Total # Posts: 760
John is driving at a constant speed of 20.0 m/s when he passes Jane, who is traveling in the same direction at 15.0 m/s at the moment that John passes her. If Jane is accelerating at 2.0 m/s2, how far will Jane drive before she catches up to John? How much time passes from ...
April 15, 2014
Draw each of the following vectors on graph paper, then find the x- and y- components. Make sure to include units in your answers for the components. a) ⃑r = (65 m, 30degrees above the positive x-axis) b) ⃑v = (125 m/s, 40degrees below the negative x-axis) c) ...
April 7, 2014
Two full 48-gallon tanks begin draining at t = 0. Tank Alpha's volume is changing at a constant rate of -16/5 gal/min. The rate at which Tank Bravo's volume is changing is given by r(t)=-1/3t-1 gal/min. a) How much water is in each tank after 5 minutes? b) Which tub ...
April 7, 2014
A cubic meter of some material has a mass of 6400 kg. The block of material is lowered into a lake by a strong cable until the block is completely submerged. Draw a free-body diagram for the block. (Do this on paper. Your instructor may ask you to turn in your work.) Find the ...
March 31, 2014
A DC circuit has a single battery of voltage V = 10.0 V attached to a resistor R = 100 Ohms. If the voltage is increased to 20.0 V, then by what factor does the power emitted by the resistor increase?
March 5, 2014
Please Help with 2 Physics Problems???
1) In a two-dimensional tug-of-war, Alex, Betty, and Charles pull horizontally on an automobile tire at the angles shown in the picture. The tire remains stationary in spite of the three pulls. Alex pulls with force FA of magnitude 207 N, and Charles pulls with force FC of ...
February 17, 2014
A plane flies 407 km east from city A to city B in 44.0 min and then 871 km south from city B to city C in 1.90 h. For the total trip, what are the (a) magnitude (in km) and (b) direction of the plane's displacement, the (c) magnitude (in km/h) and (d) direction of its ...
February 10, 2014
The treasurer of the student body at a college reported that the receipts from a recent contact totaled $916; Furthermore, he announced that 560 people had attended the concert. Students were charged $1.25 each for admission to the concert, and adults were charged $2.25 each. ...
February 1, 2014
which of the following do rain forests and taiga have an common? A. similar average annual rainfalls. B. similar average annual temperature C. heavily populated with trees. D. tend to occur in similar latitudes
January 30, 2014
Suppose the following data are selected randomly from a population of normally distributed values. 42 51 43 48 41 57 54 39 45 48 45 39 46 Construct a 95% confidence interval to estimate the population mean. Round the intermediate values to 2 decimal places. Round your answers ...
December 19, 2013
1) A dog has the same mass for 3 years. State whether this represents an equilibrium or steady state situations, and give your reasons. I'm not sure if I got this question right... I think this is a steady state because the dog is opened to the environment where oxygen is ...
November 25, 2013
a .150kg object tied to a string is whirled in a horizontal circle ata constant angular speed of 3.50 revolutions per second. the tension is the string is 75newtons. what is the length of the string?
October 27, 2013
A "swing" ride at a carnival consists of chairs that are swung in a circle by 19.8 m cables attached to a vertical rotating pole, as the drawing shows. Suppose the total mass of a chair and its occupant is 144 kg. (a) Determine the tension in the cable attached to ...
October 3, 2013
At an amusement park there is a ride in which cylindrically shaped chambers spin around a central axis. People sit in seats facing the axis, their backs against the outer wall. At one instant the outer wall moves at a speed of 3.44 m/s, and an 64.3-kg person feels a 277-N ...
October 3, 2013
A centrifuge is a device in which a small container of material is rotated at a high speed on a circular path. Such a device is used in medical laboratories, for instance, to cause the more dense red blood cells to settle through the less dense blood serum and collect at the ...
October 3, 2013
a student is given a 10 gram sample of gold that has a density of 19.32g/cm3. The student is then given a 5 gram sample of an unknown substance and told the density of the unknown substance is 19.32g/cm3. What is the unknown substance
September 10, 2013
in the reaction of magnesium metal with hydrochloric acid to produce magnesium chloride and hydrogen gas. If 4.59 mol of magnesium and 4.59 mol of hydrochloric acid are reacted, how many moles of magnesium chloride are produced ?
August 26, 2013
Find the equation of the tangent line to the curve (piriform) y^2=x^3(4−x) at the point (2,16−−ã). a. Find dy/dx at x=2. dy/dx= b. Write the equation of the tangent line to the curve.
June 25, 2013
The radius of a circular disk is given as 51 cm with a maximum error of 0.04 cm. Use differentials to estimate the maximum error and percent error in the calculated area of the disk.
June 19, 2013
Oscar Corporation is planning to construct an elliptical gate at its headquarters. The width of the ellipse will be 5 feet across and its maximum height along the center will be 3 feet. The company wants to place two bright spots at the foci of the ellipse. How far from the ...
May 1, 2013
kate cut a pizza into fourths. karl cut a pizza of the same size into sixth. After they each ate some pizza, they had the same fraction of pizzas left. What fraction of each pizza was left?
April 23, 2013
Thimerosal is an organic compound (gram molecular mass = 404.8 g/mol) used to inhibit bacterial growth. A .100%solution of thimerosal is sometimes used as an antiseptic. Assume that this solution has a density of 1.00 g/mL. A. how many grams of thimerosal are found in .500 g ...
April 7, 2013
A survey team is trying to estimate the height of a mountain above a level plain. From one point on the plain, they observe that the angle of elevation to the top of the mountain is 25 degrees. From a point 1225 feet closer to the mountain along the plain, they find that the ...
March 10, 2013
The sum of twice a number and another number is 24. The difference of twice the first number and the other number is 12. Which system would model this situation, and what is the solution?
February 22, 2013
A certain brand of cereal costs $3.25 per box before sales tax is added. When you buy 5 or more boxes of this cereal you receive 1 additional box for free. What is the average cost per box of cereal for 6 boxes before sales tax are added ? Please helpp
February 5, 2013
1. Pentane gas (C5H12) combusts with oxygen gas (O2) to form water (H2O) and carbon dioxide (CO2). Write a balanced chemical equation for this reaction and explain the scientific principle (statement) that requires the balancing of an equation to make it conform to reality
January 15, 2013
a mechanic uses a chain and bloc pulley to lift a 875-kg engine 4.0 m to the top of the garage. the downward force on the chain over the 4.0 m distance is 5.0 x 10^4 N. a)calculate the work done in raseing the motor b)how much useful work was done c)what is the inefficiency of...
January 12, 2013
Madison spent 5/8 of her savings on a microwave oven & a refrigerator. She used 4/7 of the amount she spent to buy the refrigerator. The refrigerator cost $280 more than the microwave oven. How much savings did Madison start with?
January 1, 2013
If you are asked to determine an objects speed, what information must you have? A.distance and period of time B.distance and change in position C.period of time and direction D.distance and direction
December 17, 2012
You have a conversation of EP and with that you have the formula: Mbull*Vi+Mwood*Vi=(Mb+Mw)Vf .o15kg*Vi+15*0=(.015+15)Vf Mult. by 0: .015kg*Vi=(.o15+15)Vf So we can't solve that (i guess we cant curse here) but we move on to where the spring compresses, there is ...
December 2, 2012
You have a conversation of EP and with that you have the formula: Mbull*Vi+Mwood*Vi=(Mb+Mw)Vf .o15kg*Vi+15*0=(.015+15)Vf Mult. by 0: .015kg*Vi=(.o15+15)Vf So we can't solve that but we move on to where the spring compresses, there is conservation of TME so: 1/2(Mb+Mw)Vf^2...
December 2, 2012