# physics please HELP !

128,227 results, page 45

### AP Physics B

Through a pipe of diameter 15.5 cm , water is pumped from the Colorado River up to Grand Canyon Village, on the rim of the canyon. The river is at 564 m elevation and the village is at 2096 m . At what minimum pressure must the water be pumped to arrive at the village? The ...

### physics

Calculate the work required to be done to stop a car of 250 kg moving at a speed of 18km/hr? answer is right or not please check Mass =250 kg Velocity = 18kg = 18 x 1000/60 x 60 = 5 m/s KE = ½ mv x v = ½ x 250 x 5 = 125 x 5 = 625 J Therefore the counter back this force we ...

### Chemistry- URGENT please HELP

NH4NO3(s)+H2O(l)→NH4NO3(aq) ΔH = +25.7 kJ. What is the final temperature in a squeezed cold pack that contains 49.0g of NH4NO3 dissolved in 125 mL of water? Assume a specific heat of 4.18J/(g⋅∘C) for the solution, an initial temperature of 28.5∘C, ...

### Physics Help, Please

A flatbed egg truck is in a drag race. The truck is carrying a 450 lb. crate of eggs in the back. The coefficients of friction between the crate and the truck bed are μs = 0.9 and μk = 0.4. What is the maximum acceleration the truck can have without the eggs sliding ...

### Floating Point Notation

Help me please, anyone understand this topic. For example 1011 1110 in Floating Point = ? and hot to accomplish this. Please!

### Chemistry-please help

Please show me the calculation steps. How do I prepare 10%w/w Hydrochloric acid from 37%w/w Hydrochloric acid? The density of 37%w/w HCl is 1.19g/ml. Thank you.

### math URGENT!!

the midpoints of the sides of a triangle are (1,1),(4,3),and (3,5). find the area of the triangle. please answer and show how u did it step by step please!!!!

### chemistry project please help really need it

help me out in choosing a topic for my project it should be anyhow related to chemistry help me please

### Calculus Help Please!!!

Use implicit diff. to find dy/dx of each of the following. In the following x,y and (a) are all variables. Show step by step please! Thank you! 1) y^2 = x^2+a^2 2) y^2+ay = x^2+ax+a^2

### Math Please Check

Please check my answers! Thank you! Simplify the following expressions. Collapse “x” terms, and/or simplify fractions and exponents. 1.) (12/5) / (36/20) = 4/3 2.) x^13*x^3 = x^16 3.) x^4 / (x^2)^3 = 1/x^2 4.) x^-3 / x^2 = x^-5 5.) (x^2-8x+16) / (x-4) = x-4 6.) x^(-1/3) / ...

### perfect number

I need two perfect numbers. For my activity,I should submit it tomorrow please help me. I need now. Please

### perfect number

I need two perfect numbers. For my activity,I should submit it tomorrow please help me. I need now. Please

### Physics (again, sorry)

A swimmer maintains a speed of 0.15 m/s relative to the water when swimming directly toward the opposite shore of a straight river with a current that flows at 0.75 m/s. (a) How far downstream is the swimmer carried in 1.5 minutes? (b) What is the velocity of the swimmer ...

### physics

A dockworker loading crates on a ship finds that a 20 kg crate, initially at rest on a horizontal surface, requires a 73 N horizontal force to set it in motion. However, after the crate is in motion, a horizontal force of 50 N is required to keep it moving with a constant ...

### Physics please help

How do I convert a distance time graph into a velocity time graph. I am given a distance time graph with three curves but i am not sure how to calcualte the area of them to get the velocity time graph.

### physics

The physics of satellite motion around Jupiter. A satellite of mass 2.00 x 104 kg is placed in orbit 6.00 x 105 m above the surface of Jupiter. Please refer to the data table for planetary motion included in this lesson. a) Determine the force of gravitational attraction ...

### math

in which set would 2/5, 15/36, and 24,12 be placed and why set A = 1/4, 7/25, 5/8, 3 3/5 set B = 2/3, 4/7, 11/12, 1/9, 34/18 Please note that we don't do students' homework for them. Once you have come up with a response to these questions, please re-post and let us know what ...

### Physics

A car's initial velocity of 13.5 m/s accelerates at a rate of 1.9 m/s^2 for 6.2 s. Then, it accelerates at a rate of -1.2 m/s^2 until it stops. 1) What is the car's maximum speed? 2) What is the total time from the start of the first acceleration until the car is stopped? 3) ...

### Physics, science,

I'm desperate Please help 2. A bird, starting from rest, accelerates at 3 m/s2 north for 5 seconds. It then sees the rest of its flock and turns due east accelerating from its previous speed to 20 m/s in 2 seconds. A. What is the velocity of the bird after the initial leg (due...

### Physics Help Please

particle 1 of charge q1 = 6.60×10-5 C and particle 2 of charge q2 = 3.30×10-4 C are fixed to an x axis, separated by a distance d = 0.100 m. Calculate their net electric field E(x) as a function of x for the following positive and negative values of x, taking E to be ...

### Physics

You use a rope to slowly pull a sled and its passenger 45 m up a 20∘ incline, exerting a 125-N force on the rope. How much work did Earth do on the sled for the trip in Part B? The answer for part is -5630 J I'm not sure what to do. I tried -5630 J * 9.8 then I tried ...

### Physics

At its highest point the pendulum is 1.2 meters off the ground and has a gravitational potential energy of 62 Joules. If the gravitational potential energy is 10 Joules at its lowest point. What is the pendulums kinetic energy at this point? Please help!

### physics

physics - asa, Tuesday, September 18, 2012 at 1:25pm can yu help me thanks in advanec. imageshack . us /photo/ my-images//593/questionpb.png/

### ap history

what did the great awakening, intercolonial trade and the rise of the colonial assemblies have in common? Please note that we don't do students' homework for them. Once you have come up with your response, please repost, and someone here will be happy to critique your thinking...

### chemistry

Please calculate the solubility of calcium sulfate in 0.010 mol/L calcium nitrate at SATP. This very question has been bugging me all weekend. Can some one please solve this quesiton it would really be appreciated.

### Maths

hello Can someone please help me with solving simultanaous equations using graphs My problem is that i don't know how to plot them on the actal graph and nor I know how to plot the gradient withing this paticular situation I need help with some steps please MY IGCSE's are ...

### Help me please!!!

Hi, I have an assignment in which i am supposed to identify a good citizen in my community. i need to write an essay on why he/she deserves that title. The problem is that i have just moved to this country so i don't know many of the people here and what they do. what do u ...

### English- American Lit

Hi can you please help me with John Cheever's Enormous Radio. I'm having trouble understanding what it was in the story that helped create our national identity of the time (1947) is it the new radio that Jim bought his wife? please help me.

### English- American Lit

Hi can you please help me with John Cheever's Enormous Radio. I'm having trouble understanding what it was in the story that helped create our national identity of the time (1947) is it the new radio that Jim bought his wife? please help me.

### history

show how the role of the federal government was viewed by different groups at different times in the 20th century. i don't even know how to begin answering this question. i'm so stuck. can someone please give me enough ideas to get started? please help me thanks a lot

### english

please help me with this. it's an essay question that i'm really stuck on based on romeo and juliet. please help!!! thanks what are some decisions Romeo had to make that could possibly decide his fate, and how are his decidion-making skills in the first two acts of the play?

### English

Hello. Please help me with the verb "purpose". Is it possible to use it in the sentence "The latest terrorist attack is purposed to intimidate the world" or is it used in a different meaning or a different form (if yes, will you please give a short example). Thank you very much.

### cal3 please help!

Use Lagrange multipliers to find the max/min values of the function f(x,y)=xy subject to the constraint: x^2/8+y^2/2 =1 so I compare the gradient vectors of both f(x,y) and the constraint: <y,x>=L<x/4,Ly> resulting in y=Lx/4 and x=Ly now how do i solve for L x and ...

### PLEASE HELP GEOMETRY

When constructing inscribed polygons and parallel lines, how are the steps similar? a protractor is used to take measurements four right angles are created a compass is used to copy an angle **** there are no similarities I think its c, but it might be b. PLEASE HELP <3

### Physics

Please check these answers[my letter choice is in CAPS]: 1. In the steps of the scientific method, what is the next step after formulating and objectively testing hypotheses? A. interpreting results b. stating conclusions c. conducting experiments d. making observations and ...

### Medical Physics

A block is acted on by a force that varies as (2.8*10^4 N/m)x for 0<=x<=.21m, and then remains constant at 5880 N for larger x. 1. How much work does the force do on the block in moving it from x = 0 to x = 0.30 {m}? 2. How much work does the force do on the block in ...

### Physics.

A mass of m1 = 12 kg is placed on an incline with an inclination angle of 50 degrees, a coefficient of kinetic friction of 0.16, and a coefficient of static friction of 0.89. m1 is tied to a rope which runs parallel to the incline and runs over a pulley to a hanging mass of m2...

### Physics Please help!

the coefficient of static friction between the coffee cup and the roof of a car is 0.28, If the maximum acceleration the car can have without causing a cup of coffee (on the top of the car) to slide is 2.7 m/s^. What is the smallest amount of time in which the person can ...

### Physics Please help!

the coefficient of static friction between the coffee cup and the roof of a car is 0.28, If the maximum acceleration the car can have without causing a cup of coffee (on the top of the car) to slide is 2.7 m/s^. What is the smallest amount of time in which the person can ...

### Physics- Elena please help!!!!

A centrifuge in a medical laboratory rotates at an angular speed of 3500 rev/ min. When switched off, it rotates through 41.0 revolutions before coming to rest. (a) Find the angular speed in rad/s. (b) Find the displacement in radians. (c) Find the constant angular ...

### physics

a grandfather clock is designed to have a pendulum which swings a mass at the end of the chain in a horizontal circular motion. the pendulum is designed to swing 7 degrees off of the vertical. the chain is 1.50 meters long and the maximum tension in the chain is 12.0 N. ...

### Physics

For the object in the preceding problem, what magnitude torque is necessary to give the object an angular acceleration of 1.5 rad/s^2 a) along the x-axis? b) along the y-axis? c) along the z-axis (perpendicular to the page, passing through the origin)? Help please! Use the ...

### Physics

A horizontal spring(k= 86.2 N/m) is placed on a countertop and is compressed a distance of 36.3 cm. A 103.5 g object is placed at the end of the spring. The coefficient of kinetic friction between the object and countertop is measured to be .47. What acceleration will the ...

### physics

A coin is placced 12.0 cm from the axis of a roatating turntable of variable speed. When the speed of the turntable is slowly incraeased, the coin remains fixed on the turntable until a rate of 50 mph is reached at which point the coin slides off. What is the coefficent of ...

### Physics

A block of mass m lies on a rough plane which is inclined at an angle è to the horizontal. The coefficient of static friction between the block and the plane is ì. A force of magnitude P is now applied to the block in a horizontal direction, towards the plane. Show that the ...

### Science Physics

Ms. Sue could you please explain this to me. Imagine you need to deliver a piano over three steps. A longer ramp translates into less force necessary to raise the piano's height than a shorter ramp would require. Calculate the percentage smaller a force would be required using...

### Physics Urgent please help

A figure skater stands on one spot on the ice(assumed frictionless) and spins around with her arms extended. When she pulls in her arms, her moment of inertia decreases to 3/4 of the initial value. Assume that her spin angular momentum is conserved. What is the ratio of her ...

### TO ALL STUDENTS

If you are able to help another student with his/her homework, please do. But if you cannot, please don't post anything. If a teacher sees a post has been answered, he or she might think the original student doesn't need help anymore. Thanks. =)

### Algebra

Hi. I need help on this homework problem. I don't know where to start of how to do this. Will you please help me? Find the value of digit A if th give-digit number 1243bis to be divisible by both 4 and 9, with A not equal to B. I don't understad this at all. I need your help ...

### Chemistry

Phenol (abbreviated HOPh) is a weak acid with a Ka= 1.29 X 10^-10. What is the pH of a mixture made by mixing 100.0 ml of a 0.700 M solution of phenol with 70.0 ml of a 1.00 M solution of NaOH? Help please and please show work... I'm so confused.

### Chemistry-please help!

When sucrose is fermented to produce ethanol why is it not possible to obtain a final solution containing more than 10-15% ethanol? Does this have to do with azeotropes? However, I thought this was possible? I am confused, please help.

### Chemistry-please help!

When sucrose is fermented to produce ethanol why is it not possible to obtain a final solution containing more than 10-15% ethanol? Does this have to do with azeotropes? However, I thought this was possible? I am confused, please help.

### PERSON!!!!!

I have no money at all no credit card or checks or anything! So can someone please tell me where to get a free background check or free record check?? I really need this please!!

### science

Please help me with this. why is it that blood pump away from the heart under pressure? why is it necessary for blood to be oxygenated before pumped to the cells? Please this question is under the topic circulatory system.

### college algebra--need help please!!

solve the equation in the real number system. 2x^4-23x^3+75x^2-88x+28=0 What are the real solutions of the equations? please show work. I do not know how to work this at all

### Math

Hi I really need help. I don't know even how to figure these two questions out so if you could help me, please. Is (–4, 10) a solution to the equation 10 – 5x = y? Explain your answer. Describe the pattern in the table using an equation. x|y 1|15 2|25 3|35 4|45 Please help...

### Algebra please help

A grocery store sells snacks by weight. A six ounce bag of mixed nuts costs $3.60. Predict the cost of a two ounce bag. Please help answer

### Algebra 1- Please help whenever you get the chance

Graph the function shown by the table. Tell whether the function is linear or nonlinear. x|y 0|1 1|2 2|5 3|10 i'm sorry, i don't have the graph, but is their any way this could work without it? Please help. Thanks

### please give me a site or answer!!!!

description of the population statistics LOCATION in South Carolina already found the age and race just having trouble with the location statistics please help!!!!!!

### Government Help Please

A major feature of newly created federal system of government is that it gained its power from ____ 1) the people 2) the national government 3) the state governments 4) the executive branch of government Please help.. thanks

### Geometry (Please check my work)

Find the image of O (-2,-1) after two reflections, first across the line y=-5, and then across the line x=1. I believe the answer should be (-1,-6) Can someone please confirm?

### Algebra

3. What would be the simplest way to solve the system? y=1/2x 2x + 3y = 28 A. Graphing B. Substitution***** MY ANSWER! C. Elimination D. Distributive 4. What is the solution of the system? y=-3x 2x + 3y = 6 A. (2,6) B. (-1,3) C. (-2,6)*****MY ANSWER! D. (1.5, -4.5) Please help...

### ALL STUDENTS, PLEASE READ

Please remember these things: 1. This is a homework help website; please put your subject (math, science, English, or ??) in the subject line to make it faster for each teacher to find those questions in his/her areas. Even better is if you put your specific subject, such as "...

### Phsyics Plz Help

How many grams of carbohydrate does a person of mass 75 kg need to metabolize to climb five flights of stairs (15 m height increase)? Each gram of carbohydrate provides 17.6 kJ of energy. Assume 10.0% efficiency—that is, 10.0% of the available chemical energy in the ...

### Physics Help Please

A horizontal spring with a spring constant of 200.0 N/m is compressed 25.0 cm and used to launch a 3.00 kg block across a frictionless surface. After the block travels some distance, the block goes up a 32 degree incline that has a coefficient of friction of 0.25 between the ...

### Chemistry

Following question I need help with part b) Please verify my answer for part a) too if possible. Consider the following reaction for silver tarnishing: 3Ag2S(s) + 2Al(s) -> 6Ag(s) + Al2S3(s) a. State the oxidation number for each element in the reaction. 3Ag2S(s) + 2Al(s...

### Physics Help Please

a) On the Acme W&W company production line, parts have to be transported 100 m by conveyor belt to a machine area. The parts move at a constant speed of 2.5 m/s. How much time does it take to move a part 100 m? b) On the same conveyor belt as described in problem a), the part ...

### Physics - Can you plz help!

a) a flashlamp bulb is marked '2.5V,0.30A' and has to be operated from a dry battery of e.m.f 3.0V for the current p.d. of 2.5V to be produced across it. Why? b) ow much heat and light energy is produced by a 100W electric lamp in 5 minutes? c) what is the resistance of a 240V...

### Physics

I have performed an experiment of simple harmonic motion and the values I got Mass(g)Distance (m) 200 0.438 250 0.398 300 0.345 350 0.312 400 0.297 450 0.281 500 0.259 I would like to know how to calculate the spring constant... since I have been having weird values, if ...

### physics

If the car has a mass of 0.4 kg, the ratio of height to width of the ramp is 13/125, the initial displacement is 1.9 m, and the change in momentum is 0.87 kg*m/s, how far will it coast back up the ramp before changing directions? tinypic(dot)com(slant)r(slant)10dunx3/7 I get ....

### Physics

A football is kicked off with an initial speed of 63 ft/s at a projection angle of 45 degrees. A receiver on the goal line 67 yd away in the direction of the kick starts running to meet the ball at that instant. What must be his minimum speed (in feet/second) if he is to catch...

### please help physics!!!!

Two dynamics carts are placed end to end. Cart 1 (1.2 kg) is stuck to cart 2 (1.8 kg). Cart 1 is pushed with a force of 18.9 N (west),causing cart 1 to push cart 2 forward. Ignore the force of friction. Calculate the acceleration of each cart Calculate the force that cart 1 ...

### physics- help me please

The pressure at the bottom of a glass filled with water (ρ = 1000 kg/m3) is P. The water is poured out and the glass is filled with mercury (ρ = 13.6 ✕ 103 kg/m3). The pressure at the bottom of the glass is now which of the following? a)equal to P b)smaller ...

### Physical Science

Objects accelerated to relativistic speeds....live shorter or grow bigger? Please note that we don't do students' homework for them. Once YOU have attempted to come up with a response to YOUR questions, please re-post and let us know what you think. Then someone here will be ...

### english

i need help writing a "i am" metaphor poem. The format is 10 lines of I am metaphors and the 11th line is what you are like i am annoying or i am blonde or something. PLease help it is due tomorrow! Someone here will be happy to give you feedback on what you write. Please ...

### 7th grade

My textbook question is: Please look at page 38, Figure 2.6: "How do historians know Cartier traveled these particular routes? Where might they have found supporting historical evidence. The picture is just a map with the guys travels. (arrows and lines ect) Please help!

### science

How ionising radiation affect the cell, DNA and can lead to tumours /leukaemia? nothing too complex please note form will be fine, in which I can use it in my explanation. if you can please put it in your own words as I find it much easier to understand and explain in my ...

### SCIENCE

How ionising radiation affect the cell, DNA and can lead to tumours /leukaemia? nothing too complex please note form will be fine, in which I can use it in my explanation. if you can please put it in your own words as I find it much easier to understand and explain in my ...

### Language Arts

which of the following citations in a work cited page uses proper MLA style Please help do today! the examples are Paul, Smith. The Night on the river. New York: Penguin 1987.Print please write it out for me how it should look thanks.

### Math - Please Check My Answers

Please help me with the following two problems: Find the greatest possible error for each measurement. 512 m A. 0.5 m C. 0.5 cm B. 5 m D. .005 cm I think the answer is A. Is this correct? Find the greatest possible error for the given measurement if it is to the nearest 10 ...

### Physics (Please)

I'm confused and am hoping someone could help me understand energy can neither be created nor destroyed... great... so in physics classes we can set up problems and stuff were KEo + PEo = KE + PE Energy intial equals energy final sense energy is conserved but then when ...

### physics. please help

A worker pushes a 820 N crate with a horizontal force of 345 N a distance of 24 m. Assume the coefficient of kinetic frictin between the crate and the floor is 0.22. a) How much work is done by the worker on the crate? b) How much work is done by the floor? c) What is the net ...

### physics--please help

When only the front wheels of an automobile are on a platform scale, the scale balances at 7.8 kN; when only the rear wheels are on the scale, it balances at 5.5 kN. What is the weight of the automobile? How far is its center of mass behind the front axle? (The distance ...

### Chemistry

Hi, please can someone tell me if this is the right number of significant figures. 8.1 x 10 to the power of -3 would have 2 sig fig 910 would have 3 175.0 would have 3 please can some tell me if I've got this right Also how would I report each of the following measurements ...

### Physics

I got a few questions that I need to be checked please? Why does a brick weigh 1 kilogram. Explain. -Would it be cause there are not other forces acting on it that's why it weighs 1 kilogram? Why do lurch foward when a bus slows down? What law is this? -Is it because the bus ...

### PHYSICS 1

When a pitcher throws a curve ball, the ball is given a fairly rapid spin. A 0.15 kg baseball with a radius of 3.7 cm is thrown with a linear speed of 41 m/s and an angular speed of 37 rad/s. Assume that the ball is a uniform, solid sphere. (b) Calculate how much of its ...

### Physics

A driver has 50kg mass, and drives from a high board. On entering the water the driver travels vertically downward and comes to rest in a vertical distance of 5 m. The average resistance force is acting on the driver during the motion to rest in the water is three times her ...

### physics- please help

A 65 kg bungee jumper leaps from a bridge. She is tied to a bungee cord that is 11m long when unstretched, and falls a total of 30m . Part a) Calculate the spring constant of the bungee cord assuming Hooke's law applies. part b)Calculate the maximum acceleration she ...

### College Physics PLEASE HELP

A spring stretches 0.150 m when a 0.30 kg mass is hung from it. The spring is then stretched an additional 0.100 m from this equilibrium point and released. Determine a). the spring constant, k, b). the maximum velocity of the mass, c. ) the maximum acceleration of the mass, d...

### college physics

If I travel to Mexico and buy a 55g gold braclet for 20 dollars and take the braclet and submerge it in water starting out with 50cc and after it is submerged in the water it is 52.8cc. What is the buoyant force on the braclet? I also need to know if the braclet is real gold. ...

### Physics

5. If a wave has a wavelength of 20m and a speed of 100 m/s, what is the period of the oscillation? v = wavelength / period 100 = 20 / period 100*20 = periodperiod = 20 / 100 2000 s = period OR period = 20 / 100 period = 0.2 s I don't know which one is correct, please help?!

### physics help please

You want to use a windmill to generate electricity for your home. You decide to use Earths magnetic field which has a horizontal component B=10^-4 T to an induce emf. You design a conduction loop with 200 turns and surface area of 0.1m^2. The rod is 0.5m wide. On the day you ...

### PHYSICS PLEASE HELP

A 60.8-kg skateboarder starts out with a speed of 1.84 m/s. He does 90.8 J of work on himself by pushing with his feet against the ground. In addition, friction does -278 J of work on him. In both cases, the forces doing the work are non-conservative. The final speed of the ...

### physics

There is a great deal of ice floating on the ocean near the north pole. If this ice were to melt due to global warming, what would happen to the level of the oceans? A.Rise B.Fall C.Remain the same water is slightly more dense than water, but when the ice melts it will have ...

### physics-please help!

The total cross-sectional area of the load-bearing calcified portion of the two forearm bones (radius and ulna) is approximately 2.5 cm2. During a car crash, the forearm is slammed against the dashboard. The arm comes to rest from an initial speed of 80 km/h in 4.2 ms. If the ...

### physics for scientists and engeneers I

A 0.145-kg baseball pitched horizontally at 27 m/s strikes a bat and is popped straight up to a height of 43 m. If the contact time between the bat and the ball is 2.35 ms, calculate the average force [exerted by the bat on the ball] during contact. [Let the positive axis lie ...

### Physics check my answer please

The atmosphere on Mars is almost all carbon dioxide (CO2), and has a pressure of about 6.9×102 Pa, much less than that of Earth. At −22°C (a warm day on Mars), what is the mass of one cubic meter of the atmosphere? (Assume the atmosphere is completely CO2.) I got 0.020...

### Physics

A 95 gram piece of metal is heated to 98°C and placed into 200mL of water insulated at 20°C. If the equilibrium temperature is 27.20, find: The heat gained by the water. calories: _________ The specific heat of the metal. cal/(g°C): ________ Hint: 1 mL water has a mass of 1...

### PHYSICS PLEASE HELP!

You need to open a heavy door that's 40 inches wide. Instinctively, you push near the edge that's the farthest from the hinges. If instead, you had pushed at a point only 10 inches in from the hinges, how much harder would you have had to push to open the door at the same ...