# Posts by Scott

Total # Posts: 2,570

Physics
the energy is proportional to the SQUARE of the compression 4^2 = ?

Math
multiply the percentage (as a decimal) by the total number of students (500) to find out the numbers for the various sports then subtract the basketball number from the football number

Math
the built in Windows calculator (in scientific mode) works pretty well

Math
there are 365 compounding periods per year [1 + (.03 / 365)]^365 = 1 + APY

chem
the pressure is proportional to the absolute (Kelvin) temperature 1.89 / (24.0 + 273) = p / (38.0 + 273)

SCIENCE
for EQUAL branches total r = branch r / # of branches

Math
5.00 + (0.65 * x) = 10.00 + (0.45 * x) .20 x = 5.00

Physicd
7 N?s - 5 N?s = 2 N?s m v = 2 N?s m = 2/5 kg

Algebra
the slope means that the candle shortens by .4 cm per hour of burning how much taller would it be nine hours earlier? (how much did it shrink in nine hours?)

math
s + c = 72 / 3 s - c = 72 / 4 add the equations (to eliminate c) solve for s substitute back to find c

math
m?CAB = m?CBA = 30º m?BCM = 90º BM = 24 ... 30-60-90 TRIANGLE AM = CM

science
RL and LR are brown eyed but carry the blue recessive they represent half of the population

math
there are two "integer" multiples of 2 A 0.25 = 2^-2 B .05 = 2^-1

Maths
each component has an 80% chance of being good so the probability of a good (not defective) product is ... .8^4 probability of a defective product is ... 1 - .8^4

Physical Science
pH + pOH = 14 pOH = 12 [OH] = 10^-12

Pre-cal
s = 2 f - 5 s + f^2 = 115 f^2 + 2 f - 5 = 115 f^2 + 2 f - 120 = 0 (f + 12)(f - 10) = 0 f - 10 = 0 ... f = 10

Math
did you see the two sig fig part? 210000

SCIENCE
think you're right

Maths
the 8th term is 5 differences from the 3rd term, and 7 differences from the 1st term e = 2 t = 2 (f + 2 d) f + 7 d = 2 f + 4 d ... 3 d = f sum8 = 8 f + 28 d = 39 substituting ... 24 d + 28 d = 39 ... 52 d = 39 ... d = 3/4 substitute back to find f

math
there are 36 inches in a yard 580 / 36 = ?

Vv = V sin(30º) = ?(2 g h) Vh = V cos(30º) = Vv / tan(30º)

Chemistry
for the given volumes (22.5 + 22.5) * (30.17 - 23.50) * 1.00 ... * 4.184

Chemistry 11
looks fine

Math
the area is the average of the bases, multiplied by the height divide the area by 12 to find the number of boxes needed remember to round up to the next WHOLE number, if necessary

Chemistry
temp change times mass of H2O times specific heat of H2O (37.8 - 21.6) * 100 * 4.179 remember sig fig

Physics
momentum is conserved Mb * Vi = (Mb + Mw) * Vf Vi = (.005 + 8) * 0.50 / .005

Physics
frictional force is the normal force multiplied by the coefficient in this case ... Ff = Ma * g * 0.25 the frictional force keeps A moving with B ... so the max acceleration (without slip) is ... Ma / Ff the max force is the max acceleration multiplied by the sum of the masses...

Physics
1/2 m (v sin(60º)^2 = m g 10 km v = ?(g * 20 km) / sin(60º) this is the minimum velocity for the projectile to reach the height of the plane ... faster would be better

Physics
the weight change in the kerosene is the weight of kerosene displaced by the solid if the solid were kerosene, its weight would be 1.6 g ... (4.8 - 3.2) so the density ratio is ... 4.8 / 1.6

Chemistry
in (a) and (b), the hydroxides are probably in solution and the hydrogen is evolved as a gas

pre calc
the full solution is in the related questions at the bottom of the page

pre calc
the two given population numbers only have one significant digit either 670000 or 700000 is what the computer is looking for

Chemistry
the drops happen, but are not counted the fewer the drops to the endpoint, the lower the concentration of the unknown the concentration would appear to be lower than it actually is

physics!
velocity = circumference / period v = (2 * ? * 11.30 m) / 16.60 s plug it in and crank the crank

pre calc
1.7 = e^0.01t ln(1.7) = 0.01 t 100 ln(1.7) = t

Math
(300 * 200) - (280 * 180)

Physics
the centripetal acceleration is ... v^2 / r a) v^2 / r = g ... v^2 = 500 m * 9.8 m/s^2 b) his weight will be twice normal ... w = 2 * 80 * g

physics
95 km/h = 26.4 m/s 26.4 / 4.2 = stopping time (26.4 + 0) / 2 = ave stopping speed

Math
y varies inversely with x ... x y = k 25 * 5 = 125 ... x y = 125

math
the solution is the intersection of the lines

Physics
f = 1 / cycle time = 1 / (34.8 / 15)

pre calc
100 * 1/2 * 1/2 = 25 12 days = 2 half lives OR 1/4 = e^(12k) ln(1/4) = 12 k [ln(1/4)] / 12 = k ln(1/2) = k t t = ln(1/2) / {[ln(1/4)] / 12} = 6

geometry
it gives you the size of the interior angles of a regular polygon of n sides

math
90º is a quarter of a circle 1/4 * 1/4 = ?

Algebra
.9 x + 6.8 = .65 x + 7.3

science
the weight (force) of 50 kg is ... 50 kg * g ... g is the acceleration by gravity 200 * d = 50 * g * (2 - d)

Pre calc
pop = 900000 * k^t 800000 = 900000 * k^2 8/9 = k^2 ... k = 2?2 / 3 p = 900000 * (2?2 / 3)^5

Math
no ... is imaginary ... and irrational

Math
no ... is imaginary

science
a = f / m = 5224700 / 13500

Algebra
the corners are now three times farther from the origin just multiply each coordinate by 3

Physics
the beam weight is 50.3 N/m when Suki crosses a support to some distance (d), the equilibrium equation is ... (100.6 N * 1.00 m) + (595 N * d) ... = (251 N * 2.50 m) the distance from the end is ... 2.00 m - d

Algebra2
this is a circle, centered at the origin the domain and range are the same

Math ASAP
looks good

Math
180º - 65º - 65º = ?

Calculus
d = 2 r = 3 h ... r = 3/2 h v = 1/3 * ? * r^2 * h v = ?/3 * 9 h^3 / 4 dv = 9 ? h^2 dh / 4 dh = 4 dv / (9 ? h^2)

Physics
the incident angle is measured relative to the normal to the surface 90º - 60º = 30º

Physics!
.4 * 3000 = f (in Joules) 1) ma = 0utput / input = 3000N / 1000N 2) not enough info

Math
n, n+2, n+4 4(n+2) = n + n+4 + 2

Physics
that is the compression of the spring the more it's compressed, the greater the force

Physics
f = m a ... a = f / m a = (315 N * .15) / .00446 kg a is in m/s^2

Physics
ave speed = 1.4 rad/s stop time = 2 * ? * 60 / 1.4 acceleration = 2.8 rad/s / stop time ... negative ... wheel is stopping 30 * 2 * ? = 1/2 a t^2 + 2.8 t ... solve for t

Precalc
look at half the center 3rd it is a sector of the circle, with right triangles on either side the area of the sector is ... ? * r^2 * (?/360) ... ? being the central angle the combined area of the two triangles is ... r sin(?/2) * r cos(?/2) = r^2 tan(?/2) ? r^2 / 6 = r^2 [tan...

math
PEMDAS is the hierarchy of operations Parentheses...exponentiation ...multiplication...division ...addition...subtraction things in parentheses 1st ... 7^2 = 49 ...4 * 10 = 40 ...40 - 49 = -9 7 * -9 = -63 -63 + 4 = -59

math
.18 x + .40(10 - x) = .20 * 10

Math
like slicing bologna trees are cut on a "bias" to control the direction of fall

Math - Trig
Two buildings of equal height are 850 feet apart. An observer on the street between the buildings measures the angles of elevation to the tops of the buildings as 29° and 40°. How? high, to the nearest? foot, are the? buildings? I don't know how to set this up

Trig
the angle at the base of the pole is ... 90º - 8º the angle at the end of the shadow is the sun's angle the 3rd angle is opposite the 20 ft shadow use the law of sines to find the pole

Physics
the energy to lift the water is ... m g h = 10 kg * 10 m/s^2 * 10 m ... = 1000 J the kinetic energy of the water at delivery is ... 1/2 m v^2 ... = 1/2 * 10 kg * (10 m/s)^2 ... = 500 J 1500 J / s = 1500 watts = 1.5 kw

math
(1 - .75) * ? * 4 * r^2

maths
like the other one ... 5-12-13 tan = 12/5 sin = 12/13 cos = 5/13 cos(90 - ?) = sin (?) fyi ... holding down the 'alt' key while typing '233' will generate the '?'

maths
this is a 5-12-13 triangle cos = 5/13 tan = 12/5

Chemistry
don't know if sulfuric is moral or not ... however, it is diprotic (two H+) ?M = .16 * 25/17 * 1/2

CIS
1. you have 1GB and want to have 4 GB ... 2 open slots means a 1 GB and a 2GB module 2. 4 slots with 2GB each means max memory of 8GB

Physic
(a) w = m g (b) equal to weight (c) f = m a = 500 * 2.5 (d) moving (kinetic) (e) k = (7000 - 1250) / (m g)

Physics
some strike... impulse = change in momentum i = .34 kg (31.3 m/s - -6.18 m/s)

Physics
missed part (a) (a) voltage = [?(11.4/29.5)] * total R

Physics
I^2 = W / ? = 11.4 / 29.5 calculate I the resistors add in series power = I^2 * total R

Math help plz?!!
looks like your calculator is set on radians try again with degrees nearest hundredth is two decimal places

Math! Help Hurry!
same y-coordinates a vertical line length is the difference of the x-coordinates

Maths
think you are correct the question says p.a. (per annum) 58.7 is all four years ... divide it by 4

maths trigonometry
cos ? + 1 = 0 ... cos ? = -1 ... ? = ? tan ? - 1 = 0 ... tan ? = 1 ... ? = ?/4 , 5?/4

Math(precalc)
the logs are just (messy) numbers that you can distribute, add, subtract... [4 log(4)] x - 3 log(4) = ... [9 log(3)] x - 6 log(3) grind away...

Algebra
seven three with one top three with 2 top one with three top

Physics
e = (wavelength / c) * h c = speed of light h = Planck's constant

math
a square has FOUR equal sides 4 * 1/3(x+2) = 4/3 x + 8/3 = P 4/3 x = P - 8/3 4 x = 3 P - 8 x = 3/4 P - 2

Biomechanics
so what is her vertical velocity after one second? you found the correct acceleration

Algebra, Math
.3 x + [.1 (500 - x)] = .25 * 500

math
(x + 5)^2 + (y - 2)^2 = 676 plug in the points to check if they lie on the circle

Science- Astronomy
venus is closer to the sun and has a shorter "year" earth has a moon but venus has none

science
because the moon is between the Earth and the Sun the sunlight reflected off the moon, that we normally see, is pointed away from us this is when solar eclipses can occur

Álgebra
2 * [(8 * 14) + (8 * 10) + (10 * 14)]

Math
5C3 = 10

Math
inverse ... y gets smaller as x gets bigger x y = 10

physics
the KE of the bullet e = 1/2 * .02 kg * (150 m/s)^2 answer is in Joules

SAT Math
4/3

Chemistry
these values are negative logarithms of the concentrations so a bigger number means a lower concentration

Science
work = f * d = 60 * 2 = 120 J power = work / time = 120 / 10 = 12 W work is in Joules and power is in Watts

homework
36 m times 4 lengths per day times 7 days per week times 4 weeks

Science
the mass (in kg) multiplied by the gravitational acceleration (in m/s^2) gives the weight in N (Newtons) w = .0585 kg * 9.8 m/s^2 w = .04593 kg * 9.8 m/s^2 the g value is 2 sig fig, so that is what the answer will have