130,975 results, page 23

1. ### physics 30

an object is thrown from 1.5m above the ground with a velocity of 15m/s and at an angle of 25deg with the ground. using vectors and motion equations, determine how long the object will remain in the air before returning to the ground. ARGHHHHHH help please..
2. ### Physics

Could someone please check another one of my answer for me? Thank you! A commuter backs her car out of her garage with an acceleration of 1.40 m/s2. (a) How long does it take her to reach a speed of 2.00 m/s? (b) If she then brakes to a stop in 0.800 s, what is her ...

A speedboat starts from rest and accelerates at +1.90m/s^2 for 7.00 s. At the end of this time, the boat continues for an additional 6.00 s with an acceleration of +0.529m/s^2. Following this, the boat accelerates at -1.47m/s^2 for 8.00 s. **What is the total displacement of ...
4. ### physics

During lab students are asked to set up the Atwood's device shown in the diagram below. Mass 1 = 4.50 kg and mass 2 = 2.10 kg. If the distance to the floor, S = 1.20 meters, how much time is needed for mass 1 to reach the floor? please explain how to do this; i don't know how
5. ### Geometry

Please answer at least one . PLEASE 1. Triangle XYZ has a right angle at Y. V,W are on XZ such that XV=XY. WZ=YZ, find ANGLE VYW . 2. STUVWXYZ is a regular octagon. Find SW/ TZ. 3. The interior angles of a convex polygon form an arithmetic progression with a common difference ...
6. ### SOCIAL STUDIES

the outline achievement of Pope leo x I got: Lorenzo de Medici's son who published a bull disapproving of many of Luther's teachings & threatning the monk with excommunication or removal from church. This pope officially excommunicated Luther & put him on trial in city of ...
7. ### physics

A crystalline solid consists of atoms stacked up in a repeating lattice structure. The atoms of a crystal reside at the corners of cubes of side L = 0.200 nm. One piece of evidence for the regular arrangement of atoms comes from the flat surfaces along which a crystal ...
8. ### Home Economics/Science

Hi i just needed a little help with my Home Eco homework,could u help me please. here are the questions: what is the social,economical,ittellectual,cultural,protective,security functions of a family. please tell in paragraphs for each section. thanks!!! Please post your ...
9. ### Physics

A block weighing 70.7 N rests on a plane inclined at 21.6° to the horizontal. The coefficient of the static and kinetic frictions are 0.23 and 0.12 respectively. What is the minimum magnitude of the force F, parallel to the plane, that will prevent the block from slipping? ...
10. ### Physics

A block weighing 70.7 N rests on a plane inclined at 21.6° to the horizontal. The coefficient of the static and kinetic frictions are 0.23 and 0.12 respectively. What is the minimum magnitude of the force F, parallel to the plane, that will prevent the block from slipping? ...
11. ### Physics

A block weighing 70.7 N rests on a plane inclined at 21.6° to the horizontal. The coefficient of the static and kinetic frictions are 0.23 and 0.12 respectively. What is the minimum magnitude of the force F, parallel to the plane, that will prevent the block from slipping? ...
12. ### physics

A horizontal disc rotating freely about a vertical axis makes 90 revolutions per minute reduces to 60,then find the moment of inertia of the disc? 1. mr2 2. 3/2mr2 3. 2mr2 4. 3mr2 (the last ‘2’in each option should be considered as square, please)
13. ### physics

how would i go about solving this problem? what formula shoud i use? can you please show me in steps how to do this, thanks a lot: The critical angle of refraction for calcite is 68.4degrees when it forms a boundary with water. Use this information to determine the speed of ...
14. ### As Physics

Please help me with this calculation __________________ <- A vibrating wire which is 4cm long Diameter= 0.0002m Frequency= 2500Hz density of carbon steel= 7700kg/m3 How do i find the tension of this wire? This is some of the equations which we should be using: v= √T...
15. ### physics HELP

A projectile is fired with an initial speed of 1000 m/s at an angle of 37 degrees above the horizontal. If air resistance is neglected, the horizontal component of the projectile's velocity after 20 s is approximately A) 600 m/s B) 800 m/s C) 640 m/s D) 40 m/s E) 160 m/s ...
16. ### Physics

A stuntman sitting on a tree limb wishes to drop vertically onto a horse galloping under the tree. The constant speed of the horse is 10.0 m/s, and the man is initially 2.75 m above the level of the saddle. Please Show work!! I am completely lost!

the floors in a typical house are separated by a vertical distance of approximately 8.0 ft. a teenager (1.0x 10^2 lb) climbs the stairs between floors at a steady speed. find the power necessary to accomplish this if the stairs are climbed in (a) 10.0 s and (b) 2.0 s. express ...
18. ### PHYSICS

A block of mass'm'is dropped over a horizontal surface with an initial velocity'v'.the coefficient of kinatic friction is'u'(mev),while the acceleration due to gravity'g'before coming to rest the block travels a distance??how i can find the distance?please help me to do so!
19. ### Physics

A 0.140-kg baseball traveling 39.0 m/s strikes the catcher's mitt, which, in bringing the ball to rest, recoils backward 13.0 cm. What was the average force applied by the ball on the glove? May someone please take me through this problem step by step? Very lost????
20. ### Physics

An elevator (cabin mass 600 kg) is designed for a maximum load of 2100 kg, and to reach a velocity of 3.1 m/s in 3 s. For this scenario, what is the tension the elevator rope has to withstand? This is what I've tried and is incorrect. 2100kg + 600 kg= 2700kg (m) (3.1/3)= 1....
21. ### Physics

A concave mirror is constructed so that a man at a distance of 19 cm from the mirror sees his image magnified 2.0 times. What is the radius of the curvature? OK so I have tried to work this out and can't seem to find the answer. Here is what I got. Please let me know if you ...
22. ### physics (Newton's Laws)

If an acrobat who weighs 800 N is clinging to a vertical pole using only his hands, neither moving up nor down, can we determine the coefficient of static friction between his hands and the pole? Explain your answer. Please, help. Thank you
23. ### Physics :(( help please TT

The space shuttle had a top orbital speed of 8000 m/s and orbited in a circular orbit approximately 320 km above the earth's surface. How long was one orbit in seconds? Details and assumptions The radius of the earth is 6370 km.
24. ### Math/Physics

A 500kV power line has a maximum permissible Voltage drop of 3% and is design to carry 1000 Amps. If the conductor has a 0.026 ohms/km resistance, what is the maximum distance the conductor can be run (to the nearest complete km)? Hint: P=IE, E=IR How do I solve this? Please ...
25. ### Physics - please check my answer

A man tosses a ball upward. It reaches its highest point after 25 seconds. Find its initial velocity. Alright, so I tried solving this. I used the equations (let v = initial velocity): h = v^2 / 2g , and h = (v*t) - (1/2)(g)(t^2) and I got 101.48 m/s. Is this correct?
26. ### Physics

A conical pendulum rotates at 100 rev/min. The cord is 150mm long and the mass of the bob is 1.35kg. Find (a)the amount by which the bob rises above its lowest position , (b)the periodic time , (c)the tension in the cord . ( PLEASE HELP ME FOR MY REPORT )
27. ### Physics

Three carts of masses 4kg, 10 kg, and 3 kg move on a frictionless horizontal surface with initial speeds of 5 m/s, 3 m/s, and 4 m/s. If the carts all stick together after the collisions, what will be the final velocity of the combined mass? Help ASAP please. Step by step to ...
28. ### Physics

A baseball traveling upward passes a window 29.0 m above the street with a vertical speed of 14.0 m/s. If the ball was thrown from street level, what is the maximum height that the baseball reaches? Im stumped, please tell me what equations to use as well as what each variable...
29. ### 7th grade math check

Ok I was wondering if you could check these 3 problems please. I am suppose to set these equations equal but I am not sure if did them right. I think I accidently solved these systems as substitutions. The answers are suppose to be in coordinate pairs. 1) x - y = 11 -3x + y...

Sorry to repost this, again, but I still don't understand. Newton’s Law of Gravity specifies the magnitude of the interaction force between two point masses, m1 and m2, separated by the distance r as F(r) = Gm1m2/r^2. The gravitational constant G can be determined by ...
31. ### Physics

A ball of mass 3kg is tied to a rope with a length of 1.3m. If the ball is spun at a rate of 300rpm's, find the tension on the rope, the centripetal force, and the centripetal acceleration. Please help, I have a test on it tomorrow.
32. ### physics

please check Which of the following is NOT a characteristic of electrical potential energy? a. it is a form of mechanical energy b. it results from a single charge c. it results from the interaction between charges d. it si associated with a charge in an electric field A
33. ### Physics

A satellite has an orbit with pedigree 175 km and apogee 181,200 km. What is the period of the orbit? >>I'm not sure what the associated equation is. I tried the problem using the average radius in the period equation but it didn't work. Please help!
34. ### Physics

Calculate the force of gravity on a spacecraft 19200 km (3 earth radii) above the Earth's surface if its mass is 1600 kg. I've done all the work but I can't seem to get the right answer, please show work and answer.

A mass of 30 kg lies on a horizontal surface with a coefficient of static friction of 0.72 and a coefficient of kinetic friction of 0.31. If a force of 25.1 Newtons is applied parallel to the surface (+x direction if you prefer), what is the magnitude of the acceleration of ...
36. ### Physics

Describe 4 everyday situations where mechanical energy is approximately conserved because work done by the non-conservative forces is ignorable. Please mention which non-conservative force is doing negligible work in each case you cite. Thank you!
37. ### Physics

Please show steps and thank you! An astronaut of mass 70 kg carries an empty oxygen tank of mass 14 kg. He throws the tank away from himself with a speed of 3 m/s. With what velocity does the astronaut start to move through space?

A half-open pipe is constructed to produce a fundamental frequency of 230 Hz when the air temperature is 17 °C. It is used in an overheated building when the temperature is 39 °C. Neglecting thermal expansion in the pipe, what frequency will be heard?
39. ### Physics :(( help please TT

Small raindrops are actually perfectly spherical. The pressure difference between the inside and outside of a spherical raindrop of volume 4.2×10^−9 m^3 is 280 Pa. What is the surface tension in N/m of the water on the outside of the raindrop?
40. ### physics

You launch a model rocket up into the sky. Right after launch the rocket is accelerating upwards at 10 m/s^2. What is the magnitude of the net force in Newtons on the rocket if the rocket has a mass of 0.1 kg? Please give your answer with solution .
41. ### physics

As a train moves away from you, the frequency of its whistle is determined to be 475Hz. If the actual frequency was 500 Hz and the speed of sound in air is 350m/s, what is the Train's speed? answer is 18.4m/s please show and explain steps
42. ### Physics

Suppose that the amount of heat removed when 2.9 kg of water freezes at 0.0 oC were removed from ethyl alcohol at its freezing/melting point of -114.4 oC. How many kilograms of ethyl alcohol would freeze? I don't know where to start with this question! Please help.
43. ### physics

When swimming across a river you swim to the east at 1.0 mph while the river flows southward at 2.4 mph. Your velocity is a superposition of these two velocities. What is your speed (i.e. the magnitude of your velocity)? i have no idea how to do this please help
44. ### PHYSICS Electricity

A carbon atom's nucleus and its electrons become separated by 20nm . How much work does it take to separate them in J?I found the magnitude of the force the nucleus feels from the electrons,2.07*10^-11 N but the work? Could ex[lain me please?
45. ### physics

A boat moving at 13 mi/hr is crossing a river in which the current flowing at 6 mi/hr.ln what direction should the boat head if it is to reach a point on other side of the river directly opposite its starting point. Please help me I really don't know what to do..
46. ### Physics

a lawnmower with a mass of 12 kg is being pushed by a force of 150n horizontally and 40 n down. if the kinetic coefficient of friction between the grass is 0.9, find the force of friction on the lawnmower. Please explain this as well, I am getting an answer but I don't know.
47. ### Physics repost please clarify

A converging lens has a focal length of 0.060 m. An object is located 0.020 m to the left of this lens. A second converging lens has the same focal length as the first one and is located 0.100 m to the right of it. Relative to the second lens, where is the final image located...
48. ### physics help

a particle moves uniformly around the circumference of a circle whose radius is 8 cm with a period of pi/20 s. the angular velocity w of the particle is a. 2.5 rad/s b. 3.2 X 10^2 rad/s c. 40 rad/s d. 7.9 rad/s e. 96 rad/s please explain thanks!
49. ### Please HELP!!!!! I need to finish this by 12:30!!!

PLease Help!!My teacher is coming to pick this up at 12:30!!! Then don't waste your time pleading. Are you cheating on a test or something?
50. ### HUM 130

Please help me! I ned info. on this ? please I need to explain the desire for liberation from earthly existnce in Hinduism?
51. ### Math

Hello! Please help me out here. How do you find the circumference of something when you of 13in as your radius? Please answer this question.
52. ### calculus

from the equation: x^4 - i = 0 x^4 = i how do you get: The solutions are the fourth roots of i = cos(pi/2) + isin(pi/2) I don't understand how you get pi/2? please full and detailed explanation please.
53. ### science need info please

Where can I find some informations on three different types of ocean water Please ,
54. ### Algebra I

Could someone please help with these problems? 4x squared-5x + 3 if is a.3 b. 0.3 Please show me the work invovled on getting the answer, my teacher requests it. Thank you.
55. ### help please????

please can u give me some advices and sites or ANYTHING that can help me speak english very good and so fast. thank you alot.
56. ### math

Please help me. Thank you! I need help freshing my memory. How do you calculate the slope of a horizontal and a verticle line? I remember how to do a diagonal but that's it. Please and thank you.
57. ### Precalculus(URGENT)

determoine whether the equation defines y as a function of x y= the square root of(-3x-6) please please show work
58. ### Chemistry

How do the qualities of acids and bases help us in the natural world? Please help-I posted this yesterday and I really don't get it-can someone direct me,please? Thank you
59. ### math

I have 2 problems that I need solved. Can someone please help me? t+36t=0 second problem T^2-7t+12=0 Can you show me the steps please?
60. ### Literature

Please summerize and help me to understand M.H.Abrams-Structure and Style in the Greater Romantic Lyric? mail me please,thank you for your concern.
61. ### Algebra one help please?

Find the missing coeffectient in the equation of the line. -4x+by=10 that passes through (2,3) Could someone explain please.. Thanks.
62. ### Biology . Ahh , help me with this question please

summarize how unicellular organisms may have given rise to the first animals ? Please , & thank you(:
63. ### science

determine the weight of an object if its mass is 68kg and the pull of gravity is 9.8 m/s^2. someone please help me an show the work please
64. ### Algebra

Please help-What is the equation of the ellipse with foci (0,6), (0,-6) and co-vertices (2,0),(-2,0) Please explain the steps because I have 5 to do for homework-Thank you-I'm really stuck on this
65. ### statistics

Using the data set below please calculate the 2;8;6;9;5 Range What would be the percentile rank of the number 6? Help please!
66. ### statistics

population with a mean of 53.1 and standard deviation of 4.43 Calculate z score for xbar 49.8 from a sample of size 11 Someone please please help me!
67. ### Languagge

How do i describe the growth of the Spanish population in New mexico? From about 1650 to 1700. please help!! Thank you!!

I don't understand anything about writing and graphing exponential decay functions../: Explain please, with an example.
70. ### 8th grade math

y=1/4x-1 1/2y=x-2 2x+3y=3 3y=5-2x 4x-y=3 4x=y=1 I don't understand this can someone please help me! This is Systems of Equations please work out the problem and explain it how to do it.
71. ### Chemistry Help Please

i do not understand how to solve this problem, please help 10.0mL 0.5M sulfuric acid can neutralize what volume of 0.5M ammonium hydroxide?
72. ### Math

Evaluate the integral from 0 to 4 of (x+1)/(16+x^2) dx the answers are log(sqrt2) + pi/16 Could you please take me through how to get to that answer please, thank you very much!
73. ### medical transcription

Please help to perfect my grammar, lot of confusion and trouble, please help me. Now usage of "complains of" and "complaints of"
74. ### civics

Q: which industries in the pacific region most affect the nation. can someone please take their time and please help me with this question? Thank you!!!

Homework - Draw a cartoon that represent a solid, liquid, and a gas. I'm struggling with this assignment, please help me!!!!
76. ### college algebra--need help please!!

find the domain of the composite function fog. f(x)= 2/x-3; g(x)= 7/x please show all work.
77. ### calculus

find the bound on the real zeros of the polynomial function f(x)=x^4+x^3-4x-6 cna you please show me how you got the answer please
78. ### Analytic geometry

What is the distance of the line x+6y-7=0 from the origin? Please help, is my answer -7sqrt37/37 correct? If not, please help me whats the right solution
79. ### mathURGENT!!!!!!

the lines satisfying the equations x+2y=3 and 3y+ax=2 are perpendicular to each other. find the value of 'a'. please answer and explain how you got, please!!
80. ### english

what are topic sentences and transitions? please tell me and let me know and if you can help me i thank you very much bye oh and please give me the anwsers too so i can get it for the test
81. ### Science Help - Please

Can you please tell me if this is a balanced equation for Zinc and acetic acid... Zn(s) + 2CH3COOH(aq)-->Zn(aq)(CH3COO)2 + H2(g) I would appreciate any help

Explain the effects of World War II, on both the United States and on Georgia. (5 points) please help

How does increasing the size of an object affect it's volume to surface area ratio? I don't understand please explain it?
84. ### Vocabulary

Criticism A. Analysis B. Summary C. Critique D. Argument A is wrong. Is it C? Please help me Ms.Sue cause your always correct. Am begging for help Please.
85. ### english help please!!

Identify three search combinations you could use to find information about technology on the internet? Please help me....
86. ### math

Which ratios form a proportion? (A)3/15,12/55 (B)8/24,12/35 (C)5/18,25/90*^* (D)4/11,16/25 If I'm wrong please help me and correct me, don't yell at me for not knowing the right answer. please help asap
87. ### Math

Can someone please help me find my maximum height. I have my distance which is 80ft and my angle of elevation is 70ft. PLEASE HELP ME!!

What would be a person target heart rate be if they are 14 years old? I know it starts like 220-14=206 but then what... Please help
89. ### s.s

where were most native americans in north america located when europeans arrived? there are no choices so just help me with this someone please help please!!!!!
90. ### chemistry

How many g of NaOH is needed to make 300.0 mL of a 20 % (w/v) solution? please please show all work I'm very lost
91. ### Math

A cookie jar contains 3 chocolate-chip, 2 peanut butter, 1 lemon, 1 almond, and 5 raisin cookies. a) In how many ways can you select some cookies, if you must include at least one chocolate-chip cookie. Please please please.. reply back asap.. i am totally confused with ...

please help!! what is 6 times the sum of 13 and a number? 6(13+ N)

*Please solve the rational expression. x^2/x-4 - 7/x-4=0
94. ### ms.sue please answer the trigonomitry question

Hi!! What is Night Eating Syndrome? Please Help!! Thank You!!
96. ### Algebra

Help please....Please Simplify (-3a^-5 b^6)^4 (a^7b^0)^3 any ideas? thanks in advance!