# Posts by andrea

Total # Posts: 856

**chemistry**

sir i didn't understand the first i made it more detailed for u though ty

**chemistry**

a carbon containing 3 atoms of carbon and 8 atoms of hydrdren combinend in reactionwith oxygen molecules the 2 end products of this equation are carbon dioxide co 2 an water what element should i look at first inn this oxygen hydrogen carbon or dioxide and wen finish balancing...

**chemistry**

my ques ok a coumpond containing 3atoms of carbon an 8 atoms ofhydrogen combined in reaction with oxy molecules the two end products of this equation are carbon dioxide co2 an water wat element should i look at first in balancing this question and wen i hav finished balancing ...

**Englis**

Name any fallacy in this essay One day in January 1995 a number of companies in San Diego, California, woke up to find that they had a "deficient work force." This new designation, which had literally come overnight, had nothing to do with the intelligence of the ...

**English**

A poem by Linda pasta can be found here: "w w w. theatlantic . c o m / doc/200708 / linda-pastan-ash" (withoutspaces) I was wondering if my analysis of this poem is correct. This poem is about death. When you're cremated you are transformed from a body into ashes...

**Mathematics**

Give the place value of 7 in 3,738,500.

**arithmetic**

Give the place value of 7 in 3,738,500.

**Physics**

If the distance between two slits is .05mm and the distance to the screen is 2.5m find the spacing between the first and second order bright fringees for yellow light of wavelenght 600nm. d=5x10^-5m L=2.5m wavelength= 6x10^-7m x=? x=wavelength*L/d =(6x10^-7)(2.5)/5x10^-5m =....

**Physics**

4th order dark fringe and 2nd order bright fring spaced 2.5cm apart appear on the screen placed 1 m behind the double slit. What is the spacing of the slits if the waveleght of incident light is 500nm? x=2.5cm=.025m L=1m wavelegth= 500nm = 5x10^-7m d=? x/L=wavelength/d d= (...

**Physics**

magnetic field lines near a wire perpendicular to this page carry current out of page a_ circles clockwise b_ circle counter-clockwise c_ radiate inward d_ radiate outward isn't it b) when you use the right hand rule

**Physics**

An optometrist has perscribed you 2D glasses. This means a) you are farsighted and the focal lenght of your glasses lens is +.5m b)you are nearsighted and the focal lenght of your glasses lens is +.5m c)you are farsighted and the focal lenght of your glasses lens is -.5m d)you...

**Physics**

Which of the following is NOT true? A permanet magnet: a) will always be magnitized b) can be demagnitized by heating c) can be demagnitized by hammering d) can be remagnitized by placing it in external magnetic field I eliminated c),and d) I think the correct answer is a) ...

**Physics**

Which one is a true statement? The magnetic field of the Earth: a)never changes b)continuously changes c) sometimes vanishes entirely d) is uniform Isn't it b) I know that a) and c) are wrong.

**Physics**

Three particles have identical masses and identical inital velocities. These particles are projected one at a time into a region in which there is a uniform magnetic field B perpendicular to their velocities. If two of the particles are deflected in opposite directions and the...

**Physics**

The incident ray comes at 30 degrees to normal at the air/glass boundary and is refracted at 18 degrees to normal. a) find index of refraction of glass b)find speed of light in glass c) under what conditions and for what angles will you have total internal reflection in this ...

**Physics**

What is the critical angles for water ice when surrounded by air? theda critial = arcsin(n2/n1) =arcsin(1/n1) What is the index of refraction of water ice? also is the above equation correct?

**Physics**

n=1.331 for red light in water and n=1.34 for blue light in water. If a ray of white light enters the water at 83 degrees what are the underwater angles of refraction for the blue and red components of white light? Also using Snell's law : (sin theda 1/ sin theda 2) = (n2/...

**Physics**

A ray of light stikes a flat 2 cm thick block of ice (n=1.5) at an angle of 45 degrees. Refracted ray travels through the glass and then is refracted back to air at the opposite side of the block. Find the angles of incident and refraction at each surface. Snell's law ...

**Physics**

A beam of light is incident on the surface of clear ice at 60 degrees with the normal. Find the angle between reflected and refracted ray. theda 1=60 n1= 1 (air) What would n2 be for clear ice? I know that index of refraction for water is 1.33. Would it also be 1.33? Snell'...

**Physics**

Find the speed of light in flint glass if the index of refraction is n=1.66. How much slower in percent of speed of light in a vacuum c does the light move in each of this medium? v=c/n v=3x10^8m/s/1.66 =1.8x10^8m/s For the percent of speed of light in a vacuum c. Would it be...

**Physics**

Is it possible to see a virtual image? a)no they don't exist b)yes the rays appear to emanate from a virtual image c)yes since almost everything we see is virtual because most things do not themselves give off light, but only reflect light coming from some other source d)...

**Physics**

an electric field is produced by a a)consant magnetic field b)changing magnetic field c)either a consant or changing magnetic field d)none of the above I choose b) because in a lab we once dealt with something similar to this question but I can't exactly remember whether ...

**C++ Programming**

how do you convert 2 for binary to decimal using c++ program

**Physics**

#1 If the inductance in the LC circuit is quadrupled the natural frequency of that circuit will a)increase to 4 times its original value b)increase to twice its original value c)decrease to 1/2 of its original value d)decrease to 1/4 of its original value Isn't the correct...

**Physics**

You have two identical resistors 50kohm each and a 1.5V battery. Which of the following statements are true a)the current drawn is bigger if the resistors are in series b) the current drawn is bigger if the resistors are in parallel c)the voltage across each resistor is bigger...

**Physics**

1)An electron moved from point A to point B along an equipotential surface. a)the eclectron performs work in moving from point A to point B b)Work is required to move the electron from point A to point B c)Work is both required and performed in moving the electron from point A...

**Physics**

The materials with the lowest resistance are called a) conductors b)superconductors c)semiconductors d) insulators I can't decide between a) or b) but if I had to choose one would the correct one be b)?

**Physics**

1)Several resistors are connected in parallel. If a battery provides constant voltage in this circuit the addition of another resistor in parallel a)increases current through each resistor b)decreases current through each resistor c)doesn't affect the current through any ...

**Physics**

An electron is placed near a neutron. Which statement best describes the electrostatic force between them? a) there's no force between them since one is neutral b)there's a force of repulsion between them c)there's a force of attraction between them Isn't it a...

**Physics**

For an electron moving in a direction of the electric field its potential energy _______ and its electric potential _________. Wouldn't the blanks be "increases" and "decreases"? because PE=mgh while V=kq/r

**Physics**

The equipotential lines inside a parallel plate capacitor a) circles clockwise b)circles counterclockwise c)radiates inwards d)radiates outwards e)runs parallel to capacitor plates f)runs perpendicular to capacitor plates I have narrowed it down to either e) or f) but I think ...

**Physics**

When discharging a capacitor it will a) loose half of its charge in equal time intervals b) loose a third of its charge in equal time intervals c) loose a quarter of its charge in equal time intervals d) gain half of its charge in equal time intervals I know that d) isn't ...

**Physics**

1)Several resistors are connected in series. If a battery provides constant voltage in this circuit the addition of another resistor in series a)increases current through each resistor b)decreases current through each resistor c)doesn't affect the current throught any ...

**Physics**

A circuit with a capacitor took .138s to discharge from its max charge Qmax to half of that max charge once the battery was removed. In this series circuit there also is one resistor with 100 G(ohm symbol). The voltage drop is 12V across the battery. a)How much time would it ...

**Physics**

A circuit with a capacitor took .128s to discharge from its max charge Qmax to half of that max charge once the battery was removed. In this series circuit there also is one resistor with 100 G(ohm symbol). The voltage drop is 12V across the battery. What is the time constant ...

**algebra**

m-450=1/4m -450=1/4m-1m -450=1/4m-4/4m -450=-3/4m -450*(-4/3)=m 600=m

**Physics**

If the TV draws a 150W of power, the dishwasher 1500 W of power and the computer 100 W of power, will a typical 15 A circuit breaker trip if they operate simultaneously on one line? Explain why. Isn't P= IV and P=I^2R and P- V^2/R So wouldn't that mean that as these ...

**Physics**

When Gorix escaped from Dr. Sloth's ship, his ship started at rest. Gorix immediately set his thrusters to full power, and his ship's acceleration increased by 2 m/s2 every second for 15 seconds. At that point, the ship remained at constant acceleration for another 30 ...

**Physics**

A sexond smaller metal sphere was positioned near the van de Graff machine. THe sphere was grounded. Did this snaller sphere become charged? How and why? was the interaction between the two spheres attractive or repulsive? Explain. Yes the smaller sphere was charged because ...

**Physics**

If the TV draws a 150W of power, the dishwasher 1500 W of power and the computer 100 W of power, will a typical 15 A circuit breaker trip if they operate simultaneously on one line? Explain why.

**Physics**

The following appliances are being used simultaneously: toster oven, TV, computer, three 100 W light bulbs and an iron. Yet the circuit breaker (15 A) has not tripped. Does that necessarily mean that not all of these appliacnces are connected to a single circuit? I am having ...

**Physics**

A battery with voltage drop of 120V is connected in a ciruit containing both series and parallel. Moving in a clockwise direction. R1= 3 ohms. Suddenly there is a connection of point A to point B. In between these two points is a parallel circuit with R2= 10 ohms and R3=2ohms ...

**Anatomy and Physiology**

A. Right to left B. proximal to distal C. anterior to ventral D. coronal to transverse The answer is B.

**Physics**

A battery with voltage drop of 120V is connected in a ciruit containing both series and parallel. Moving in a clockwise direction. R1= 3 ohms there is a connection of point A to point B. In between there is a parallel circuit with R2= 10 ohms to R3=2ohms on the top. On the ...

**vocabulary-sentences**

I need help doing my sentences By Andrea

**Physics**

You came across an egg that was a perfect sphere. You placed it in a tub of water and found that it displaced exactly 280,000 cubic centimetres. However, it was floating on the water, and only 72% of the surface area of the egg was below the water line. What was the total ...

**precalc**

We're not supposed to find it using arctan. We have to get one side to be 2 factors that equal zero when multiplied.

**precalc**

Solve sinx+cosx=0 Thanks!

**science**

You came across an egg that was a perfect sphere. You placed it in a tub of water and found that it displaced exactly 280,000 cubic centimetres. However, it was floating on the water, and only 72% of the surface area of the egg was below the water line. What was the total ...

**physics**

An electric charfe of -3 C is moved from a position where the electric potential is 1 V to a position where the electric potential is -6V. What is the chsange in potential energy of the charge with this change in position? I know that change in PE = k(q1q)/r_2 - k(q1q)/r_1 I ...

**Physics**

A block oscillates on a spring and passes its equilibrium position with a speed of .157m/s. It's kinetic energy is zero when the block is at the distance of .1m from equilibrium. Assume no friction between the block and the table. v=.157m/s KE =0J when x=.1m a)First I need...

**Physics**

A violin string is .32m and has a mass of .0005kg. The freqency of the note played is 440Hz. What is the speed of the wave in the string? .5*wavelenght = L wavelength= 2*.32m =.64m v=f(wavelength) =440hz*.64m =281.6m/s b) where must one put one's finger to play a note with...

**Physics**

A guitar string is .75m and has a mass of .005kg. A standing wave is produced when the string is plucked. a) what is the fifth harmonic if the tension in the string is 90N? v=sqrt(F_t/mass density)= 116m/s f1=v/2L = 116m/s/(2*.75m) =77.3Hz fn=n*f1 f5=5*77.3Hz =386.5Hz and to ...

**environmental science**

Why does the FEMA (Federal Emergency Management Area) only allow property owners to collect insurance if they rebuild in the same place and same way as before? Thanks!

**Physics**

A block oscillates on a spring and passes its equilibrium position with a speed of .157m/s. It's kinetic energy is zero when the block is at the distance of .1m from equilibrium. Assume no friction between the block and the table. v=.157m/s KE =0J when x=.1m a)First I need...

**Physics**

A block oscillates on a spring and passes its equilibrium position with a speed of .157m/s. It's kinetic energy is zero when the block is at the distance of .1m from equilibrium. Assume no friction between the block and the table. Force is 8.67N. Also mass displacement is...

**Physics**

Why do your vowels examples ("aaah", "eee", "uhh") sound different then when I make them? Explain. Tension, mass density and the length of our vocal cords differ so would that be the reason why they sound different? For instance: a child's ...

**Physics**

A musician plays the middle C note (262 Hz) on a guitar, a piano, and a violin at the same loudness. Will all three instruments produce exactly the same sound? Why or why not explain. Frequency (262Hz) is the same so that means that the pitch of the sound wave is the same. ...

**Physics**

Why do ocean waves break as they approach the shore? Is it because of the principle of superposition. Would it be described as constructive or destructive interference? I believe it's constructive interference as the two waves combine the amplitude is large which causes ...

**Physics**

A block oscillates on a spring and passes its equilibrium position with a speed of .157m/s. It's kinetic energy is zero when the block is at the distance of .1m from equilibrium. Assume no friction between the block and the table. What is the period of its oscillation? v=....

**Physics**

The frequency of a stationary siren is 1500 Hz when measured by a stationary observer. If an observer moves away from the siren at mach number .85 what is the frequency he hears? (assume room temperature so that velocity of the air is 340m/s) I know that I would use f'=f (...

**Trig**

Verify that each of the following is an identity. tan^2x-sin^2x=tan^2xsin^2x I can get it down to cos^2 on the right, but cannot get it to work out on the left. secx/cosx - tanx/cotx=1 On the left I got down to 1-tan^2, but that clearly doesn't equal 1.... 1-2cos^2x/...

**History**

Eisenhower

**history**

what is the slaves experiences in mid19th century america

**american history**

what businesses came under the scrutiny of the sherman antitrust act in the 1800s?

**precalc**

thanks

**precalc**

Hi. Can someone help me with this? Simplify: (sin^2x)(cos^2x)+(sin^4x) The answer is sin^2x, but I have no idea how to get there! Thanks!

**science**

Suppose you have monohybrid pea plants in your garden and find that they produce round seed to wrinkled seeds in the ratio of 3:1. If the allele are designated (R & r) respectively, what is the probable genotypes of the wrinkled seeds which were produced (F1)? RR & Rr RR only...

**Math**

Find the value of tan(1/2sin^-1 15/17) and sin[pi/2-cos(1/2)] Thanks.

**Math**

how would you factor 4x-x^2-3/ x-1...so that x-1 would cancel out? could you explain step by step..plz

**Physics**

A string of mass m=.1kg is stretched to where its length is L=20m. What is the tension force applied to the string if it takes a pulse 2 seconds to get from one end to the other? m=kg L=20m T=4s mass density =m/L = .1/20 = kg/m Tension =? I know v=sqrt(F_t/mass density) But I...

**Physics**

Find the instantaneous velocity of a pendulum at the instant when its bob is at the height equal to half of its maximum height h=(h_max/2) above the equilibrium point. Assume the max velocity of the bob during each oscillation is v_max= 2m/s. Wouldn't PE=KE mgh=1/2mv^2 gh=...

**Physics**

A swing is 2m long. how often do you need to push it to increase its swing's amplitude the most? L=2m When amplitude is the most KE=0 and PE is at its maximum. But i'm not completely sure how to solve this problem.

**Physics**

A mass m=.5kg on a spring with a spring constant. It is displaced by the distance x_max =20cm (.2m) from equilibrium on a frictionless horizontal surface. At the time t=0s the mass is released and it begins to oscillate. Assume that T=3.14s. Find the following for when t=0, T/...

**Physics**

Find the instantaneous velocity of a mass on a spring oscillating on a horizontal frictionless surface at the instant when its displacement is half of its maximum displacement x=(x_max/2). Assume the max velocity of that mass during each oscillation is v_max= 2m/s. I know that...

**Math**

Which type of dilation is determined by a scale factor of 10? enlargement reduction congruence transformation none of these

**math**

how would you solve for x? can you explain step by step? 40 = [(x+2.8)/2]*8.5

**Math : Algebra**

how would you solve for x? can you explain step by step? 40 = [(x+2.8)/2]*8.5

**Math : Algebra**

how would you solve for x in this equation? 40.0 = 0+ (x + 2.8)/2multiplied by(8.50)

**history**

Why did Germany invade Poland in 1941? =]

**History**

Why did Japan invade China in 1937? thank you so much =]

**History**

Why did Japan invade China in 1937? thank you so much =]

**Bio**

Describe what can happen to the three-carbon molecules made in the Calvin cycle.

**Physics**

A box of mass 1kg is placed on a table and is connected to a hanging mass m by a string strung over a pulley. If the coefficient of kinetic friction between the box and the table is .3 and the box slides at a constant speed of .5m/s what is the weight of the hanging mass? to ...

**Physics**

You have just discovered a planetary system consisting of a star (Dagobahr) and its two planets: Rool and Krau. Planet Rool has an average orbital radius 3 times as big as planet Krau. If planet Rool orbits Dagobahr in 2 earth years (1earth year = 365 days). a) how long is the...

**Physics**

A box of mass 1kg is placed on a table and is connected to a hanging mass m by a string strung over a pulley. If the coefficient of kinetic friction between the box and the table is .3 and the box slides at a constant speed of .5m/s what is the weight of the hanging mass? ...

**Physics**

A box of mass 1kg is placed on a table and is connected to a hanging mass m by a string strung over a pulley. If the coefficient of kinetic friction between the box and the table is .3 and the box slides at a constant speed of .5m/s what is the weight of the hanging mass? ...

**Physics**

complete the statement: in recoil a)the initial momentum is zero b)the object sticks together after collision c)the total kinetic energy is conserved d)the final speeds of the object are the same b) is wrong. I think it's either c) or d) but i'm going to go with c).

**Physics**

a rock is thrown straight up which of the following statemetns concerning the net force acting on the rock at the top of the path is true? assume air resistance is negligible. a)it's equal to the weight of the rock b) it is instantanwously equal to zero c) it's ...

**Physics**

two objects collide when sliding on a fricitonless horizontal surface. Which quantity is conserved during their collision? a) velocity b) momentum of both objects c)energy d) momentum of each object isn't c) or b) correct? I really think it's c)

**Physics**

a rock suspended from a string moves downwards at constant a=g. Which of the following is true concerning the tension in the string? a) the tension is zero b)the tension is equal to the weight of the rock c)the tension is less to the weight of the rock d)the tension is greater...

**Physics**

Complete the following statement: The term net force most accurately describes: a) quantity that causes displacement b) quantity that keeps the object moving c) the mass of the object d) the quantity that changes the velocity of an object c) is not the right choice. I believe ...

**Physics**

Europa, a moon of Jupiter has an orbital diameter of 1.34x10^9m and a period of 3.55 days. What is the mass of Jupiter? d=1.34x10^9m T=3.55days = 30672s M=? r=71492000m rm=6.7x10^8 r-total=7414492000m r^3/t^2=GM/4pi^2 741492000^3/306720^2=6.67X10^-11(M)/4pi^2 I got m=2.56x10^...

**Physics**

The mean radius of the Earth is R=6.38x10^6m. At what distance above the Earth's surface will the acceleration of gravity be 4.905m/s^2? F_g=(Gmme)/r^2 4.905=6.67x10^-11(5.98x10^24)/r^2 The mass cancel out so that is how I got the above answer. r=9017663m Is this the ...

**Physics**

A 2.1kg brass ball is transported to the Moon. a)What is the mass of the brass ball on the earth and on the moon? Wouldn't it be 2.1kg for the earth as well as for the moon? b)Determing the weight of thee brass ball on the earth. F_g=(G*m_ball*m_earth)/r^2 =20.58N c) the ...

**Physics**

"the total angular momentum of an object changes when a net external force acts on the system." This statement is: a)always true b) never true c) sometime true, it depends on the force's direction d)sometime true, it depends on the force's point of ...

**Physics**

A lever is 5m long. The distance from fulcrum to the weight to be lifted is 1m. If the worker pushes on the opposite end with 400N, what is the max weight that can be lifted? l=5m h=1m F=400N F_g=? torque=F_g*l I first must find torque so that I can plug it into the above ...

**Physics**

Is the answer to this 4? If the filament resistance in an automobile headlamp is 3 ohms, how many amps does it draw when connected to a 12-volt battery?

**Physics**

Consider a roller coster car moving along a track from point A to point B to point C. a)if the roller coaster car starts from rest at point A (30m above the bottom of a dip (point b). What would be the speed of the car at the top of the next hill (point C), which is 20 m above...

**Physics**

If the net work done on an object is positive then the object's energy is ...? The object's energy would also increase since W= energy right? The object's energy wouldn't increase or decrease.