An anchor weighing 110 lb in water is attached to a chain weighing 2 lb/ft in water. Find the work done to haul the anchor and chain to the surface of the water from a depth of 35 ft.
March 21, 2014
Find Us=1/2k(deltax)^2 =1/2(180)(.15)^2 =2.025 This is spring potential energy. This must have been conserved from kinetic energy. Therefore Us=K=1/2mv^2 2.025=1/2(.195+.005)(v^2) v=4.5 m/s This is explains the time that the bullet is imbedded in the wood. To find the speed of...
March 11, 2014
How does Le Chatelier's principle explain the result you obtained when you add HCL to a suspension of Ca(OH)2 in water? Where the result was, precipitate dissappeared and an increase in temperature resulted.
February 24, 2014
Europeans were drawn in to sub-Saharan Africa in their quest for? a. gold and diamonds. b. diamonds and slaves. c. gold and slaves. d. slaves only. I can't find the correct answer. Please help! I believed it was gold and slave but it is not an option.... or is it c?? what ...
December 14, 2013
All are countries that were prominently Catholic in the 1500's and remain so today except? Spain France Italy Netherlands --- From my research, I see that Spain and Italy's main religion is Catholic. So I assume those two are not it. But I am confused on France and ...
December 13, 2013
Juana and Diego Gonzales, ages six and four respectively, own a strong and stubborn puppy named Corporal. It is so hard to take Corporal for a walk that they devise a scheme to use two leashes. If Juana pulls with a force of 23 lbs at an angle of 18Â° and Diego ...
December 12, 2013
It is very general question. I am supposed to write 2,000 words analytical essay but my teacher told me based on my topic I need to write it in journal entry with only intro being 200 words. When I hear "journal entry", it is not the same as an essay. Do you think ...
December 9, 2013
I have hard time understanding this wordings :( Turner thesis* by about a hundred years: the myth of the American west did more than anything else to shape the American character. Civilization by its very nature takes away our freedom, but as Americans we can always find ...
December 3, 2013
A______ is a tentative, testable explanation for an observed phenomenon. I am confused with hypothesis and theory. But my guess is hypothesis. is this true? or am I wrong?? thanks
November 28, 2013
There were 7 times as many marbles in Box A as in Box B. After Joyce transferred 294 marbles from Box A to Box B, both boxes had the same number of marbles. How man marbles were there in Box A at first.
November 20, 2013
So im told to find the value of each variable. It's a X. One side equals 3xº and the other side says (80-x)º 3x=80-x 4x=80 x=20 As you can see the value I got was 20. But in another question it tells me to find the measure of the labeled angles. How do I do that?
September 29, 2013
A solution is made by mixing 90.6 g of magnesium sulfate heptahydrate with 2320.0 g of water. 690.00 mL of the solution has a mass of 745.20 g. 1. What is the molarity of the magnesium sulfate solution? 2. What is the molarity of the magnesium ion? 3. What is the molality of ...
September 11, 2013
Oh. That makes more sense. Thank you. I have four more problems so I will work one more out so you could check it. -11=v/2-6 Add 6 to each side -11+6=v/2-6+6 -5=v/2 -5x2=v v=-10 Is this correct Mrs. Sue?
August 12, 2013
Okay. 3=r/16+4 My teacher told me to cross multiply so: 16x4=64 Then I get lost because I don't know the next step except to subtract three from both sides which gives you r/16=43.
August 12, 2013
Charge A has a charge of +2C. Charge B has a charge of -3C and is located 1 meter to the right of A. Charge C is located 1 meter to the right of Charge B and has a charge of -1C. If a fourth charge (Charge D) is placed 4 meters to the right of Charge B, how much charge must it...
August 8, 2013
A fence 5 feet tall runs parallel to a tall building at a distance of 2 feet from the building. We want to find the the length of the shortest ladder that will reach from the ground over the fence to the wall of the building. Here are some hints for finding a solution: Use the...
July 17, 2013
The equation 10(x-1)(x-2)(x-3) = 1 has three real solutions a<b<c where a = , b = , and c = . Enter your answers with at least six correct digits beyond the decimal point. Hint: Ask what the solutions are if the right hand side is 0 instead of 1, and use Newton's ...
July 17, 2013
Three objects of same heat capacity with temperature T1=200 K, T2=400 K and T3=400 K exchange heat with each other. They are isolated from the rest of the universe. Find the highest possible temperature one of them can reach in kelvin.
June 4, 2013
pyhsic question for count iblis
iblis got the problem right. for those trying to use jiskha to cheat on the brilliant problems, there was a mistake made in the acceptable answers for this week's question.
May 22, 2013
A car with a mass of 1000kg is travelling at a constant velocity. The force from the engine is 200Newtons. Calculate the acceleration of the car using the formula f=ma. How long will it take this car to travel 0-60 mph (n.b. 1mph = 0.45m/s)
May 16, 2013
A massless spring, with K=425 N/m, is hung vertically with the bottom end of the spring at position Y.i. A 3.50 kg mass is attached to the bottom of the spring and allowed to fall and oscillate. A) How far below Y.i does the mass fall before coming momentarily to rest and ...
May 1, 2013
The planet Tralfamador is a planet of mass M and radius R, and very thin atmosphere (neglect air resistance). A magnetic rail gun has been mounted on the surface of Tralfamador at the North pole. A projectile of mass m is fired from the magnetic rail of gun with an unknown ...
May 1, 2013
Some communication satellites are put into a circular geosynchronous orbit in which the satellite remains above a certain position on the earth's equator as it orbits. Such a satellite would always be in the same position in the sky as seen from the transmitting or ...
May 1, 2013
C'mon @cheers!! get some rest :) 5A is not (0,-1), or (0,1/sqrt(K)) or (0,-1/sqrt(N)) xD It must be something very close to it... I think the answer is translating the grover algorithm to a Bloch Sphere and see how it moves around the surface :) At least, that is what 5B,c...
April 16, 2013
Hi PhysTech, I am reading an article from twistedoakstudios(at)com in /blog/Post2644_grovers-quantum-search-algorithm and doing some calculations... Seems cyclic, in a geometric view.
April 16, 2013
A plastic rod has been bent into a circle of radius R = 8.80 cm. It has a charge Q1 = +4.60 pC uniformly distributed along one-quarter of its circumference and a charge Q2 = -6Q1 uniformly distributed along the rest of the circumference. Take V = 0 at infinity. (a) What is the...
April 4, 2013
A circular loop of wire (radius = 6.0 cm, resistance = 40 miliamps) is placed in a uniform magnetic field that makes and angle of 30 degrees with the plane of the loop. The magnitude of the field changes with time according to B = 30 sin (20t)mT, where t is measured in s. ...
April 1, 2013
A coffee cup calorimeter contains 25.0 grams water at 23.8 C A 5.00g sample of an unknown metal at an initial temperature of 78.3 C was dropped into the calorimeter. The final temperature of mixture was 46.3 C. Calculate the specific heat of the metal. The specific heat of ...
March 19, 2013
Phosphorus pentachloride decomposes according to the chemical equation PCl5(g) <-> PCl3(g)+Cl2(g) Kc=1.80 at 250 degrees Celsius A 0.222 mol sample of PCl5(g) is injected into an empty 3.25 L reaction vessel held at 250 °C. Calculate the concentrations of PCl5(g) and...
March 3, 2013
(a) LEFT For left hand or right hand rule, every extra digit requires 10 times of work. 4 digit needs 2 second. From 4 to 12, it has 8 digits. 2 * 10^(8) seconds / 60 /60 /24 /365 = 6.3 years (b) MID For midpoint rule, every 2 digit requires 10 times of work. 2 * 10^(8/2) /60...
February 25, 2013
Place twelve $1 bill and twelve $10 bill on the template. Than exchange bills so that the same amount of money is on the template using the fewest number of bills. Write the result in expanded form
February 20, 2013
Place twelve $1 bill and $10 bill on the template. Than exchange bills so that the same amount of money is on the template using the fewest number of bills. Write the result in expanded form
February 20, 2013
A sample of naphthalene, which should be pure white, was found to have a grayish color after the usual purification procedure. The melting point was correct, and the melting point range was small. Explain the gray color.
January 30, 2013