Posts by Tom
Total # Posts: 1,407
An experimenter finds that no photo-electrons are emitted from tungsten unless the wavelength of light is less than 270nm. Her experiment will require photo-electrons of maximum kinetic energy 2.0eV. what frequency of light should be used to illuminate the tungsten?
September 23, 2014
White dwarf stars have been observed with a surface temperature as hot as 200,000 o C. What is the wavelength of the maximum intensity produced by this star? help please don't know what to do
September 23, 2014
Wow, you make me stay here for nearly an hour to wait for you to answer a question. Thanks. By the way, don't say how you didn't know the answer, you could have informed me of that 50min earlier.
September 18, 2014
The first one iswhat angle does a 3.8m ladder make with the ground, if it reaches 2.1m up the wall? The second one is A concreter uses a ramp to wheelbarrow in sand from the ground level to floor level inside a building under construction. Floor level is 75cm above ground ...
September 11, 2014
Each of the following is a typical feature of a fee-based internet back up service EXCEPT ______. backup to external hard drive universal access file feedback information delayed deletion
September 10, 2014
1) the prefix milli- means 1/1,000. how many times would you have to fill and empty a 10 ml graduated cylinder in order to fill a 1 liter soda bottle? i put 100 times. 2) what are eight examples of liquid products sold by volume
September 9, 2014
Hello, I am currently busy writing an essay and run against a wall: If government decreases the corporate tax rate, what would be the short-run and long-run effect on the aggregate supply, aggregate demand and Long-run aggregate supply in terms of shifts. (AS-AD Model) Would ...
September 9, 2014
never leave the fire on the stop unattended wash your hands after dealing with bacteria or anything dirty if there is broken glass don't pick it up with your bare hands always wear cooking mittens while dealing with hot objects
September 8, 2014
Find the mean Sample Value 1- 41.93 2- 12.55 3- 48.07 4- 90.81 5- 18.45 6- 55.81 I came up with 44.60 the online program "said close but check to see if yo made a round error" and at least three decimal places
September 7, 2014
The piperazine content of an impure commercial material can be determined by precipitating and weighing the diacetate: (C2H4)2N2H2 + 2 CH3COOH → (C2H4)2N2H2(CH3COOH)2 In one experiment, 0.3126 gram of the sample was dissolved in 25 mL of acetone, and 1 mL of acetic acid...
August 23, 2014
Suppose that inflation is 3% per year. This means that the cost of an item increases by 3% each year. Suppose a jacket cost $150 in 2011. How long will it take for the jacket to cost $300 dollars?
June 4, 2014
A pendulum consists of a swinging mass hanging from a massless string. The hanging mass is 2.0 kg and the string is 400.0 cm long. If the mass has a speed of 8.0 m/s when it passes the lowest point of its swing, a) what is the speed when the string makes an angle of 60.0o with...
May 30, 2014
A student places a zinc electrode in a 0.80 M Zn2+(aq) solution which is connected by an electrolyte to a 1.30 M Ag+ (aq) solution containing a silver electrode. (Note that the solution concentrations are not standard). Determine the initial voltage of the cell at 298 K. Show ...
May 13, 2014
A box of mass 1.50 kg is given an initial velocity of 12.5 m/s up an inclined ramp that makes an angle of 25.0o with the ground, which is horizontal. The coefficient of kinetic friction between the box and the ramp is 0.240. How long does the box slide up the ramp before it ...
May 13, 2014
A block is sitting on a rough ramp. It is found that a force of F = 200.0 N (directed up the ramp) is required to keep the box from sliding back down the ramp. The angle 𝜃 is 35.0o and the mass of the box is 150.0 kg. What is the coefficient of static friction between...
May 13, 2014
The temperature of an object in a experiment is T(t) = 60(1/3)^t + 10, where T is the temperature in degrees C and t is time in seconds. What is the domain and range of this situation?
May 4, 2014
Choosing verbs that agree in Number with Their Subjects: 1. Almost everybody (has,have) played games that originated in faraway places. MY ANSWER: HAVE 2. Few of these games (is,are) difficult to play. MY ANSWER: ARE 3. Pictures on ancient Greek pottery (show,shows) people ...
April 24, 2014
Proofreading a Parapgraph for Subject-Verb Agreement, Help with the errors: 1.Oridnary houses or a public building sometimes present problems for people with disabilities. 2. For example, a person using a wheelchair or crutches often have difficulty maneuvering in narrow halls...
April 24, 2014
Does the function satisfy the hypotheses of the Mean Value Theorem on the given interval? f(x)= ln(x) , [1,6] If it satisfies the hypotheses, find all numbers c that satisfy the conclusion of the Mean Value Theorem. (Enter your answers as a comma-separated list. If it does not...
April 16, 2014
A rectangular fence is to be built along a river using the river as one side of the fence.the cost of the fencing for the two ends is $8 per sq ft and the cost of the fencing for the side running parallel to the river is $12 per sq ft. If you have $3600 to spend on purchasing ...
April 15, 2014
Water flows through a pipe with the inner diameter of 20cm at a speed of 1m/s. How long does it take for the water flowing out from the pipe to fill a cylindrical tank with the base radius of 0.8m and the height of 0.5m?
April 14, 2014
Alex's favorite restaurant is a buffet-style Chinese restaurant downtown. Each time he goes, he chooses 2 appetizers and 1 entree. If the restaurant has four appetizers and 5 entrees to choose from, how many, times could Alex go to the restaurant without choosing the same ...
April 6, 2014
Scientists are experimenting with a kind of gun that may eventually be used to fire payloads directly into orbit. In one test, this gun accelerates a 8.9-kg projectile from rest to a speed of 4.2 × 103 m/s. The net force accelerating the projectile is 1.4 × 105 N. ...
March 16, 2014
If each voter voted for only one candidate what is the fewest number of voters who would have to vote differently in order for Susan to have received more votes than James if Susan had 212 votes and James had 244 votes?
March 11, 2014
a horizontal force of magnitude 20.0 N is applied to a 3.05 kg book as the book slides a distance d = 0.87 m up a frictionless ramp at angle θ = 30°. The book begins with zero kinetic energy. What is its speed at the end of the displacement?
March 2, 2014
A person in a kayak starts paddling, and it accelerates from 0 to 0.59 m/s in a distance of 0.43 m. If the combined mass of the person and the kayak is 72 kg, what is the magnitude of the net force acting on the kayak?
February 19, 2014
How would various company objectives affect the development of a marketing mix for a new type of internet browser software? If this company were just being formed by a former programmer with limited financial resources, list the objectives the programmer might have. Then ...
February 17, 2014
On a curved roadway of radius 100 m, the suggested speed limit is 35 mph (approximately 16 m/s). What must the coefficient of friction be between a cars tires and the road for the car to safely negotiate the curve at the posted speed?
January 30, 2014
1)Not sure 2) Increase in proton number, strong ENC forces. Increase dentsity and bonding. hence increased boiling point 3) Fe electronic configuration is [Ar] 3d6 4s2 Fe3+ is 3d5. All shells are full for Fe, Fe3+ isnt
January 22, 2014
A bag contains 5 blue, 4 red, 9 white, and 6 white marbles. If a marble is drawn at random and replaced 100 times, how many times would you expect to draw a green marble? Answer: 12/50
January 14, 2014