130,975 results, page 64

1. ### physics

Two boats start together and race across a 42 km wide lake and back. Boat A goes across at 42 km/h and returns at 42 km/h. Boat B goes across at 21 km/h, and its crew, realizing how far behind it is getting, returns at 63 km/h. Turnaround times are negligible, and the boat ...
2. ### physics

I am not sure how to setup this problem. I posted it earlier and "BOB PURSELY" responded we are happy to critique your thinking. I have know idea how to solve this problem or even where to start. Please help!!! A tetherball leans against the smooth, frictionless post to which ...
3. ### Physics

I am not sure how to setup this problem. I posted it earlier and "BOB PURSELY" responded we are happy to critique your thinking. I have know idea how to solve this problem or even where to start. Please help!!! A tetherball leans against the smooth, frictionless post to which ...
4. ### physics

If you rub a piece of PVC pipe with some wool and touch the PVC to Aluminum foil. Will the PVC be charged after rubbing it with wool?? Will the aluminum be charged? Finally can the PVC cause the aluminum to move. Please explain (hint: can the PVC give charge to the aluminum?) ...

An insulating sphere of mass m and positive charge q is attached to a spring with length h and spring constant k_s and is at equilibrium. An infinitely long wire with positive linear charge density lamda is placed a distance l away from the charged mass at equilibrium as shown...
6. ### Physics

A 1.0 e 3 kg elevator carries a maximum load of 800.0 kg. A constant frictional force of 4.0 e 3 N retards the elevator's motion upward. Waht minum power in kilowatts, must the motor deliver to lift the fully loaded elevator at a constant force of 3.00 m/s? I have no idea how ...

If I went tubing with my little sister, and I have a larger mass, why would we both reach, in terms of energy, the bottom of the hill at the same time; Originally I thought because we would both be accerlerating at the same rate but that doesn't explain the energy part does it...
8. ### Physics

A fuzzy die (m = 0.2 kg) hangs from the ceiling of a car. When the car accelerates forward along a horizontal road, the die swings backward so the the string supporting it makes an angle of 4 degree with the vertical. 1) What is the acceleration of the car? HINT: We're not ...

A 33kg child named Lindsey runs as fast as she can and jumps onto the outer edge of a merry-go-round. The merry-go-round is initially at rest and has a mass of 78kg and a radius of 2.20m. Lindsey's linear velocity was 9 m/s at the moment she jumped onto the merry-go-round. ...

Four 20-ohm resistors are connected in series and the combination is connected to a 20 V emf device. The current in any one of the resistors is: A) .25 A B) 1.0 A c) 4.0 A D) 5.0 A E) 100 A My answer: A R= 20 + 20 + 20 + 20 =80 V= IR 20/80=I I=.25 A battery with an emf of 24 V...

A 3.70kg box is sliding across the horizontal floor of an elevator. The coefficient of kinetic friction between the box and the floor is 0.470. Determine the kinetic frictional force that acts on the box when (a) The elevator is stationary. (b) The elevator is accelerating ...
12. ### physics

What is the horizontal velocity of the pencil? the ? is you are standing in the aisle of a bus that travels along a straight road at 100km/h, and you hold a pencil still above your head. then relative to the bus,the velocity of the pencil is km/h and relative to the road,the ...
13. ### physics

Hi! could any help me please, thank you. 1.An object is placed 17.8 cm from a first converging lens of focal length 13 cm. A second converging lens with focal length 24 cm is placed 10 cm to the right of the first converging lens. (Take the direction to the right to be ...

A proton, traveling with a velocity of 6.8 × 106 m/s due east, experiences a magnetic force that has a maximum magnitude of 8.6 × 10-14 N and direction of due south. What are the magnitude and direction of the magnetic field causing the force? If the field is up, then enter ...

A flat circular coil with 97 turns, a radius of 4.04 10-2 m, and a resistance of 0.528 Ω is exposed to an external magnetic field that is directed perpendicular to the plane of the coil. The magnitude of the external magnetic field is changing at a rate of ΔB/Δt...
16. ### Algebraic expressions

Please can you give me an algebraic expression for the following I am litterally racking my brain on this, please Rita has \$315 in the bank. This amount is three times the amount that Fred has. How much does Fred have? Use f to represent Fred's amount
17. ### Algebraic expressions

Please can you give me an algebraic expression for the following I am litterally racking my brain on this, please Rita has \$315 in the bank. This amount is three times the amount that Fred has. How much does Fred have? Use f to represent Fred's amount

Please check my answer thanks :) True or False If an enrollee uses more services then first thought they would per the PPOM calculation then the plan would show a loss for that period I said True
19. ### Algebra-I really need help, please?

I have to solve sqrt(2x-7) >=5 answers would be x>=16 x>=7/2 7/2<=x<=16 x<=16 I don't get this concept at all and I have 20 of these kinds of problems for homeowrk-can someone direct me how to start or give me an example or just help please? I really need to ...

Please check to make sure I did these correctly, so confusing. Thank you. Rename each fraction as a terminating or repeating decimal 13/20 .65 1/3 0.3333333333333333 2/9 0.2222222222222222 5/12 0.4166666666666667 1/16 0.0625 Rename each mixed number as a terminating or ...
21. ### Computer Science

I need help with this question please! Please write me step by step instructions or how should I begin the problem. Thank you for your time ;) Write a function that takes an array and returns true if all the elements in the array are positive, otherwise, it returns false.

Maria wants to cover the box shown below with paper.Which of the following could be the dimensions of the paper so that Maria has enough to cover the box, including the ends, with a little left over? Shape: Rectangular Prism Length:8 in Width: 2 in Height: 2 in A) 8 in x 4 in ...
23. ### Chemistry

How many grams of H2O are required to react with excess CaC2 to produce 23.0 g of C2H2 according to the following equation? CaC2 + 2H2O -> Ca(OH)2 + C2H2 a.4.5 b.15.9 c.31.8 d.1.766 I think this equation works out by multiplying 2 moles by the molar mass of H2O. Please ...
24. ### Physics

The figure shows a pV diagram of a gas for a complete cycle. During part bc of the cycle, 1190 J of heat flows into a system, and at the same time the system expands against a constant external pressure of 7.00 × 104 Pa as its volume increases from 0.0200 m3 to 0.0800 m3. ...
25. ### physics

a person stands a distance of 0.300 meters from the right end of a 2.00 meter long uniform platform that is supported by two posts, one at each end. The board has a mass of 20.0 kg and the person's mass is 75.0 kg. a. determine the force exterted on the board by the post on ...

A duck has a mass of 2.8 kg. As the duck paddles, a force of 0.05 N acts on it in a direction due east. In addition, the current of the water exerts a force of 0.15 N in a direction of 60° south of east. When these forces begin to act, the velocity of the duck is 0.12 m/s in ...

he thermal conductivity of concrete is 0.80 W/m-C° and the thermal conductivity of wood is 0.10 W/m-C°. How thick would a solid concrete wall have to be in order to have the same rate of flow through it as an 8.0 cm thick wall made of solid wood? (Assume both walls have the ...

Please check my answer thank you :) Dr Hannah places a stethoscope to a seven - year old child's chest. The lungs reveal basilar rales. Which method is Dr Hannah using to perform the physical exam? A. Auscultation B. Palpation C. Percussion D. Visualization My answer is C

Please check my answer thank you Cardiology is the study of the heart. Which of the following terms describes the foundation upon which the medical word is built that usually relates to the body organ involved ? A. Prefix B. Suffix C. Root D. Combining form My answer is Root (c)

Complete hydrolysis of 25 mM ethyl acetate in an enzyme (i.e., esterase)-catalyzed reaction is carried out in a 40 mM NaCl solution buffered by 0.2 M Tris-Cl, pH 9.1. What is the pH at the end of the reaction? (For Tris base, which is the abbreviation for Tris (hydroxymethyl) ...

please help me with that as soon as any bady can processExpression - this method should take a String in the format: "integer [[+-*/] integer]*]" Your method should then process this expression and return the result as an integer. You must solve this problem using ONLY tools ...
32. ### pre calc

The population of a Midwestern city decays exponentially. If the population decreased from 900,000 to 800,000 from 2003 to 2005, what will be the population in 2008? Please help I got 670,422 and the computer marked it wrong i then tried rounding it to 671000 but it was still ...

A block of wood, with density 828 kg/m3 , has a cubic shape with sides 0.340 m long. A rope of negligible mass is used to tie a piece of lead to the bottom of the wood. The lead pulls the wood into the water until it is just completely covered with water. What is the mass of ...
34. ### Physics

A metal tank with volume 3.10 L will burst if the pressure of the gas it contains exceeds 100 atm. (a) If 11.0 mol of an ideal gas is put into the tank at a temperature of 23.00C, to what temperature can the gas be warmed before the tank ruptures? You can ignore the thermal ...
35. ### Physics (College)

A student rides her bicycle home from physics class to get her physics book and then heads back to class. It takes her 21.0 min to make the 12.8 km trip home and 13.0 min to get back to class. Calculate her average speed for the round-trip. Answer must be converted to km/h I ...
36. ### Planning (URGENT)

Describe 5 positive activities, events, or experiences in your life and why was it positive. Please help me. What does it mean when it talks about positive experiences? So would meeting my best friend be a positive experience? Please give me examples. So I can understand what ...
37. ### Physics

1An object is thrown upward at an initial velocity and caught at the same level as it was thrown. What should the maximum height be if the hang time is 6.4? (please report numerical value to 2 decimal places- unit will not be necessary to report) 2An object is thrown upward at...

Segment DF bisects angle EDG. Find FG. segment EF is n+9 segment FG is 4n-6 Please Help me on this one question! I'd really appreciate it! Thank You :)!

I need help because I don't understand how to solve this equation. 37. x/a - 1 = y/b for x So... does it mean solve for x? 39. V = 1/3 * pi * radius^2 * h for h So... does it mean solve for h? As you can see, I am really confused. Please help.
40. ### Physics ~ work shown, pls help!

A proton is moving in a circular orbit of radius 11.8 cm in a uniform magnetic field of magnitude 0.232 T directed perpendicular to the velocity of the proton. Find the orbital speed of the proton. Answer in units of m/s. I came up with .118/2.83x10^-7 and it was incorrect. (...

Why is the following situation impossible? A librarian lifts a book from the ground to a high shelf, doing 20.0 J of work in the lifting process. As he turns his back, the book falls off the shelf back to the ground. The gravitational force from the Earth on the book does 20.0...
42. ### Physics: Capacitance of Capacitor

Capacitor A and capacitor B both have the same voltage across their plates. However, the energy of capacitor A can melt m kilograms of ice at 0 °C, while the energy of capacitor B can boil away the same amount of water at 100 °C. The capacitance of capacitor A is 8.4 μF...
43. ### Physics

A ball with mass m = 0.210 kg and kinetic energy K1 = 2.97 J collides elastically with a second ball of the same mass that is initially at rest. After the collision, the first ball moves away at an angle of = 30.6° with respect to the hori- zontal, as shown in the figure. ...
44. ### Physics

A ball with mass m = 0.210 kg and kinetic energy K1 = 2.97 J collides elastically with a second ball of the same mass that is initially at rest. After the collision, the first ball moves away at an angle of = 30.6° with respect to the hori- zontal, as shown in the figure. ...
45. ### Physics

A ball with mass m = 0.210 kg and kinetic energy K1 = 2.97 J collides elastically with a second ball of the same mass that is initially at rest. After the collision, the first ball moves away at an angle of = 30.6° with respect to the hori- zontal, as shown in the figure. ...
46. ### Physics

A ball with mass m = 0.210 kg and kinetic energy K1 = 2.97 J collides elastically with a second ball of the same mass that is initially at rest. After the collision, the first ball moves away at an angle of = 30.6° with respect to the hori- zontal, as shown in the figure. ...
47. ### Physics

1. How much energy is required to be removed to lower the temperature of a bottle of drinking water (280mL) from 22°C to 4°C? The density of water is 1.0g/mL here are the equations we can use: (-m1)(C1)(ΔT1)=(m2)(C2)(ΔT2) Q=mcΔT Q=mL There might be others I am...

helloo, i want to ask if you have any answers or any websites to do with the advantages of of electronic displays rather than a paper display? why is it better?? please help meeeeeeeee! thnkyou One thing that comes to mind quickly: Electronic displays can change font size ...

please check my answer thanks :) Dr Bob make an erronrous entry in the record. Three years later nurse Sue noticed the mistake and corrected it Why was this correction improper !. Too much time passed to correct the record 2. The corretion was made by the nurse not the doctor ...
50. ### Algebra

Can someone please help me??!!! i don't get this at all!! can you explain it step by step please? :) Ellen and Allen have a lemonade stand. One sixth of their earnings E must be used to pay for supplies for the next day. Each child then gets to keep half of the remaining money...

how to work out partial fraction decomposition when given 1/x(x^2+1) and 2x-1/(x+4)(x-3) if you could give me an idea of the formula and what changes i need to make to the formula when the denominator changes that would help and please use idiot speak because the text books ...

The manager of a an out-patient surgical unit shares patient information with a pharmaceutical representative to assist the rep in putting together a survey could assist with the FDA approval for a new drug to combat serious post-op infections. Is the manager involved in an ...
53. ### Intermediate Algebra

solve equation (x+1)(x-2)=54 Eric stated that the solution would be (x+1)=54==> x=53 or (x-2)=54==> x=56 However at least one of these solutions fails to work when substituted back in the orginial equation. Why is that? Please help Eric to understand better, solve the ...
54. ### maths

NOTE: before you answer this question, please be aware that there aren't meant to be any full stops after the '2' or the 'i=0'. Also the underscores '-' represent how the following number is meant to be a lower case number. The ^ represents root numbers. PLEASE HELP ME Expand ...

Two speakers, A and B, are emitting identical, synchronized (in-phase) sound waves at 240kHz. A person standing a point C hears a relatively loud sound. She then starts walking towards point D, and notices the sound gets quieter, reaching a minimum when she arrives at D. The ...

Two speakers, A and B, are emitting identical, synchronized (in-phase) sound waves at 240kHz. A person standing a point C hears a relatively loud sound. She then starts walking towards point D, and notices the sound gets quieter, reaching a minimum when she arrives at D. The ...

Two speakers, A and B, are emitting identical, synchronized (in-phase) sound waves at 240kHz. A person standing a point C hears a relatively loud sound. She then starts walking towards point D, and notices the sound gets quieter, reaching a minimum when she arrives at D. The ...
58. ### Physics Plans Project (11th Grade)

I'm doing a physics project where I have to find plans for a device and then build it and type a report demonstrating the physics behind it. However, the materials can't cost more than \$75 total. I'm having trouble finding any plans, especially ones that are interesting, ...

60. ### HISTORY

Explain what traces the rise of Japan from an isolated society to a major industrial and imperial power. Please help. I need to write a paragraph on this. As you know, don't write me a paragraph. But please answer my question, without links, enough so there is enough ...

The Everton college store paid \$1859 for an order of 49 calculators. The store paid \$11 each for scietific calculators. The others, all graphing calculators, cost the store \$55 eaach. How many of each type of calculator ws ordered? Please answer in detail so that I can see ...

Two cars are moving. The first car has twice the mass of the second car but only half as much kinetic energy. When both cars increase their speed by 3.41 m/s, they then have the same kinetic energy. a) What is the original speed of the first car? b)What is the original speed ...

Two cars are moving. The first car has twice the mass of the second car but only half as much kinetic energy. When both cars increase their speed by 3.41 m/s, they then have the same kinetic energy. a) What is the original speed of the first car? b)What is the original speed ...
64. ### physics

light travels from ethanol intro crown glass. what's the brewster angle in this situation? illustrate your answer with a light ray diagram. what's the signifcance of this angle of incidence? n1=1.36for ethanol nR=1.52 for crown glass tanangleB=nR/ni =1.52/1.36 =1.12 (48.2 ...
65. ### Physics

A plate falls vertically to the floor and breaks up into three pieces, which slide along the floor. Immediately after the impact, a 200g piece moves along the x-axis with a speed of 2.00m/s and a 235g piece moves along the the y axis with a speed of 1.50m/s. The third piece ...
66. ### Physics

A plate falls vertically to the floor and breaks up into three pieces, which slide along the floor. Immediately after the impact, a 200g piece moves along the x-axis with a speed of 2.00m/s and a 235g piece moves along the the y axis with a speed of 1.50m/s. The third piece ...
67. ### physics

resistors of 30 ohms and 60 ohms are connected in parallel and joined in series to a 10 ohm resistor. the circuit voltage is 180 volts I need to find 1)the voltage of the parallel circuit 2)the resistance of the complete circuit 3)the voltage across the 10 ohm resistor 4) the ...
68. ### physics

resistors of 30 ohms and 60 ohms are connected in parallel and joined in series to a 10 ohm resistor. the circuit voltage is 180 volts I need to find 1)the voltage of the parallel circuit 2)the resistance of the complete circuit 3)the voltage across the 10 ohm resistor 4) the ...
69. ### Physics

Can someone please provide me with some insight on this question? A pair of scissors is being used to cut a string. Does each blade of the scissors have the same angular velocity (both magnitude and direction) at a given instant? yes no Give your reasoning. The answer is no. ...

A distant galaxy is simultaneously rotating and receding from the earth. As the drawing shows, the galactic center is receding from the earth at a relative speed of uG = 1.90 106 m/s. Relative to the center, the tangential speed is vT = 3.00 105 m/s for locations A and B, ...
71. ### physics- please respond !

A 0.130kg baseball pitched at 35.5 m/s is hit on a horizontal line drive straight back at the pitcher at 50.5 m/s . Part a: If the contact time between bat and ball is 4.25×10^−3 , calculate the magnitude of the force (assumed to be constant) between the ball and bat. ...

A 0.130kg baseball pitched at 35.5 m/s is hit on a horizontal line drive straight back at the pitcher at 50.5 m/s . Part a: If the contact time between bat and ball is 4.25×10^−3 , calculate the magnitude of the force (assumed to be constant) between the ball and bat. ...
73. ### Physics

Occasionally, huge icebergs are found floating on the ocean's currents. Suppose one such iceberg is 114 km long, 31.3 km wide, and 194 m thick. (a) How much heat in joules would be required to melt this iceberg (assumed to be at 0 °C) into liquid water at 0 °C? The density ...
74. ### PHYSICS!!

I've tried this problem again and again using conservation of momentum and energy but I am not having any luck: A ball of mass 0.300kg that is moving with a speed of 8.0m/s collides head-on and elastically with another ball initially at rest. Immediately after the collision, ...
75. ### PHYSICS HELP

Suppose the aliens watching the show are on the surface of Mars. Mass of Mars: 6.42 x 10^23 kg Radius of Mars: 3.394 x 10^6 m Calculate; A) the weight of a 40.0 kg alien on Mars B) the weight of 40.0kg alien on earh Earth-sun distance:1.50x10^11m Mars-sun distance: 2.28 x10^11...
76. ### Social Studies 8R - Paragraph Check

Please check my paragraph to see if it's good. If there any detials I should add please let me know. Also please let me know if there any grammar errors. Obama Win When Barack Obama was re-elected I was ecstatic. Obama is a really good president and he deserve to be president ...
77. ### physics

Would someone check my thinking please. A solid sphere (mass, r, and moment of inertia given) is rotating at a given angular speed. Friction is constantly applied at the 'equator' of the sphere, and brings it to rest in 3s. Find the force. I worked out the torque, and then ...
78. ### Physics

A box, with a weight of mg = 25 N, is placed at the top of a ramp and released from rest. The ramp measures 4.40 meters horizontally and 3.50 meters vertically. The box accelerates down the incline, attaining a kinetic energy at the bottom of the ramp of 54.0 J. There is a ...
79. ### Physics

An electron with a horizontal speed of 4.0 * 10^6 m/s and no vertical component of velocity passes through two horizontal parallel plates. The magnitude of the electric field between the plates is 150 n/c the plates are 6.0 long A) calculate the vertical component of the ...

The antenna broadcasts radio signals at the resonant frequency of the tank circuit. Suppose that a certain tank circuit in a shortwave radio transmitter has a fixed capacitance of 1.8 x 10-11 F and a variable inductance. If the antenna is intended to broadcast radio signals ...

An aircraft has a take-off speed 180km/h and has length 250m from the start just before take-off a serious snag is detected in the engine and the aircraft failed to take-off. There is a wall at a distance 'd' = 230m ahead of the take-off point. The pilot applies breaks which ...
82. ### Mathematics

A Pendulum 45cm long swings through a vertical angle of 30degrees. Find the distance of the altitude through which the pendulum bob rises. (I couldn't find this answer either :\ but can anyone please please help me! And if you can, can you also write the equation on how you ...
83. ### Intermediate Algebra

Solve using elimination method. If the system has no system or infinite number of solutions, state this. Please show all work. I need to show how I came about my answer. I need this as soon as possible please. I would appreciate any and all help!! 2x+2y=20 2x-2y=4
84. ### Math

Suppose a population is sampled and the sample mean is 16.8. The sample standard deviation is 6.0 I am to assume the sample is larger than 30) and the sample size is 65. How do I calculate 95% and 98% confidence intervals. State which interval wider and why please. How would I...
85. ### PLEASE COULD SOMEONE HELP ME OUT

Two long straight aluminum wires, each of diameter 0.30mm, carry the same current but in opposite directions. They are suspended by 0.50m long strings...If the suspension strings make an angle of 3.0 degree with the vertical, what is the current in the wires? Thank you......

My problem: A swimmer travels from the south end to the north end of a 30.0 m pool in 15.0 s and makes the return trip to the starting position in 19.0 s. What is the average velocity for the second half of the swim? My answer: 1.60 m/s to the south Please check! I will really...

A woman with a genetic disease marries a man who does not carry the disease. It is not possible for their children to carry the disease. The disease must be a) sex - linked b) recessive c) dominant d) cause by an extra chromosome I think the answer is recessive, can someone ...
88. ### Chemistry

Ytterbium, atomic number, 70 is the first element in the periodic table to have the first four shells full. work out the number of electrons in the fourth shell/ level of ytterbium? Please show all working out with no abbreviations and please help
89. ### calculus

answer the questions about the following function f(x)= 10x^2/x^4+25 a. is the point (-sqrt 5,1) on the graph b. if x=3, what is f(x)? what point is on the graph of f? c. if f(x)=1, what is x? what points are on the graph? d. what is the domain of f? e. list the x-intersepts? ...
90. ### PHYSICS

A truck is traveling at 16 m/s to the north. The driver of a car, 500 m to the north and traveling south at 25 m/s, puts on the brakes and slows at 3.5 m/s2. Where do they meet? please help!! Let the truck position be X1 and the car position X2, measured along the same north-...
91. ### Deciding on a H.S. Science Course

I'm currently a sophomore, and I need to plan a science course for next year. Do you know if colleges require physics? Would a college prefer to see physics on my transcript in oppose to Environmental Sciences or Astronomy? Thanks!!
92. ### Physics

"if u could do this physics problem thatd be super. A coach is hitting pop flies to the outfielders. If the baseball (m = 145 g) stays in contact with the bat for 0.04 s and leaves the bat with a speed of 50 m/s, what is the average force acting on the ball?"
93. ### physics

A physics student drops a book into a shaft 250m deep,where the average mine temperature is 5 degrees celsius.Show that the sound of the book striking the bottom is heard after 7.82 seconds
94. ### Science - Physics

When a projectile is fired horizontally, which of the components of its motion is (A) motion at constatnt speed (B) uniformly accelerated motion (C) If the initial velocity of the projectile is increased, what effect will this have on the time it takes the projectile to fall ...
95. ### Physics

A vertical spring with a spring constant of 450 N/m is mounted on the floor. From directly above the spring, which is unstrained, a 0.30 kg block is dropped from rest. It collides with and sticks to the spring, which is compressed by 3.0 cm in bringing the block to a momentary...
96. ### Physics

Can you please help with this problem. I don't know how to solve it at all. A uniform solid disk with a mass of 32.3 kg and a radius of 0.464 m is free to rotate about a frictionless axle. Forces of 90.0 N and 125 N are applied to the disk. (a) What is the net torque produced ...
97. ### physics

Vroom-vroom! As soon as a traffic light turns green, a car speeds up from rest to 50.0 mi/h with a constant acceleration of 8.40 mi/h·s. In the adjoining bike lane, a cyclist speeds up from rest to 20.0 mi/h with a constant acceleration of 11.5 mi/h·s. Each vehicle maintains...
98. ### Physics

TURNTABLE SOLUTIONS A gyroscope consists of a uniform disc of mass radius M= 1 kg and radius R= 0.3 m . The disc spins with an angular speed ω= 400 rad⋅s-1 as shown in the figure below. The gyroscope precesses, with its axle at an angle 30∘ below the ...