Sunday

February 7, 2016
Total # Posts: 547

**Physics**

A blue whale materializes 11.5 km above an airless planet with an acceleration of gravity of 6.85 m/s2. What is the speed of the whale right before impact? (Work-Energy Theorem)
*March 21, 2012*

**Physics**

A car is driven at a constant speed of 85 km/h down a road. The car's engine delivers 49.2 kW of power. Calculate the average force that is resisting the motion of the car.
*March 21, 2012*

**Physics**

Michelle pulls a 14.5 kg wheeled cart with a rope along a flat road. The rope makes a 28.0 degree angle with the horizontal. If the tension in the rope is 350 N and she pulls the cart 56.7m how much work does Michelle do?
*March 21, 2012*

**Physics**

Bryant is fired from a cannon with an initial speed of 14 m/s. If his mass is 80 kg what is his initial kinetic energy?
*March 21, 2012*

**Physics**

A ball is moving at 82 m/s when it hits a ball at rest which has a mass fours times as big as its own. The formally stationary ball leaves the collision with a speed of 7.5 m/s what is the final velocity of the first ball?
*March 21, 2012*

**physics**

Neona is on a tricycle A, combined mass 62 kg, and Alyssia is on tricycle B, combined mass 54 kg. They are initially at rest, but they push off of each other. What is Neona's speed immediately after the push if Alyssia's is 4.2 m/s?
*March 21, 2012*

**Physics**

Kenya finally loses her cool and punches her teacher. The teacher weighs 85 kg. He sees the punch coming and begins to back up at a speed of 0.60 m/s. After Kenya clocks him, he is moving backwards at a speed of 0.82 m/s. If the contact time of Kenya's fist to the teachers...
*March 21, 2012*

**Physics**

Two trucks that appear to be identical collide on an icy road. One was originally at rest. The trucks stick together and move off at more than half the original speed of the moving truck. What can you conclude about the contents of the two trucks?
*March 21, 2012*

**Physics**

You are sitting at a baseball game when a foul ball comes in your direction. You prepare to catch it barehanded. In order to catch it safely, should you move your hands toward the ball, hold them still, or move them in the same direction as the moving ball? Explain.
*March 21, 2012*

**Physics**

As you lift a chair to store is upside down on a desk, gravity exerts a force, mg, downward and you exert a force of the same magnitude upwards. The two forces are equal in magnitude and opposite in direction. From this is would appear that no work was done, but you know you ...
*March 21, 2012*

**Physics**

Roads seldom go straight up a mountain, they wind back and forth. Explain why this is useful
*March 21, 2012*

**math**

6+10+6+7+6=35
*March 7, 2012*

**math**

i have 3 numbers 10,7,and 6 and need to make them work in 35...but it cant be like 7 into 35 it has to be all 3 numbers and can be used more than once but after another number like 10 + 7 +10 ect
*March 7, 2012*

**Math**

circumference (the crust)= 3.14(pie)*radius^2 C=3.14*12^2 (12 inch) = 452.16 C=3.14*8^2 (8 inch)=200.96 452.16 minus 200.96 = 251.2 in in diameter
*March 6, 2012*

**physics**

Determine the velocity of a satellite orbiting Earth at a height of 3.2 x 10^3 meters.
*March 1, 2012*

**physics**

Jessica, who mass is 55 kg, is 3.50 meters away from a 0.20 kg bag of Fig Newtons. What is the gravitational force between Jessica and the cookies?
*March 1, 2012*

**physics**

Imagine a planet that orbited the sun at a distance three times that of Earth. What would the period of that planet be in Earth years?
*March 1, 2012*

**physics**

A car is rounding a curve with a radius of 12.0 m at 8.2 m/s when it hits a slippery patch. What is the minimum coefficient of static friction between the car and the slick patch of road that will allow the car to round the corner safely?
*March 1, 2012*

**physics**

Someone swints a 3.0 kg mass at the end of a 2.3 m string in a horizontal circle. If the string can withstand a tension of 80 N, at what speed can they swing the mass before they risk a lawsuit?
*March 1, 2012*

**Thermodynamics**

Consider a system consisting of two glass bulbs, each with volume V, and each containing n moles of gas. Bulb A contains nA moles of A and bulb B contains nB moles of B (a different gas), nA = nB. The bulbs are connected by a closed stopcock. The stopcock is opened so that the...
*February 22, 2012*

**physics**

In a water balloon toss a contestant throws her balloon with a speed of 4.84 m/s at an angle of 16.5 degrees above the horizontal. Find the maximum height, the time of flight and the range of the balloon assuming her partner catches the balloon at the same height at which it ...
*February 6, 2012*

**physics **

A man is using a bow and arrow for the first time of his life. He is 25 meters from the target and aims directly at the center of the target. Surprisingly the arrow leaves the bow with a velocity of 54 m/s directly towards the center of the target and initially the velocity is...
*February 6, 2012*

**physics**

Many professional golfers can hit a golf ball 300 meters with a driver. The face of a driver and the swing pattern causes the ball to leave the club at around 18 degrees from the horizontal. Assuming the ball travels exactly 300 meters in the air before it bounces the first ...
*February 6, 2012*

**physics**

a mass being held by a string moves with speed v on a circular path of radius r, and has a period of revolution T. if it was desired to travel one revolution in twice as much time as before, what would be the radius of the path? what if the time was halved?
*January 22, 2012*

**AP Statistics **

Nurse practitioners are nurses with advanced qualifications who often act much like primary care physicians. Medical researchers wnat to design a study to compare the effectiveness of nurse practitioners and physicians. They recruit 1200 volunteer subjects for the tudy, each ...
*December 16, 2011*

**ALGEBRA**

Suppose you have a $1,000 charge on a credit card charging 1% monthly interest using the adjusted balance method. The minimum payment due in May is $70. How much will you save in interest charges in June by paying $140 instead?.
*November 26, 2011*

**microeconomics**

if the price elasticity of demand for a cup of tea is equal to 3, how would you interpret this result?
*November 17, 2011*

**Calculus**

You are the owner of a delivery company with one truck. The trucks fuel economy is 1200/x miles per gallon when driving at x miles per hour (where 80 >= x <= 110). The price of fuel is $1 per gallon. You pay the truck driver $8 per hour. If a delivery 100 miles away is ...
*November 17, 2011*

**Calculus**

OH NEVER MIND! I GOT IT HAHAHA!
*November 6, 2011*

**Calculus**

Oh i shoud've been more specific, what i meant to ask was how do you find xa, ya etc. at 1/2 hours? Thanks in advance! :)
*November 6, 2011*

**Calculus**

THANKS FOR ALL THE HELP! One question, how do you find xa,ya, xb, and yb?
*November 6, 2011*

**Calculus**

At 1:00 p.m. ship A is 25 km due north of ship B. If ship A is sailing west at a rate of 16km/h and ship B is sailing south at 20km/h, find the rate at which the distance between the two ships is changing at 1:30 p.m.
*November 6, 2011*

**chemistry**

.115 mol of solute is put in a container and water is added to give 250ml of solutrion. what is the molarity
*November 4, 2011*

**Calculus**

For question a), how did you get 12800? Where'd that come from?
*November 1, 2011*

**statistics**

What is the standard deviation of a normal distribution, whose mean is 35, in which an x-value of 23 has a z-score of -1.63?
*October 13, 2011*

**College Physics**

In this problem you will estimate the heat lost by a typical house, assuming that the temperature inside is T(in) = 20 degrees celcius and the temperature outside is T(out) = 0 degrees celcius. The walls have fiberglass insulation, which dominates the heat conduction ...
*October 8, 2011*

**College Physics**

The top layer of your goose down sleeping bag has a thickness of 5.0 cm and a surface area of 1.0 m^2. When the outside temperature is -18 degrees celcius you lose 24 Cal/hr by heat conduction through the bag (which remains at a cozy 34 degrees celcius inside). Assume that you...
*October 7, 2011*

**College Physics**

the answer is 0.027
*October 7, 2011*

**College Physics**

is k 0.023076923 ?
*October 7, 2011*

**College Physics**

The top layer of your goose down sleeping bag has a thickness of 5.0 cm and a surface area of 1.0 m^2. When the outside temperature is -18 degrees celcius you lose 24 Cal/hr by heat conduction through the bag (which remains at a cozy 34 degrees celcius inside). Assume that you...
*October 7, 2011*

**College Physics**

Nvm. I found the answer :) It's 555 W. (.200 W/m x K)(22m^2)[(19.3-16.4)/0.0230 m]
*October 7, 2011*

**College Physics**

A 2.30-cm-thick wood floor covers a 4.0 m x 5.5 m room. The subfloor on which the flooring sits is at a temperature of 16.4 degrees celcius, while the air in the room is at 19.3 degrees celcius. What is the rate of heat conduction through the floor? Use 0.200 W / m x K for the...
*October 7, 2011*

**Organic chemistry**

You are at isoelectric point for a solution of Leucine. If the number of negatively charged carboxyl ate groups, -COO-, is 1x10^19, how many positively charged amino groups, NH3+, would there be?
*October 5, 2011*

**college physics**

1 and 2 only :)
*October 4, 2011*

**Chemistry **

Why is the solubility of KHTar greater in a 0.10M NaNO3 solution than in distilled water?
*July 14, 2011*

**Spanish -9th grade-Please check and advise**

I figured it out. I could say "Normalmente tengo mucha tarea en la clase."
*May 16, 2011*

**Spanish -9th grade-Please check and advise**

I need to write about my geometry class and what I do in the class. I need to use "la tarea" in the sentence. I'm not sure if I could use this to describe the calculations I do. I'm confused how to even conjugate or use this. Would it start with "Hago la...
*May 16, 2011*

**math**

My mother and I are the same age – only the numbers are reversed (21,12 for example) Twelve years ago my mom was twice as old as me. So how old is my mommy and how old am I?
*May 9, 2011*

**technical math/precal**

18/3square roots of 6-7square roots of 2
*May 3, 2011*

**physical science**

The resultant vector of two particular displacement vectors dose not equal the sum of the magnitudes of the individual vectors. Describe the directions of the two vectors.
*May 2, 2011*

**science**

a person exerts 35 lbs of force to turn a door handle ( radius = 4 cm). How much force is exerted on the inner "axle" with a radius of 5 mm?
*May 1, 2011*

**Chemistry**

How do you calculate the heat fusion of ice? I have the initial and final temperatures and volume of the water.
*April 26, 2011*

**math**

4,200/120=
*April 26, 2011*

**Chemistry**

106 g of iron at 84.0°C are placed in contact with 205 g of silver at 11.0°C. If no heat is lost to the surroundings, what is the final temperature of the metals? The specific heat of iron is 0.418 J/g·°C and that of silver is 0.251 J/g·°C. 92.0 g...
*April 25, 2011*

**Statistics**

Discuss how a t Test can be employed in hypothesis testing by the use of directional vs. non directional hypotheses. Discuss types of research where using the t statistic may be an appropriate alternative to using a z-score.
*April 20, 2011*

**chemistry**

Fe2O3+ 3CO=2Fe+3Co2, suppose that 1.64kg of Fe are obtained from a 2.62kg sample of Fe2O3 (ore). assuming that the reaction goes to completion, what is the percent purity of the Fe2O3 in the original sample.
*April 19, 2011*

**CHEMISTRY**

Fe2O3 + 3CO= 2Fe + 3CO2, SUPPOSE THAT 1.64kg OF Fe ARE OBTAINED FROM A 2.62kg SAMPLE OF Fe2O3(ORE). ASSUMING THE REACTION IS COMPLETE, WHAT IS THE PERCENT PURITY OF THE Fe2O3 IN THE ORIGINAL SAMPLE?
*April 17, 2011*

**Physics**

A trapeze artist weighs 8.00 x 10^2 N. The artist momentarily held to one side of a swing by a partner so that both of the swing ropes are at an angle of 30º with the vertical. In such a condition of static equilibrium, what is the horizontal force being applied by the ...
*April 13, 2011*

**health**

Is there anyone that could possibly help me understand medical terminology? My college course has transitioned to an all online setting with in-class closed book exams. I'm having a hard time understanding the difference in word roots and combining forms. For instance: she...
*April 11, 2011*

**math**

Consider a party with 60 people. Assume each person knows more than m other people. How large must m be to guarantee that 3 people know each other?
*March 31, 2011*

**geometry**

The ratio of the areas of two similar trapezoids is 1:9. What is the ratio of the lengths of their altitudes?
*March 30, 2011*

**Physics**

I figured it out! PEg = gmh W = Fh PEg/W
*March 29, 2011*

**Physics**

A pulley system is used to lift a piano 2.6 m. If a force of 2510 is applied to the rope as the rope is pulled in 14 m, what is the efficiency of the machine? Assume the mass of the piano is 750 kg. I know the equation is eff = Wout / Win I'm just confused on what I'm ...
*March 29, 2011*

**Physics**

A 14,300 N car traveling at 46.0 km/h rounds a curve of radius 2.30 x 10^2 m. What is the minimum coefficient of static friction between the tires and the road that will allow the car to round the curve safely?
*March 29, 2011*

**Physics**

thank you sooo much!
*March 29, 2011*

**Physics**

Tarzan tries to cross a river by swinging from one bank to the other on a vine that is 10.2 m long. His speed at the bottom of the swing is 7.6 m/s. Tarzan does not know that the vine has a breaking strength of 1.0 103 N. What is the largest mass that Tarzan can have and still...
*March 29, 2011*

**Physics**

A satellite with an orbital period of exactly 24.0 h is always positioned over the same spot on Earth. This is known as a geosynchronous orbit. Television, communication, and weather satellites use geosynchronous orbits. At what distance would a satellite have to orbit Earth ...
*March 29, 2011*

**Physics**

A tennis player places a 58 kg ball machine on a frictionless surface, as shown below. The machine fires a 0.068 kg tennis ball horizontally with a velocity of 31.6 m/s toward the north. What is the final velocity of the machine? ______m/s to the south
*March 21, 2011*

**11 grade English**

In Swimming Strokes by Lee Carroll in paragraph 1, how many errors are there in subject-verb agreement, parallelism, and pronoun-antecedent agreement?
*March 21, 2011*

**Physics**

A 57.8 kg pole-vaulter falls from rest from a height of 5.4 m onto a foam-rubber pad. The pole-vaulter comes to rest 0.25 s after landing on the pad. (a) Calculate the athlete's velocity just before reaching the pad. ______ m/s downward (b) Calculate the constant force ...
*March 21, 2011*

**Physics**

An 95.0 kg astronaut is working on the engines of a spaceship that is drifting through space with a constant velocity. The astronaut turns away to look at Earth and several seconds later is 26.3 m behind the ship, at rest relative to the spaceship. The only way to return to ...
*March 21, 2011*

**physics**

µk x (m x g) x d x cos 30º 0.40 x (290 x 9.81) x 4.0 x cos 30º hopefully that works
*March 21, 2011*

**High School Chemistry**

10mL of 0.10M HCl is given. What is the pH? How many milliliters of 0.10M NaOH would be required to neutralize it? What is the pH of the neutralized solution? What would the pH of the solution be if you added 20mL of NaOH? Here's what I have so far: pH of HCl=-log(0.10M)= ...
*March 21, 2011*

**Newton' law of motion**

Force = mass x acceleration 50N=10kg x a
*March 9, 2011*

**Physics**

thank you.
*March 9, 2011*

**Physics**

A 50.0 kg diver steps off a diving board and drops straight down into the water. The net force when in the water is an upward 1450 N. If the diver comes to rest 5.0 m below the water's surface, what is the total distance between the diving board and the diver's ...
*March 9, 2011*

**physics**

A ^9 Be nucleus containing four protons and five neutrons has a mass of 1.50×10−26 kg and is traveling vertically upward at 1.70 km/s. If this particle suddenly enters a horizontal magnetic field of 1.25 T pointing from west to east, find the direction of its ...
*March 9, 2011*

**college prep math**

what is the least common denominator of (x-4/5x^2-14x-3)-(2x/10x^2-3x-1)+(7x-2/2x^2-7x+3)
*March 3, 2011*

**physics**

Four forces act on a hot-air balloon, F_1 is upward at 4600 N, F_2 is left at 1450 N, F_3 is right at 850 N, and F_4 is downward at 3600 N. ____ N at _____ degrees clockwise from F_2.
*February 22, 2011*

**physics**

A 2.32 kg book is dropped from a height of +3.7 m. a.) What is its acceleration? b.) What is its weight in newtons?
*February 22, 2011*

**physics**

a 2 kg rabbit starts from rest and is moving at 6 m/s after 3 seconds. What force must the rabbit cause to makes this change in speed?
*February 22, 2011*

**math**

If i paid 1.25 in sales tax for an item i purchased. the sales tax rate was 5%. What was the price of the item before tax
*February 15, 2011*

**physics**

How many joules of energy are required to run a 100 W light bulb for one day? Burning coal yields about 30x10 to the 8J of energy per kilogram of coal burned. Assuming that the coal power plant is 30% efficient, how much coal has to be burned to light the bulb for one day?
*February 2, 2011*

**geometry**

what is approximate area of triangle if each side is 36 inches long
*January 31, 2011*

**marketing**

ABC Technologies manufactures computer accessories, such as modems and network cards. Even though the company has several purchasing managers, the company president has final authority on all purchases over $500, including the selection of the supplier. In the typical buying ...
*January 30, 2011*

**Physics**

Thanks it worked :)
*January 2, 2011*

**Physics**

Im using the F=Gm1m2/r^2. So to figure out the y i plugged in the values for massA and B and used a radius of .5 to get 2.96E-7. For the x i used the same formula but did it twice once for particle CB and the other for BD. then i added them together and got -1.74E-7.
*January 2, 2011*

**Physics**

Four uniform spheres, with masses mA = 37 kg, mB = 30 kg, mC = 220 kg, and mD = 55 kg, have (x, y) coordinates of (0, 50 cm), (0, 0), (-77 cm, 0), and (44 cm, 0), respectively. Find the net force on sphere B due to the other spheres. What are the (a)x and (b)y components of ...
*January 2, 2011*

**Physics-Gravitation**

when i plugged in the values i got 4.62E10 is that number suppose to be negative or positive?
*January 2, 2011*

**physics**

A coin is placed on a vinyl stereo record that is making 78 revolutions per minute on a turntable. Find the magnitude of the acceleration when the coin is placed 5.0, 10, and 17 cm from the center of the record. The radius of Earth is about 6.38x10^3 km. A 7.40x10^3 N ...
*December 13, 2010*

**Math**

Give vertex, axis, x-intercepts and y-intercepts to parabola y= -3x^2-6x+4
*November 24, 2010*

**Chemistry**

I'm having a hard time with a question predicting the reaction (if any) of 1,2-dichloroethane and sodium iodide, sodium iodate, and sulfuric acid. Any suggestions? Thanks!
*November 16, 2010*

**Chemistry**

I'm having a hard time with a question predicting the reaction (if any) of 1,2-dichloroethane and sodium iodide, sodium iodate, and sulfuric acid. Any suggestions? Thanks!
*November 16, 2010*

**Physics**

Work = Force x distance Both traveled the same distance (flight of stairs) & both were composed of the same force (weight). Therefore, they both exerted the same amount of force. However, the first person who climbed the stairs at 30 s exerted more energy at less time than the...
*November 15, 2010*

**Mathematics **

Find the periodic payment that will amount to the given sum under the given conditions: S=$150,000; interest is 6% compounded semiannually; payments are made at the end of each semiannual period for 11 years
*November 7, 2010*

**chemistry**

Can someone please explain why there are so many gas laws. I've been doing my homework with the appropriate formulas, but I'm confused why everyone keeps say that PV=nRT is so wonderful? You can't get the same solution by using this ONE formula, so what is so ...
*November 7, 2010*

**Chemistry**

What is the molarity of 350 mL of solution that contains 27 g of CaCl2?
*November 5, 2010*

**Chemistry**

What is the mass of 1.665 x 10 to the 22nd formula units of calcium acetate,Ca(C2H3O2)2?
*November 5, 2010*

**Chemistry**

What is the molar mass of calcium acetate, Ca(C2H3O2)2?
*November 5, 2010*