 15, 2009 by Vince*

**physics**

Suppose that a party balloon is spherical, has a radius of 16 centimetres and is filled with helium. Furthermore suppose that we do our experiment under standard atmospheric conditions, when the air density is \(\rho = 1.225 kg/m^3\). How many of these balloons should a 75 ...

*March 26, 2014 by Nick*

**Chemistry **

You have two gas-filled balloons, one containing He and the other H2. The H2 balloon is twice the size of the He balloon (let the He balloon have a volume of 1 -L and the H2 balloon. a volume of 2 L). The pressure of gas in the H2 balloon is 1 atm while that in the He balloon ...

*February 19, 2012 by Bria*

**physics**

How big would a spherical helium balloon have to be to lift a 70kg person? The mass of the balloon's skin is 4.0kg

*November 19, 2013 by sandra*

**Math**

The radius, r cm , of a spherical balloon at a time t seconds is given by r = 3 + 2 / (1+t) What is the initial radius? Find the rate of change of r (w.r.t.t) when t=3

*January 28, 2015 by Aaqib zaman*

**Science**

1. Which type of weather technology often carries cameras that can make images of Earth's surface, clouds, and snow cover? A. weather balloon B. weather satellite**** C. computer D. automated weather station 2. Why are weather forecasts more reliable now compared to hundreds ...

*March 19, 2015 by Bob*

**physics**

What is the density of air filled balloon and the mass of 6 inch balloon air filled

*March 25, 2011 by ami*