130,813 results, page 17

1. ### Physics

Two forces, F1 and F2, act on the 5.00 kg block shown in the drawing. The magnitudes of the forces are F1 = 69.0 N and F2 = 24.5 N. What is the horizontal acceleration (magnitude and direction) of the block? F1 is pointing at the top left corner of the box forming a 65 degree ...

How high could a .5kg basketball be launched by a spring, if the spring is compressed by 0.2m and has a constant of 200N/m? How fast would the basketball be going just as it left the spring?

How high could a .5kg basketball be launched by a spring, if the spring is compressed by 0.2m and has a constant of 200N/m? How fast would the basketball be going just as it left the spring?
4. ### physics

1. a force of 30n with a direction of 35 degrees northwest acts on point p. Find: a) the northward component on the force b) the westward component of the force Please show work. Thanks!
5. ### physics

The relative Density of an alloy is 65.(a) find the mass of a solid alloy cube of side 20cm.(b) what vol of the alloy has a mass of 13kg? Please explain in details

A motorcycle has a constant acceleration of 2.13 m/s2. Both the velocity and acceleration of the motorcycle point in the same direction. How much time is required for the motorcycle to change its speed from (a) 24.0 to 34.0 m/s, and (b) 54.0 to 64.0 m/s
7. ### Physics (ASAP)

Please, I need help with this problem A cue stick applies an average force of 66 N to a stationary 0.17 kg cue ball for 0.0012 s. What is the magnitude of the impulse on the cue ball? Thank you

A 1.35 kg mass is suspended from a spring with a spring constant of 189.0 N/m. The spring is attached to a rod which oscillates vertically at a frequency f. For what value of the frequency f will the system resonate?

an athlete stretches a spring an extra 40.0 cm. how much energy has he transferred to the spring, if the spring constant is 5286.0 N/m? Us= 1/2kx^2 =1/2(5286.0)(.40)=1057.2 J Thanks!
10. ### Physics

A block of mass 4.11 kg is hanging from a rope. The tension in the rope is 23.5 N, pulling upward on the block. What is the magnitude and direction of the acceleration of the block? F=ma 23.5=4.11a The result was 5.72 and was not correct. Please help!
11. ### Physics ideal gases

Would someone check my thinking please. PVT of an ideal gas (nitrogen) are all given. I've used PV=nRT rearranged to get the number of moles. Then, U= 3/2nRT to get the internal energy of the sample. Am I on the right track? Thanks.
12. ### Physics

In 1989, Carl Lewis established a world record when he ran the 100 meter dash in 9.92 seconds. What was his average speed(in m/s) for the race? Remember to include your data, equation, and work when solving this problem. I am not sure how to do this problem. Please help!!
13. ### Physics Help!

Sorry I've tried 3 different ways to answer this and all have been wrong, please help me out! The moment of inertia of a 1.1 kg bicycle wheel rotating about its center is 0.15 kg*m^2 What is the radius of this wheel, assuming the weight of the spokes can be ignored?
14. ### Physics

1) Is it accurate to describe the physical universe as composed of only matter and energy? 2) How is it possible that only 92 elements are found in the natural world but there are millions of different types of molecules? I really have no clue about these questions. Please help!!
15. ### physics - electricity

Does the size of a 1,5V cell(battery) affect the internal resistance of a circuit containing: 3 different size batteries,multimeter,connecting wire,a light bulb resistor.How do i set up this experiment.I'm really lost, please help. Thank you in advance
16. ### physics

PLEASE HELP !!!!!!Find the acceleration reached by each of the two objects shown in figure below if the coefficient of kinetic friction between the 7.00 kg object and the plane is 0.250. img411.imageshack.us/img411/5841/p449.gif I keep getting 3.9=a
17. ### SCIENCE(PHYSICS)

A TRAIN IS MOVING ON A STRAIGHT TRCK AND TRAVELS AT A SPEED OF 72KM/HR AND PASSES A POLE IN 3 SECONDS. FIND THE TIME TAKEN TO PASS A BRIDGE OF LENGTH 540m. PLEASE SOLVE THE QUESTION AND ANSWER IT AS I WAS NOT ABLE TO ANSWER IT.

A 1.67-kg block of aluminum at 21.7°C is to be melted and reshaped. How much heat must flow into the block in order to melt it? use the following values: For copper: c_copper=0.386 kJ/kg.K T_fusion=1359 K L_fusion=205 kg/K
19. ### Physics

Sam tosses a ball horizontally off a footbridge at 4.3 m/s. How much time passes after he releases it until its speed doubles? Can someone please explain the correct equation to use thoroughly and help me to find the correct answer?!
20. ### physics

A major-league pitcher can throw a ball in excess of 36.2 m/s. If a ball is thrown horizontally at this speed, how much will it drop by the time it reaches a catcher who is 17.0 m away from the point of release? I got -1.08 for the answer but my book is saying its wrong! ...

In the final stages of the landing process, a spaceship decelerates at a constant rate of 5.3 m/s2 heading towards the Earth. A 3kg lamp is hanging straight down, attached to the ceiling of the ship cabin by a chain. What is the tension in the chain?

a Geiger ionization chamber contains 60 cubic cm of air and records 500 mR/min. calculate (a). the current produce by the chamber (b). the total number of ion pairs produced per hour of exposure. please answer, thank you!,

Here's a neat trick. If your average ceramic bowl has a mass of 200 g, what is the difference in Newtons between the weight of the bowls on the top of her head before and after she does the trick? Details and assumptions The acceleration of gravity is −9.8 m/s2.
24. ### physics

A race car moving at 157km/hr decelerates at -7.00 m/s^2 to a speed of 75.0km/hr A) how long did this take? B) how many meters did the car travel during this deceleration? I attempted this problem many times and i don't seem to get the correct answer please show all work thank...
25. ### phySICS NEED HELP ASAP

Sally the bug has an initial speed of 20.0cm/s. She then accelerates at 8.00cm/s^2 for 5.00s. calculate sallys total displacement? which i did and got 200 cm Displacement during the 5th second? can you please help and show all work
26. ### NEED HELP PHYSICS!!!

An airplane is flying in a horizontal circle at a speed of 117 m/s. The pilot does not want his centrifugal acceleration to exceed 6.8g (that is, to be more than 6.8 times the acceleration of gravity). What is the minimum radius (in meters) of the circular path? PLEASE LEAVE ...
27. ### Physics

A golf ball is struck with a five iron on level ground. It lands 91.4 m away 4.20 s later. What was (a) the direction and (b) the magnitude of the initial velocity? angle=tan-1(Ry/Rx) for direction R=(Rx^2+Ry^2)^(1/2) I cannot figure out the variables and if the x and y ...
28. ### Physics

A 1200 kg sedan is traveling at 10m/s when it is hit from behind by a 1000 kg convertible. The bumpers of the cars crush and lock. Their combined speed just after the crash is 16 m/s. What is the velocity of the convertible before the collision? Please show your work.

Two parallel wires are carrying 5A and are separated by 2.0 m. if the currents are in opposite directions, what is the magnitude of the magnetic field halfway between them? Someone please help as I can't figure out the question. Thanks, They are asking for the field between ...

Please finish these questions so I can check my answers. All my answers are at the bottom. Adding and subtracting mixed numbers. Please finish these questions. The answer must be reduced to lowest terms! 1. 3 2/5 + 6 1/5= 2. 4 2/5 + 1/10= 3. 2 3/12 + 2 3/6= 4. 5 3/9 + 2 1/3= 5...
31. ### to KEEGAN

Please use "Post a New Question" and then be sure to ask a question! Please note that we don't do students' homework for them. Our tutors try to give you the information to help you complete your assignment on your own. Then once YOU have come up with a response to YOUR ...

I don't want someone to do this for me-I'm just totally lost and don't even know where to start-I'm totally lost on this one- the earth is surrounded by an electric field with a strenth of 100 N/C at the surface. Its electric properties are the same as a point charge located ...

Sorry to bug again but can someone check my answers please thank you. 1. Simplify the expression 3w-10w A. 13w B. -7w C. -7 D. 7w 2. Y+2y+3z A. 2y+3z B. 3y+3z C. 2y^2+3z D. 6yz 3. 6r+r-5r A. 2r B. 1r+r C. 0r D. 7r-5r 4. 5x+2(x+6) A. 7x+6 B. 7x^2+12 C. 7x+12 D. 7x (x+6) 5. -3m+...
34. ### maths

1. A die labelled A has one face marked 1, one face marked 2 and the other four faces marked 3. A die labelled B has four faces marked 2 and two faces marked 3. The dice A and B are thrown. Calculate the probability is 5. I got 18/36 2. There are 12 boys and 20 girls in a ...
35. ### how come no one is helping on physics questions!!!

every physics helpers are not getting any responses. can someone help on physics questions pleases???

How do you determine the ymax? I know you have to use Q which I have values that were given to me as well as vo values but I am not sure what to do with these values.
37. ### Physics (vectors)

Could you please help me with this exercise? Thanks. Adding and substracting vectors Solve for the unknown variables: (a) (a, b) + (3, 0) = (6, 7) (b) (11, c) + (d, 5) = (-12, −3) (c) (5, 5) + (e, 4) = (2, f) (d) (-1, −3) − (5, g) = (h, 2)
38. ### Physics (vectors)

Could you please help me with this exercise? Thanks. Adding and substracting vectors Solve for the unknown variables: (a) (a, b) + (3, 0) = (6, 7) (b) (11, c) + (d, 5) = (-12, −3) (c) (5, 5) + (e, 4) = (2, f) (d) (-1, −3) − (5, g) = (h, 2)
39. ### physics

please show me how to do this in steps. A track star in the long jump goes into the jump at 12 m/s and launches herself at 20.0degrees above the horizontal. What is the magnitude of her horizontal displacement? (assume no air resistance and that Ay= -g = -9.81 m/s^2) thanks :)
40. ### chemistry/physics Urgent!!

how do i calculate the substrate concentration needed relative to Km to produce a rate relative to Vmax which is 0.1 x Vmax ?? I think i need to manipulate the michaelis menton eq but when i do it im left with [s] in the amount please help lib
41. ### Physics

Please Help!! A baseball clears a 3m tall wall positioned 120 m from home plate. The ball leaves the bat 1.2m above the ground and 45degrees above the horizontal. How fast was it going when it left the bat?

A spider sits on its web, undergoing simple harmonic motion with amplitude A.What fraction of each cycle does the spider spend at positions with x>0.75A? Hint: Use the analog of uniform circular motion.

A spider sits on its web, undergoing simple harmonic motion with amplitude A.What fraction of each cycle does the spider spend at positions with x>0.75A? Hint: Use the analog of uniform circular motion.
44. ### Physics

A particular guitar string is supposed to vibrate at 220 , but it is measured to vibrate at 230 . By what percent should the tension in the string be changed to correct the frequency? I have been working for 7 hours of hw! Please help!

A 8.6 kg board is wedged into a corner and held by a spring at a 50.0° angle, as the drawing shows. The spring has a spring constant of 186 N/m and is parallel to the floor. Find the amount by which the spring is stretched from its unstrained length.
46. ### Physics

Can someone please show me step by step how to normalize e^-5x in the interval (0, infinity)? I have read a lot of different books etc but need it explained to me in plain English or showed to me step by step because I am just not getting it. Thank you
47. ### Physics help someone please

An 800 g, 40.0 cm diameter hollow sphere is rolling along at 4 m/s when it comes to a 25 degree incline. Ignoring any friction, how far along the incline does it roll before it stops and reverses its direction?

What is the potential halfway between two point charges spaced 1 mm apart if q1=10 micro coulombs and q2= -5 micro coulombs? Attempt at solution: no idea but need to get this right our homework is graded

A diffraction pattern forms when light passes through a single slit. The wavelength of the light is 680 nm. Determine the angle that locates the first dark fringe when the width of the slit is each of the following. (b) 1.20 x 10^-6 m
50. ### Physics

A 13.0 -kg box is released on a 33 degree incline and accelerates down the incline at 0.20 m/s^2 Find the friction force impeding its motion? Can someone please take me through this problem step by step? Thank you so very much
51. ### Physics of Vehichle

A 1400 kg car rounds a curve of 57 m banked at an angle of 14 degrees If the car is traveling at 98 km/h, will a friction force be required? If so, in what direction? May someone please walk me through this problem step by step? Thank you

Two blocks each of mass 3.38 kg are fastened to the top of an elevator as in the figure. (b) If the strings can withstand a maximum tension of 87.8 N, what maximum acceleration can the elevator have before the first string breaks?
53. ### physics

In co2 laser, the co2 vibrates when it collides with nitrogen atoms instead of getting excited to next level.Why? why is this vibration after collision is not seen in Helium-neon laser?please explain me

Three objects are moving along a straight line as shown in the figure. Taking the positive direction to be to the right, what is the total momentum of this system? Pos ---> 5.00 m/s, 8.00 kg Neg <--- 4.00 m/s, 15.00 kg Pos ---> 2.00 m/s, 3.00 kg A) -14 kg m/s B) +106 ...
55. ### Physics

A rock is thrown into a railroad car standing on a level frictionless track. If the rock has a mass of ms = 1.100 kg and is tossed with a velocity v = 6.3 m/s, how far up will the car go (mc = 5.400 kg) before stopping? Please explain
56. ### Physics

A camera falls from a blimp that is 744 m above the ground and rising at a speed of 15.5 m/s. Find the maximum height reached by the camera with respect to the ground. The acceleration of gravity is 9.8 m/s^2. Answer in units of m. PLEASE HELP SOON

Calculate the molar enthalpy of solidification when 10.00KJ of energy are lost as 30.00g water are frozen at 0*C. i divided 30/18.02 =1.664 mol then, divided 10KJ/1.664mol =6.010 KJ/mol Am i correct? Thank you!
58. ### Physics

Suppose a 300–g kookaburra (a large kingfisher bird) picks up a 84.0–g snake and raises it 2.30 m from the ground to a branch. How much work did the bird do on the snake? I know that W=deltaPE, and PE=mgh. I keep getting 1046.64. Please help!
59. ### physics pls help

Please can someone show me how to go about this problem? The X-Y plane is illuminated by an electric field of strenght given as E=(24î + 60j + 70k) N/C; the flux through a 1.5m² potion of the illuminated plane is
60. ### College physics

Please help me... I have no idea where to begin...A tone of 4000 Hz is being played on a tuning fork. You run toward the tuning fork at 5 m/s. What frequency do you hear? Take the speed of sound to be 343 m/s.
61. ### Physics

How much heat energy is needed to change 0.25kg of water at 100°C to steam at 100°C? Show your work. Please don't give me the answer, I just need help figuring out how to find the answer. Thanks!
62. ### Physics

How much heat energy is needed to change 0.25kg of water at 100°C to steam at 100°C? Show your work. Please don't give me the answer, I just need help figuring out how to find the answer. Thanks!
63. ### Physics (PLEASE CHECK WORK)

For safety in climbing, a mountaineer uses a nylon rope that is 50m long and 1.0cm in diameter. When supporting a 90kg climber, the rope elongates 1.6m. Find its Young's modulus This is what I have so far, I am getting the wrong answer. Can you please fix my mistake? (Studying...
64. ### physics

A 1500-kg car coast in neutral down a 2.0degrees hill. The car attains a terminal speed of 20.0 m/s. The question is:how much power must the engine deliver to drive the car on a level road at 20.0 m/s?? Help me out please!!

Hello! I'm having a bit of trouble trying to solve this physics problem. I'm not sure which equations to use or where or how to plug my variables: Robin Hood wishes to shoot an arrow through the open window of a tall castle wall. The window is 16m meters above the ground and ...
66. ### physics

Given the amplitude of a wave and the wabelength how to you find the period? The problem then goes on and asks me how to find the speed which I know how to do I just don't know how to find the period... Please show me how to do and the formulas to use thanks for the help
67. ### physics

A 400g glider moving to the right at 2 m/s collides elastically with a 500g glider moving in the opposite direction at 3 m/s. find the velocity of each glider? please show work so i can understand it! thanks

An oscillating block-spring system has a mechanical energy of 5.1 J, an amplitude of 0.81 m, and a maximum speed 1.6 m/s. Find the spring constant k of the spring. What is the mass of the block? What is the frequency of oscillation?

1. If 31 waves pass by a point in 1.7 s, what's the frequency? my answer: 18.2 Hz 2. if a crest with an amplitude of 7cm interferes with a trough with an amplitude of 10 cm, the resulting wave has an amplitude of: my answer: -3
70. ### physics

can anyone help me in this question please A particle of mass 27 g and charge 32 µC is released from rest when it is 79 cm from a second particle of charge −22 µC. Determine the magnitude of the initial acceleration of the 27 g particle. Answer in units of m/s 2 .
71. ### physics

A wire has a resistance of R. What will the wire's resistance be if it is stretched to four times its original length without changing the volume of the wire? (Express in terms of R.) R=V/I; 4R=V/I; R=V/(I/4) I think this is right? help please.
72. ### physics

please tell me if these are correct A track star in the long jump goes into the jump at 12 m/s and launches herself at 20.0 deg above the horizontal. What is the magnitude of her horizontal displacement? (Assume no air resistance and that Ay= -g = -9.81 m/s^2) i got 9.2 m ...

Would changing the frequency of a wave cause a change in amplitude? I would say only if the wave velocity remains the same because if the frequency increases, vibrations increase and then amplitude would decrease, correct? If I had a wave diagram will 4 complete waves showing ...

Please someone have mercy this is a test grade and I have no idea what to do ! A force of 200 N is being exerted on a blocki, which has a mass of 10 kg and is on 30 degrees inclined plane. The force is acting up the plane and parallel to it. The coefficient of friction between...
75. ### English

Posted by rfvv on Thursday, December 16, 2010 at 3:21am. {At a restaursant} For hear or to go? Is this for here or to go? It's for here, please. It is to go, please. (Are the expressions above all grammatical? What is the meaning of 'is to' in 'It is to go, please.'? Does it ...
76. ### Physics - HELP! PLEASE

The problem is from fundamentals of physics 9th edition by halliday. Here is a free download of the book since I couldn't post the graph (I had to write out link since site doesn't allow links to be posted): tripplew period sendspace period com/file/shrz0x I am having trouble ...
77. ### Force between Charged Spheres (Physics 11th Grade)

What is the force between two small charged spheres that have charges of 2 x 10^-7 and 3 x 10^-7 if the distance of r is 30 cm. I think you use Force = the constant of K multiplied by the product of the charges divided by the square of the distance again. If you plug in the ...
78. ### physics

just wondering if anybody have any suggestions for a physics project (anything that deals with physics)??? thanks Research the Klien-Fogleman wing and its advantages over conventional wing shapes.
79. ### Physics

Find the final velocity of the two balls if the ball with velocity v2i = -19.5 cm/s has a mass equal to half that of the ball with initial velocity v1i = +26.8 cm/s. PLEASE HELP IVE TRIED EVERYTHING!!!
80. ### physics

i cant solve this problem i need for help please through how many does a point on the earth's surface move in 6h as a result of the earth's rotation ? what is the speed of a point on the equator ? take the radian of the earth to be 6370 km thank you
81. ### physics

i cant solve this problem i need for help please through how many does a point on the earth's surface move in 6h as a result of the earth's rotation ? what is the speed of a point on the equator ? take the radian of the earth to be 6370 km thank you
82. ### Physics

A 9.00 V storage battery is connected to three resistors, 4.25 Ω, 11.0 Ω, and 21.0 Ω, respec-tively. The resistors are joined in series. Calculate the equivalent resistance can someone answer this please?
83. ### Physics

One student generates a short, loud sound of wavelength 0.7576 m. Another student, who is 100 m away, hears the sound exactly 0.300 s later. What is the frequency of this sound? Please help
84. ### physics

Assuming 100% transfer of energy in the system, please calculate maximum KE (Kinetic Energy) that the rocket has if the rocket were to again a height of 25 meters. Rocket mass = 0.5 kilograms, and gravity = 9.8 m/s^2

A body of mass 7.5kg is to be pulled up along a plane which is inclined at 30degree to the horizontal. If the efficiency of the plane is 75 %, what is the minimum force required to pull the body up the plane?

Please somebody do you know any websites that have virtual place value blocks for making decimals. Please make suer i can acctually make the decimal on the websites. Lastly make sure it s a websites that i can stay on for as longt as i want without the website saying that ...

Posted by Mary on Monday, September 24, 2007 at 10:11pm. A cube is located with one corner at the origin of an x, y, z, coordinate system. One of the cube's faces lies in the x, y plane, another in the y, z plane, and another in the x, z plane. In other words, the cube is in ...
88. ### Math

Check answer PLEASE!! Kevin wants to calculate the value of the expression below. -17 + 3 Which shows an equivalent way kevin could write this expression? (A.) -(17 + 3) B. -(17 - 3) C. (-3 + 17) D. (-3 - 17) Please help as soon as possible!! I have no one to help me and i don...
89. ### Algebra

PLease ,Please ,Please help me solve this problems #1 Since x = 3y-4, -3(3y-4)+4y = -3 now just solve for y and then x #2 Since x = 4+4y, -(4+4y) = 4y=-4 or something Again, solve for y, then x

List a repeating decimal that is equal to an integer. I have 0.999 because if you divide it by 9's its equal to 1, 999/999=1 Also I thought of -0.999 that is equal to -1 But I can't think of another one can you please help ? Please

How do you determine the ymax? I know you have to use Q which I have values that were given to me as well as vo values but I am not sure what to do with these values.
92. ### Physics

Derive a formula for the maximum speed v of a simple pendulum bob in terms of g, the length L, and the maximum angle of swing theta. I don't know how to go about this, I thought to use T = 2pi*sqr(L/g) and since F=MA, I divide A by time and . . . but I know this is completely ...
93. ### physics

A 2.00 kg aluminum block and a 5.20 kg copper block are connected by a light string over a frictionless pulley. They sit on a steel surface, where Î¸ = 28.0°. Determine the sum of the magnitudes of the forces of friction acting on the blocks._____________N I don't ...
94. ### PHYSICS-stuck

These are the troublesome questions. What is the average velocity between 0.6 h and 1 h? A. + 0.4 km/h B. + 1.25 km/h C. + 1.66 km/h D. + 2.5 km/h The other question is below. What is the object's displacemnt between 0.4 h and 0.6 h? A. -0.75 km B. +0.25 km C. +0.75 km D. +1.0...
95. ### physics

an ideal monatomic gas is allow to expand slowly until its pressure is reduced to exactly half its original value. By what factor those the volume changes if the pressure is (1)isothermal (2)adiabatic. Please is the answer suppose to be a calculation or an explanation

NOTE: 1 MJ = 106J. One of the most powerful cranes in the world, operating in Switzerland, can slowly raise a load of 6000 tonne to a height of 8 m. (1 tonne = 1000 kg) The acceleration of gravity is 9.81 m/s2 . How much work is done by the crane? Answer in units of MJ
97. ### Physics

The coal car for a train has a mass of 1796 kg when it is empty. The track exerts a friction force of 3132. What force should the be exerted on it by the locomotive, to produce an acceleration of 1.3? (please report the numerical value to 2 decimal places- units are not to be ...
98. ### physics

A person whose mass is m = 60.5 kg steps on a mechanical bathroom scale placed on an inclined plane that makes the angle α = 31.7° with the horizontal. What is the reading on the scale? For this question I used the formula FN=mgcostetha= 60.5x9.8xcos31.7 but the answer ...
99. ### Physics

When a 34-m-long metal pipe is heated from 13 °C to 39 °C, it lengthens by 2.56 cm. Determine the linear expansion coefficient. I tried to start by taking the difference of temperature times the length of the pipe and finally divide 2.56 by the number i got before but it ...
100. ### Physics

Please help due in less than 2 hours!! A person whose mass is m = 86.0 kg steps on a mechanical bathroom scale placed on an inclined plane that makes the angle α = 21.3° with the horizontal. What is the reading on the scale? i've tried m*g*sin(21.3) and it still says I'm...