130,813 results, page 59

1. ### Physics

A 14.1 μF capacitor is charged to a potential of 45.0 V and then discharged through an 80.0 Ω resistor. (a) How long after discharge begins does it take for the capacitor to lose 90.0% of the following? (i) its initial charge in seconds (ii) its initial energy in ...

Divide the following radical and simplify the answer. ((-3-2√48))/((14√50-8)) A.(24+210√2+64√3+560√6)/(-9736) B.(12+105√2+32√3+280√6)/(-4868) C.(12+105√2+32√3+280√6)/4868 D. (24+210√2+64√3+560√...
3. ### physics

A solid sphere of uniform density starts from rest and rolls without slipping down an inclined plane with angle θ = 30o. The sphere has mass M = 8 kg and radius R = 0.19 m . The coefficient of static friction between the sphere and the plane is μ = 0.64. What is the ...
4. ### history

I need to interview someone who was born before 1970 and live in the United States during the eighties. Here are some questions. Who were some of the national heroes of the 80s? What do you remember about the Iran-Contra Affair? Please comment on the fashion, styles, fads of ...
5. ### physics

On a perfect fall day, you are hovering at low altitude in a hot-air balloon, accelerated neither upward nor downward. The total weight of the balloon, including its load and the hot air in it, is 24000 N. Find the weight of the displaced air. I got the weight=2.4×10^4 N but ...
6. ### physics

On a perfect fall day, you are hovering at low altitude in a hot-air balloon, accelerated neither upward nor downward. The total weight of the balloon, including its load and the hot air in it, is 24000 N. Find the weight of the displaced air. I got the weight=2.4×10^4 N but ...
7. ### physics

1) A golf ball is hit from a position that is 4m higher than h ehorizintal area where the ball lands. The intiial velocity of he ballis 30ms-1 at a angle of 0 above the horizintal a)show that the maximum height of the ball above the landing area is approximately 38.4m. b)show ...
8. ### Physics

Could you please check my answers and units. Thanxs! 1. An automobile starts from rest and accelerates at 3m/s2 for 4 seconds. How fast is it going after acceleration? -I got 12 m/s 3. At time = 0 an automobile already traveling at 30 km/hr. accelerates at 3m/s2 for 2 seconds...
9. ### Physics

a person pushes on a hockey puck with their stick at an angle so the vertical force is 22N down and the horizontal force is 45N forward. Assume the ice is frictionless. What is the actual force the hockey player transmits to the puck? what is the work done by the person ...
10. ### physics

two balls collide in a head on elastic collision and rebound in opposite directions. One ball has velocity 1.2 before the collision and -2.3 after. the other ball has a mass of 1.1 kg and a velocity of -4.2 before the collision. What is the mass of the first ball? What is the ...
11. ### Physics

100g of radioactive element X are placed in a sealed box. The half-life of this isotope of X is 2 days. After 4 days have passed, what is the mass of element X in the box? b) If the box is completely evacuated (perfect vacuum), then N atoms of X are added. After 4 days have ...
12. ### Chemistry

Suppose that 2.3 L of gas at 35°C and 1.0 atm is expanded to 4.5 L at 42°C. What will the final pressure of the gas be? (Ti in Kelvins=308.15; Tf(K)=315.15) Can someone please show me how to plug the values into the Combined Gas Law formula to calculate for Pf? Please don't ...

14. ### Physics

Someone please help me with this. The speed of ocean waves depends on their wavelength Î» (in meters) and the gravitational field strength g (in m/sË†2) in this way: V=KÎ»Ë†p GË†q Where K is a dimentionless constant. Find the value of the exponents p and q. This ...
15. ### PHYSICS LEC

please help...i need this immediately.. rolling friction. two bicycles are set rolling with the same initial speed of 3.50m/s on a long, straight road, and the distance each travels before its speed is reduced by half is measured. One tire is inflated to a pressure of 40psi ...
16. ### Physics

A woman driving her car approaches an intersection and begins to accelerate just as the traffic light turns green. Her velocity is the function of time described by the equation: v(t)=2t^2-8t+10 (A) Use calculus to find her instantaneous acceleration at t=8.0seconds (B) Use ...

An accelerometer in a control system consists of a 2.42 g object sliding on a horizontal rail. A low-mass spring is connected between the object and a flange at one end of the rail. Grease on the rail makes static friction negligible, but rapidly damps out vibrations of the ...

A race car is one lap behind the lead race car when the lead car has 57 laps to go in a race. If the speed of the lead car is 66.2 m/s, what must be the average speed of the second car to catch the lead car just before the end of the race (i.e., right at the ﬁnish line...
19. ### Physics quick help please

6. If 4.0 × 1018 J of work done on a point charge changes its electric potential difference by 25.0 V, then what is the magnitude of the charge? (Points : 1) 1.6 × 101^9 C 4.0 × 101^9 C 1.6 × 101^8 C 4.0 × 101^8 C 7. Two parallel plates have an electric field strength ...
20. ### physics

Hi, could anyone help me please, Thank. Gas in a container is at a pressure of 1.3 atm and a volume of 1.0 m3. (a) What is the work done on the gas if it expands at constant pressure to twice its initial volume? (b) What is the work done on the gas if it is compressed at ...
21. ### physics

Hi!could anyone help me please, Thank. Gas in a container is at a pressure of 1.3 atm and a volume of 1.0 m3. (a) What is the work done on the gas if it expands at constant pressure to twice its initial volume? (b) What is the work done on the gas if it is compressed at ...
22. ### PHYSICS!!!

A 0.30-kg softball has a velocity of 12 m/s at an angle of 30° below the horizontal just before making contact with the bat. What is the magnitude of the change in momentum of the ball while it is in contact with the bat if the ball leaves the bat with a velocity of 17 m/s, ...

suppose a cart of mass m = 969 g is initial moving at speed v0 = 5.17 m/s. It strikes a spring attached to a fixed wall, comes to a stop, and bounces back at speed vf = 4.48 m/s. Assume the track is frictionless. a) Find the magnitude of the impulse exerted by the spring on ...
24. ### physics conceptual

The tires of a car support the weight of a stationary car. If one tire has a slow leak, the air pressure within the tire will _______ with time, the surface area between the tire and the road will ________ with time, and the net force the tire exerts on the road will ...
25. ### Math

How do I simplify this: (The ^ symbol means 3) -3(12)-{5(-4)-2^ I tried it,and got-8,however when I rechecked my work I got -64. Please help! Please help! where is the other } in the equation? And ^ means to the power so -2^3 would be minus 2 to the 3rd power. Please rewrite ...
26. ### Spanish

Can someone please proofread my Spanish? Thank you. it will not let me post my HW because it says that I have posted a link but I haven't. Thank you for using the Jiskha Homework Help Forum. We'd be glad to proofread it if you can post it! Please try again. You can not copy ...
27. ### Terry High School

5,3x-7=2x+1 Please never put personal identifying data in your post, like the address, or full name, or the name of your high school. The world is a dangerous place. Please discuss this with your mom. I can tell what you mean by 5,3x What are you trying to do, solve for x?
28. ### info again.

I need the story of a cuban-american that came by boat. I have been searching, I cannot find anything. Please let me know. I am so frustrated. Please help me. If I can find a more detailed story of the korean-american rather than the one that you gave me that will be very ...
29. ### To "lil sharon"

I've removed your post with your complex assignment that expects you to do some thinking and supply answers. Please repost when you tell us what you think the answers are for each question. Please also put the SCHOOL SUBJECT in the appropriate box. "College" is not a school ...
30. ### Geography

Please can you tell me whether the north italian plain or the south of italy would have a) hydro-electric power available b) few natural resources. I cannot find the answers to them. One answer goes on north and one on south. Please help.
31. ### math

I need to simplify the following rational exponent: (64n^9)^2/3 I've done the following but don't think this is right: = 3|64n^18 = 4n^2.62 I don't know how to type in the root symbol so I used | to mean root. Can someone please verify this and if incorrect please explain ...
32. ### English

Can you please check these two sentences, please? Thank you 1) Nature ceased to be considered as a philosophical entity (concept?). It came to be felt as a real living being (real and living being) and to be described as it actually was. 2) The Romantics were concerned about ...

You are given two different circles. The diameter of the first circle is the radius of the second circle. What is the ratio of the area of the larger circle to the area of the smaller circle. Your answer should be in the form of a simplified fraction. I have no idea where to ...

A sample consisting of various gases contains 2.6 10-6 mole fraction of radon. This gas at a total pressure of 37 atm is shaken with water at 30°C. Calculate the molar concentration of radon in the water. Can somepne please provide a step by step instruction?

A coffee cup calorimeter contains 100ml of .200M H2SO4 at 22.3 degrees Celsius. When 2.16g Mg is added, the temperature rises to 36.3 degrees Celsius. What is the heat of the reaction per mole Mg? Please help and show steps. Much appreciated :)
36. ### U.S. Government

Which part of the Constitution was at issue in the nullification crisis? the supremacy clause the elastic clause the necessary an proper clause the interstate commerce clause I really don't know which one because I don't really understand the question but I'm thinking that its...
37. ### Physics

Some stoves use the heat produced by current flowing through a conductor. If the heating element (conductor) has a resistance of 30 ohms, how long will the burner have to work to heat 500 g of 30°C water up to its boiling point? The specific heat of water is 4.19 x 103 J/kg...
38. ### Physics

Please solve and answer. Need done ASAP. A speeder passes a parked police car at 35.0 m/s. The police car starts from rest with a uniform acceleration of 2.39 m/s2. (a) How much time passes before the speeder is overtaken by the police car? __ s (b) How far does the speeder ...

charlie can not remember how much he financed to buy his car.. he does remember that his monthly payment is \$200 and his add on interest rate was 12% and he made a total of 18 payments. find the amount of his loan to the nearest penny. I keep getting over a 4000 and the actual...
40. ### chemistry

From the list of compounds below identify each of their molecules: 1. Propanone C3H60 Mr=58 2. Chromium trioxide Cr2O3 Mr= 152 3.Rubidium Carbonate Rb2CO3 Mr=231 4.Neon Ne: Mr= 20.2 5. Nitrophenol C6H5NO3 Mr= 139 6. Dinitrogentetraoxide N2O4 Mr=92 Please help I am really ...
41. ### Physics

Hi, I have a question for physics An object with mass m = 20 kg is released from a height h = 60 m above the ground. After 2 seconds, the object's quantity of energy Thanks for your help mvh Oddbjørn
42. ### physics

A physics book of unknown mass is dropped 5.00 m. What speed does the book have just before it hits the ground? Assume that air resistance is negligible
43. ### physics

when a 100 m runner reached the finish line , the runner stopped suddenly and fell on the ground . explain the situation using the appropriate physics concep
44. ### Physics

A 150N block rests on a table. The suspended mass has a weight of 73N. a) What is the magnitude of the minimum force of static friction required to hold both blocks at rest? Answer in units of N b)What minimum coeﬃcient of static friction is required to ensure that both...
45. ### Physics

A 150N block rests on a table. The suspended mass has a weight of 73N. a) What is the magnitude of the minimum force of static friction required to hold both blocks at rest? Answer in units of N b)What minimum coeﬃcient of static friction is required to ensure that both...

Sam is sitting in her fishing boat watching a trout swim below the surface. She guesses the apparent depth of the trout at 2.0m. She estimates that her eyes are about 1.0 m above the water's surface, and that the angle at which she's observing the trout is 45 degrees. a) draw ...

A long thin rod lies along the x-axis from the origin to x=L, with L= 0.890 m. The mass per unit length, λ (in kg/m) varies according to the equation λ = λ0 (1+1.410x2). The value of λ0 is 0.700 kg/m and x is in meters. 1. Calculate the total mass of the ...
48. ### Physics

A train blows its horn as it approaches a crossing. A.) if the train engineer observes a frequency of 125Hz and a stationary observer at the crossing observes a frequency of 132Hz, what is the speed of the train? (The speed of sound is 330m/sec on this day). B.) what frequency...
49. ### Physics

A spacecraft is on a journey to the moon. At what point, as measured from the center of the earth, does the gravitational force exerted on the spacecraft by the earth balance that exerted by the moon? This point lies on a line between the centers of the earth and the moon. The...

A planet has two satellite moons. Moon X has an orbital period of 2.13 days. Moon Y has an orbital period of about 3.53 days. Both moons have nearly circular orbits. Use Kepler's third law to find the distance of each satellite from the planet's center. The planet's mass is 2....
51. ### Physics

Bob and Ray push on a door from opposite sides. They both push perpendicular to the door. Bob pushes 0.63 m from the door hinge with a force of 89 N. Ray pushes 0.57 m from the door hinge with a force of 98 N, in a manner that tends to turn the door in a clockwise direction. ...
52. ### Physics and the movies

Would A.I. and Pearl Harbour be good movies to analyze for physics mistakes?
53. ### physics

Name of physics book for 11 and 12.to catch engineering exam and other competetive exam

A spacecraft is on a journey to the moon. At what point, as measured from the center of the earth, does the gravitational force exerted on the spacecraft by the earth balance that exerted by the moon? This point lies on a line between the centers of the earth and the moon. The...
55. ### Physics 12

"A pendulum consisting of an object of mass 1.3kg suspended from a string of length 1.9m is pulled aside so that the string makes an angle of 28 degrees with the vertical. At the instant the pendulum is released, what is the magnitude of the unbalanced force on the object?" I ...
56. ### physics

In an electrically heated home, the temperature of the ground in contact with a concrete basement wall is 13.0 oC. The temperature at the inside surface of the wall is 21.1 oC. The wall is 0.19 m thick and has an area of 8.3 m2. Assume that one kilowatt hour of electrical ...
57. ### Quantum Physics

Suppose you are given an endless supply of qubits in the state 12√|00⟩+eiϕ2√|10⟩. To estimate the phase angle ϕ, you run Fourier sampling (i.e. Hadamard on each qubit followed by a standard basis measurement) on this state repeatedly. After ...
58. ### Physics Word Problems

Could you please explain to me these problems, I don't understand them. Do 100 J of work in 50 s and your power output is? - I got 2, but not sure of the units. A bow is drawn so that it has 40 J of potential energy. When fired, the arrow will ideally have a kinetic energy of...
59. ### AP physics

Suppose a Chinook salmon needs to jump a waterfall that is 1.50 m high. If the fish starts from a distance 1.00 m from the base of the ledge over which the waterfall flows, find the x- and y-components of the initial velocity the salmon would need to just reach the ledge at ...

A generating station is producing 2.00 106 W of power that is to be sent to a small town located 7.0 km away. Each of the two wires that comprise the transmission line has a resistance per kilometer of length of 5.00 10-2 /km. (a) Find the power lost in heating the wires if ...

A coin rests 18.0 cm from the center of a turntable. The coefficient of static friction between the coin and turntable surface is 0.420. The turntable starts from rest at t = 0 and rotates with a constant angular acceleration of 0.650 rad/s2. (a) After 3.00 s, what is the ...

A coin rests 18.0 cm from the center of a turntable. The coefficient of static friction between the coin and turntable surface is 0.420. The turntable starts from rest at t = 0 and rotates with a constant angular acceleration of 0.650 rad/s2. (a) After 3.00 s, what is the ...

0.0100kg particles have been glued to a rod of Length L=6.00cm and negligible mass and can rotate around a perpendicular axis through point O at one end. How much work is required to change the rotational rate (a) from 0-20.0 rad/s, (b) from 20.0 rad/s to 40.0 rad/s, and (c) ...

A large grinding wheel in the shape of a solid cylinder of radius 0.450m is free to rotate on a frictionless, vertical axle. A constant tangential force of 180 N applied to its edge causes the wheel to have an angular acceleration of 0.870 rad/s2. (a) What is the moment of ...

(imageshack)(.)us(/)photo (/) my-images (/)42(/)2vja. jpg(/) Open that link please , just delete the parentheses please please help me with my assignments I beg you cooperate with me huhu 1. in the figure , the areas of traingle cef, triangle abe, triangle adf are 3,4, and 5 ...
66. ### Math

Simplify: 5x{24-19)x[25+23)divided by 12-(9-7)} Please help! Subject is algebra. sorry- please help! Am I working the problem correctly? IS THE ANSWER 50? 5x{24-19)x(25+23)divided by (12-(9-7)) = (5x5x48)/(12-2) = (25 x 48)/10 = ? No, the answer is not 50. As best as I can ...

Which answer shows data with a range of 49? A. 45,69,92,59 B. 95,59,52,89 C.99,66,51,52 D.55,99,78,50 if you select one of the answer .How do you solve the problem.? i was wonder how ?please explain your answer please!! so the next problem i try to solve by myself.for me thank...
68. ### Official meaning

What is an official? A person who holds an office. Could you please explain more to me? What is a governor? An appointed or elected official who governs a state, colony, or province for a specific term. Could you please explain more.
69. ### math30

A sequence has a first term of 24 and every other term is one half of the previous term. Find a recursive formula that defines this sequence. The answer of this question is: an=an-1*1/2 Somebody can help me and let me know why is 1/2 on the formula? please please!!!
70. ### SAT Math

I don't remember what problem I struggled to understand... But it was something like this... There are 3000 numbers so how many of them are odd.. Something like that.. Please give me a problem like that and please teach me!!!! I hope you know what I am talking about!!

Assuming that limits as x → ∞ have the properties for limits as x → c, use algebraic manipulations to evaluate lim x → ∞ for the function. a. f(x) = x − 2/2 + 6x^2 b. f(x) = x^2 + 6/x + 7 Please help! I do not know how to start with this ...
72. ### Language Arts

I need to practice writing summaries and small essay for my 9 week exam and I am not very good at writing summaries or essays. Can you please help me or provide me with a website that I am able to do practice summaries on. Please help.
73. ### English

1. Please call at 123-4567. 2. Please call 123-4567. 3. Please call me at 123-4567. (Which expressions are right?)
74. ### math

Please help. Please. using the numbers 24 12 2 7...in any addition subtraction division or multiplication combination, i have to come up with the sum of 24. Help. I have tried every combination i can think of the closest i have come is 22 or 26

In a murder investigation, the temperature of the corpse was 32.5 C at 1:30pm and 30.3 C an hour later. Normal body temperature is 37.0 C and the temperature of the surrounding was 20.0 C. When did the murder take place? PLEASE SHOW STEP BY STEP

In a two-digit number, the tens’ digit is 1 less than the units’ digit. If the digits are interchanged, the sum of the number obtained and the original number is 143. Find the number.
77. ### physics

i'm having a lot of trouble with these and can't seem to figure them out no matter how many times i replace variables in my equations and write down what i know and need and i don't know what to do about it anymore. The speed of a boat undergoing constant acceleration ...

Check answers please! 1. Many indigenous people in Guatemala live in the mountains because it is the only land available to them the soil is very good for farming*** they don't speak Spanish mountain villages are easy to defend against attacks 2. All of the following are ...
79. ### Physics

An object is placed in front of a converging lens in such a position that the lens (f = 13.2 cm) produces a real image located 23.5 cm from the lens. Then, with the object remaining in place, the lens is replaced with another converging lens (f = 18.8 cm). A new, real image is...
80. ### AP Physics

A Physics book has a height of 26 cm, a width of 22 cm, and a thickness of 4 cm. Find the pressure that the Physics book exerts on a desktop when the book lies face up and when the book is balanced on its spine. I know that P=F/A, I am just not sure which dimensions of the ...
81. ### English

What does it mean to vary the sentence pattern within a written work? (Please give some answer...Not just a web link...And if you give a link please give info on where answer might be located.)
82. ### Algebra

Please my mentors, I urgently needs your support please. A number of two digits is such that the tens digit is 8 less than seven times the unit digit. When the digits are reversed, the number is decreased by 9. What is the number?
83. ### math

please help thanks :) what does PITI mean example Find the monthly PITI payment of this loan ? Sue recently purchased a home, taking out a mortage of \$235,000 at 8 3/4% for 25 years annual property taxes are \$6,345 and annual hazard insurance premium is \$1,479 please explian ...

Pete's Plymouth travels 200 miles at a certain speed. If the car had gone 10 mph faster, the trip would have taken 1 hour less. Find Pete's speed. I am very confused about how to solve this problem! Please explain well. Thank you so much!!! :-)
85. ### SS7R HELP!

I have a worksheet for which is due tomorrow and my teacher is grading it. I'm having trouble with 3 questions (it have 7 questions) please help me. 1. Why did the western farmers oppose Spanish and French control of New Orleans? 2. Why was Toussaint L' Ouverture important to ...

A pizza box top with a square base is to be made from a rectangular sheet of cardboard by cutting six 1-inch squares from the corners and the middle sections and folding up the sides. If the area of the base is to 144 in^2, what piece of cardboard should be used. Please ...
87. ### Trigonometry

PLEASE HELP!! I really don't understand this...I just started learning about trigonometry and SOH CAH TOA and I think this probably has to do with that but I don't know how to apply it... Please explain this to me!!!! I need to know how to do it and not just the answer. ...
88. ### Physics

I've been working on this problem for close to an hour now and keep getting very wrong numbers... The two objects with different mass (m1 = 5.0 kg and m2 = 3.0 kg) in the Atwood's machine shown in the figure are released from rest, with one object at a height of 0.91 m above ...

Mary has a solution that is 60% alcohol and another that is 20% alcohol. How much of each should she use to make 100 milliliters of a solution that is 52% alcohol. I totally forget how to do this kind of problem. Please help if you can! Thank you so much! :)
90. ### Math

A bag contains 6 red marbles, 3 white marbles, and 7 blue marbles. You pick a marble without looking. Find the probability of drawing a white marble. A. 3/7 B. 7/16 C. 3/16 D. 13/16 Please help please and thank you
91. ### Physics

I studied the equation of time recently and understand the Earths keplerian orbit is responsible for it. I understand the keplerian orbit described the Earths elliptical path and it was this alone that created the equation of time. I have just read that the Earth does not ...
92. ### Physics

A child is twirling a 0.0116 kg ball on a string in a horizontal circle whose radius is 0.102 m. The ball travels once around the circle in 0.560 s. (a) Determine the centripetal force acting on the ball. N (b) If the speed is doubled, does the centripetal force double? yes no...
93. ### Physics

A child is twirling a 0.0116 kg ball on a string in a horizontal circle whose radius is 0.102 m. The ball travels once around the circle in 0.560 s. (a) Determine the centripetal force acting on the ball. N (b) If the speed is doubled, does the centripetal force double? yes no...
94. ### physics Classical Mechanics

Hi, Greco. I am using the following formula to solve Ballistic Missile: sqrt(5*G*m_1/4*r_1). Given the following: m_1=5*10^24kg; r_1=6000;alpha=30 degrees;r_2=(5/2)r_1; G= 6.674*10^-11kg/m^3s^-2. I thought I did it correctly using the proper formula. My answer was incorrect. I...
95. ### physics

A 0.700-kg ball is on the end of a rope that is 2.20 m in length. The ball and rope are attached to a pole and the entire apparatus, including the pole, rotates about the pole's symmetry axis. The rope makes an angle of 70.0° with respect to the vertical as shown. What is the...
96. ### physics

A 0.700-kg ball is on the end of a rope that is 2.20 m in length. The ball and rope are attached to a pole and the entire apparatus, including the pole, rotates about the pole's symmetry axis. The rope makes an angle of 70.0° with respect to the vertical as shown. What is the...
97. ### college physics

If a girl drops a coin into a wishing well. After exactly 5 seconds she hears it splash into the water. How fast was the coin going after 1 second? After 2 seconds? How fast was the coin going when it hit the water? How far down is the water? Could you please help with the ...
98. ### physics help 2 please!

The air inside a hot air balloon has an average temperature of 84.3°C. The outside air has a temperature of 15.3°C. What is the ratio of the density of air in the balloon to the density of air in the surrounding atmosphere? inside / outside = ??
99. ### Physics

A block of mass 50 kg is pulled on a frictionless floor by F=210N directed to 30angle horizontally, If the block moves 3m, find work done? a. 115 √2J b. 315 √3J Answer is B 315 √3J , my question is how to solve it in this way i mean, i solved it like this, w=...