# Posts by MELISSA

Total # Posts: 1,327

physics
Any my text book for the 12.0kg steel ball it says the answer is 1.2*10^2N, not 117.6N how did they get that answer?

physics
Calculate Earth's force of gravity on each of two steel balls of masses 6.0kg and 12.0kg I the forces of gravity on the 12-kg ball is greater than that on the other ball, why do the two balls accelerate at the same rate when dropped?

trig
389 miles

Trigonometry
A ladder that is 15 feet long is placed so that it reaches from level ground to the top of a vertical wall that is 13 feet high A. Use the law of sines to find the angle that the ladder makes with the ground to the nearest hundredth B. Is more than one position of the ladder ...

physics
When the crampton coal-fired train engine was built in 1852 , its mass was 48.3t ( 1.0 t= 1.0*10^3) and its force capability was rated at 22.4 kN. Assuming it was pulling train cars whose total mass doubled its own was and the total friction on the engine and cars was 10.1 kN...

physics
When the crampton coal-fired train engine was built in 1852 , its mass was 48.3t ( 1.0 t= 1.0*10^3) and its force capability was rated at 22.4 kN. Assuming it was pulling train cars whose total mass doubled its own was and the total friction on the engine and cars was 10.1 kN...

physics
Lol :) thanks , i should have thought of that

physics
According to newtons 1st law , construction workers are warned not to leave their hard hats on the rear window ledge of their cars, explain why?

physics
Sorry i meant 4000 kg is the mass

physics
A jet plane pilot decides to accelerate horizontally. If the thrust of the engine is increased to 50 000 N at a time when the air resistance ( or drag) acting on the 4000kg plane amounts to 30 000 N , what will the planes acceleration be I believe you at the 50 000 and the 30 ...

physics
Thank you so much I understand now !

physics
How much applied force is needed to accelerate a 2.0 kg block of wood at 4.0m/s^2 along a rough table, against a 10 N force of friction?

physics
Thank you for helping me ! It takes me a little bit longer to grasp concepts, i think now the correct answer is it is unbalanced because it accelerates?

physics
Is the net forces balanced because it accelerates steadily in a straight line?.

physics
I have no clue we never covered it in class!

physics
A 1200 kg boat accelerates steadily at 0.05 m/s^2 in a straight line . Are the forces on this boat balanced or unbalanced?

physics
The force of friction is zero?

physics
A woman pushes a refrigerator across the floor at a steady speed of 20cm/s . If she has to push with a horizontal force of 400 N to keep it moving , is the force of friction less than 400 N , 400 N, more than 400 N, why

physics
Thank you so much, i understand a lot more now !

physics
A jet plane is traveling at a constant speed in a straight line in level speed. What does this tell you about the forces acting on it, what forces are acting on it .

physics
thank you bobpursley

physics
A triathlete swims 1200 m due to east followed by 1500 m due northeast (45o). What is the overall displacement? (magnitude and angle). Calculate the displacement with long-hand calculations.

physics
Thanks bobpursely I need this for my Quantitative Biomechanics class

physics
A diver is jumping straight up with 2 m/s from a 15 meter platform. Calculate the maximum height of the diver, the diver’s velocity when reaches the water, and total time to reach the water.

Calculus
A rectangular prism is defined by vectors (2,0,0) (0,9,6) and (0,0,3). Find the volume.

Geometry
The height of the segment from the apex of the cone to the base is 10 feet. The length of the diameter of the circular base is 4 feet. Calculate the volume

Geometry
The height of the segment from the apex of the pyramid to the base is 10 feet. The length of the diagonal of the square base is 4 feet. Calculate the volume

geometry
a ladder is 53 inches. how tall is it in feet and inches

Calculus and vectors
I don't know, I think that it is A-B=C

Calculus and vectors
Explain how the vector C⃗(Going from the head of B⃗ to the head of A⃗) can be written in terms of vectors A⃗ and B⃗ Given the shape in this url: imgur dot com/5nT3V

Calculus and vectors
Please, help I don't understand vectors T.T 1. In the prism, assume all dimensions have different lengths, state the following: a) state 3 equal vectors to DC⃗ b) state 4 opposite vectors to BC⃗ ------------------------------------- Here is the prism below, ...

art history
How would you compare and contrast the northern and southern style temple?

Physics
A athlete in good physical condition can land on the ground at a speed of 12m/s without injury , calculate the max height from which the athlete can jump without injury, assuming the takeoff speed is zero

Physics
A student throws a baseball vertically upward, and 2.8s later catches it at the same level. Neglecting air resistance , calculate the following (a) the velocity at which the ball left the students hand (b) the height to which the ball climbed above the students hand

math
B

Physics
A car is doing a loop-the-loop. The loop has a radius of .4m. Assume the car is starting with the minimum speed it needs in order to stay in contact with the track at all times (at the top of the track, the car is not applying a force to the track). neglect friction. What is ...

geometry
60ft

geometry
120 ft

college algebra
A triangle is bounded by the x-and y-axes and must pass through P(2,2) a.) find the area of the triangle as a function of x (Hint: let C be the point (0,2) and D be the point (2,0). Use the fact that ACP and PDB are similar triangles.) b.) What is the domain of the function ...

college algebra
A piece of pottery is removed from a kiln and allowed to cool in a controlled environment. The temperature (in degrees Fahrenheit) of the pottery after it is removed from the kiln is shown for various times (in minutes) in the following table. Time(min) Temperature (F) 15 2200...

college algebra
A rectangle is bounded by the x-and y- axes and the graph of y = -1/2x + 4. a.) Find the area of the rectangle as a function of x. b.) Complete the following table x area 1 2 4 6 7 c.) What is the domain of this function?

college algebra
A magazine company had a profit of \$98,000 per year when it had 32,000 subscribers. When it obtained 35,000 subscribers, it had a profit of \$117,500. Assume that the profit P is a linear function of the number of subscribers s. a.) Find the function P b.) What will the profit ...

college algebra
Thank you and sorry someone impersonated you.

college algebra
sorry I will resubmit them. Thanks.

physics
If you were asked to design a capacitor in which small size and large capacitance were required, what factors would be important in your design?

physics
A river is moving at 4.0 m/s [s] , and a swimmer swims across it at 1.4 m/s [e] relative to the water. What is the swimmers velocity measure with respect to the river bank

physics
A river is moving at 4.0 m/s [s] , and a swimmer swims across it at 1.4 m/s [e] relative to the water. What is the swimmers velocity measure with respect to the river bank

college algebra
Given f(x)= 3x^2+x-30 and g(x)=x-3 find f(x)-g(x)

college algebra
Find the vertex for f(x)=-5x^2-6x=3

economics
An article in Business Week warned of the dangers of deflation as the collapse of numerous Asian economies was creating worries that Asia might try to “ export its way out of trouble” by oversupplying everything from automobiles to semiconductors. Evidence that ...

Math
A sensor light installed on the edge of a home can detect motion for a distance of 50ft. in front and with a range of motion of 192degree. Over what area will the sensor detect motion and become illuminated?

math
B=1.69 (sqrt (s)+4.45)-3.49 solve for s

Math
4t+14=6t/5+7

Physics!! Help!!!!!
A wire of length L and cross-sectional area A has resistance R. What will be the resistance R_stretched of the wire if it is stretched to twice its original length? Assume that the density and resistivity of the material do not change when the wire is stretched. Express your ...

algrebra
16(5/8x+1/16)x=16(7/16+x) I have no idea how to multiple 5/8 by 16

chemistry
who was the first scientist to identify a nuclear bombardment reaction?

Physics!! Help!!!!!
. A neutral conducting sphere contains a spherical cavity. A point charge +q is located at the |center of the cavity. A. What is the total surface charge on the interior surface of the conductor? B. What is the total charge on the exterior surface of the conductor?

math
the top will have a piece of marble 20 1/2 by 22 bordered by 3 1/4 inches of wood on all four sides. Give the overall dimension of the table top

physics
The angle between the polarizer transmission axis and the plane of polarization of the incoming light is 30 +/- 2 deg. If the incident light intensity Io is 100 W/cm2 what would be the intensity I after the light is transmitted through the polarizer? What would be the percent ...

Precalculus
Consider the equation 7sin^2x - (4sin2^x)/cosx = -1 a) Put the equation in standard quadratic trig equation form. Why is it 7sin^2x - 8sinx + 1 =0?

Precalculus
Which of the following is a solution for the equation 1/485tan^2x = 0? a) pi b) pi/2 c) 485pi d) no solution Which of the following is NOT a solution to the equation 4sin^2x = 1 for 0≤x≤2pi? a) 30 degrees b) 210 degrees c) 150 degrees d) 120 degrees?

Precalculus
Solve the equation (x+3)(x-3) = -9. What are the solutions to the equation if you replace x first with sinx and then with cosx, where 0≤x≤2pi?

Precalculus
Thank you!

Precalculus
Thank you~ May I know how you got 150 degrees? I am so confused when finding the reference angles, whether to subtract or add the degrees.

Precalculus
Sorry, I meant 2sinx - cos^2x = sin^2x for 0 ≤ x ≤ 2π 2sinx - cos^2x = sin^2x Do I change the left side to 2sinxcosx - cos^2x = sin^2x

Precalculus
Determine the solutions to the equation 2sinx − cos2x = sin2x for 0 ≤ x ≤ 2π . How do I start this question?

Math
How can I figure out what the line segment of radical, or Sq root of 17 looks like?

Physic
A cheetah can accelerate at a rate of 8.0 M/S^2. Assuming it starts from rest, what will its velocity be after 3.5 SECONDS?

math
a certain antibiotic redues the number of bacteria in your body by 10% each dse, if 4 doses of the antibiotic are taken, what percent of the original bacterial population is left

math
sam invested \$5000 in a GIC earning 8% compound interest per year, the interest gets added to the amount invested, so the next year sam gets the interest on the interest already earned , as well as on te original amoun, how much will sam's investment be worth at the end of...

math
a student plants a seed, after the speed sprouts the student monitors the growth of the plant by measuring its height every week, the height after each of the first tree wees was 7mm , 20mm, and 33mm, respectively, if this pattern of growth continuesinwhat week will the plant ...

math
determine the 100th term of the arithmetic sequence with t7=465 and t13=219

world religions
In class I got this question any help would be great!! I have no clue how to answer it. If Jesus were human, what does this mean for Christianity and Judaism

chemistry
10 J

science
describe the path that oxygen follows through the human body to reach muscle tissue and describe the path carbon dioxide follows from inside the cell to the outside envrionment

science
what 3 anatomical factors influence a persons vo2max and what 3 internal physiological factors influence a persons vo2max

math
A catering company has 15 customer orders during its first month, for each month afterward, the comopany has double the number of orders than the previous month. How many orders in total did the company fill at the end of its first year ?

math
a ball is dropped from a height of 3m and bounces on the ground . At the top of each bounce, the ball eaches 60% of its previous height. Calculate the total distance travelled by the ball when it hits the ground for the fifth time

Math
The 13th termof an arithmetic sequence is 61 and the 20th term of the squence is 82. Calculate the sum of the first 25 terms of the sequence

Math
the 12th term in a geometric sequence is 49, and the 14th term is 2401 . Find the 15th term

algebra
The first 1/5 of a mile is \$1.50. For every additional 1/5 of a mile is 25 cents. If Marc has \$3.75, at least how far can he go? P.S. I need an inequality.

physics 2B
This ties in with chemistry actually. They give you Temperature, Pressure, and Volume. Convert temperature to Kelvins (add 273) and convert your volume to Liters. Use R constant 0.0821. Plug into the ideal gas law of PV=nRT and solve for the moles of the He atom (thats n). ...

Chemistry
Thanks so much! That makes alot more sense now. The figures really helped out.

Chemistry
Not to mention the conversions! But thanks a million. :) I got a range of an average of 0.064 nm to 0.45 nm. Considering concept wise though, do the units of nm make sense for an atoms diameter? That's not visible right?

Chemistry
True or False: The diameter of most atoms will be between 0.05 nm and 0.3 nm. I think its false (I don't think there even is an average diameter for atoms...), but I can't find any reliable sources to back up my hunch. Help please...

math
Matthew is riding a ferris wheel at a constant speed of 10km/h. The boarding height for the wheel is 1m, and the wheel has a radius of 7m. What is the equation for the function that describes Matthews height in the terms of time, assuming Matthew starts at the highest point on...

Math
The diameter of a car's tire is 60cm . While the car is being driven , the tire picks up a nail .How high above the ground is the nail after the car has travelled 1km

Biology
explain the process of adaptive radiation, and how are reproductive barriers important to speciation

World religions
For this project for school we have to represent the noble eightfold path ( right view) to canadian society , but i am so stuck , i don't really know anything that would make sense, any help would be great

chemistry
Calculate the pH of each of the following solutions. (a) 0.300 M propanoic acid (HC3H5O2, Ka = 1.3 10-5) (b) 0.300 M sodium propanoate (NaC3H5O2) (c) pure H2O (d) 0.300 M HC3H5O2 and 0.300 M NaC3H5O2

chemistry
The Ksp for silver sulfate (Ag2SO4) is 1.2 10-5. Calculate the solubility of silver sulfate in each of the following. A)water B)0.14 M AgNO3 C)0.33 M K2SO4 the answer in mol/L

math
how do u do lost digits?? my son has to do this for homework and we are both stuck on how to do this.

Statistics
The average hourly wage of employees in a large nationwide industry is \$12.96. Assume the variable is normally distributed, with a standard deviation of \$4.46. In a randomly selected sample of 10,000 such employees, how many of them (correct to the nearest hundred) would you ...

statistics
570 people were in a survey and 124 people said yes. What proportion of people said yes to 1 d.p

chemistry
Calculate the pH of a 0.063 M (C2H5)2NH solution (Kb = 1.3 10-3).

Chemistry
Calculate the molar heat of neutralization in kJ/mol of the reaction between HA and BOH given the following information: The temperature change equals 8C, 50 mL of 1 M concentration of Acid 50 mL of 1 M concentration of Base Heat capacity of the calorimeter is 6.5 J/C. ...

math
prove these identies sin^2+tan^2=sec^2-cos^2 sin^2 sec^2 +sin^2=tan^2+sin^2

math
An urn contains 5 red marbles, 4 blue marbles, and 3 green marbles. A marble is selected at random and then, without replacing the first marble, a second marble is selected at random. What is the probability of selecting a green marble and then a red marble?

English
What are the differences between the characters Johnny and dally, in the story The Outsiders by S.E. Hinton?