Monday

April 21, 2014

April 21, 2014

Total # Posts: 219

**Math**

The formula for the velocity of an object is , where v is the velocity of the object, d is the distance traveled, and t is the time elapsed while that distance is traveled. v=d/t distance = speed times time so time in seconds = distance in meters / speed in meters/second we ne...

**Physics**

An inclined plane is used to raise a 100 kg box to a height of 5 m. How long must the inclined plane be if a force of 250 N is used to push the box up the inclined plane?

**physics**

In one dimension ,how does energy depend on size of region if an electron is confined there ??

**Phisics**

A violin string vibrates at 298 Hz when unfingered. At what frequency will it vibrate if it is fingered one sixth of the way down from the end?

**Phisics**

An object with mass 2.0kg is attached to a spring with spring stiffness constant 240N/m and is executing simple harmonic motion. When the object is 2.2Ã—10âˆ’2m from its equilibrium position, it is moving with a speed of 0.65m/s . Calculate the ampl...

**physical**

Libby pulls a 3.9kg box to the right with a force of 200 n at a 45 degree angle relative to the horizontal along a frictionless surface. What is the acceleration of the box?

**algebra**

What did the baby buzzard say when it say an orage in the nest

**Geometry**

Why don't you just follow the formula? V= pi r^2 h

**Maths**

The question is vague - I think it should have been, "How many more roses did A than B at first?" In this case, it's 14.

**6 grade math**

It is only adding 1 whole number to the fraction that make looks like improper fraction; say 1 1/4 = 5/4; adding 4/4 to 1/4. 4/4 is the fraction of 1 taken from the whole number 8 5/12 = 7 17/12 (added 12/12 to 5/12) 4 5/9 = 3 14/9 (added 9/9 to 5/9) 2 1/3 = 1 4/3 (added 3/3 t...

**science**

I think the first one is B. But I'm not for sure on that one. But the second one is output.

**Chemistry**

Although the VSEPR theory is correct in predicting that CH4 is tetrahedral, NH3 is trigonal pyramidal, and H2O is bent, the HNH angle in NH3 is only 107.3° and the HOH angle in H2O is only 104.5°. Explain these deviations from the expected tetrahedral angle of 109.5&de...

**science**

Newton’s law of universal gravitation is rep- resented by F=GMm r2 Here F is the gravitational force, M and m are masses, and r is a length. Force has the SI units kg · m/s2. What are the SI units of the proportionality constant G? 1. m2/(kg2 · s2) 2. m/(kg ...

**physics **

A plastic tube allows a flow of 14 cm3/s of water through it. How long will it take to fill a 240 cm3 bottle with water? Answer in units of s

**algebra**

Let U = {1, 2, 3, 4, 5, 6, 7}, A = {1, 2, 3, 4}, B = {1, 2, 5, 6}, and C = {3, 5, 7}. List all the members of the given set. (Enter your answers as a comma-separated list.)

**english**

revise the following sentences to eliminate shifts in tense, mood, voice or person. 7. The flight attendant said, "please turn off all electronic devices," but that we could use them again after takeoff. 8. The real estate market was was softer than it has been for a...

**math**

Oscar picked 12 apples. He gave 1/3 of the apples to Gil and 1/3 of the apples to Becky. How many apples did each of them?

**Science due tmrw**

Which simple machine does not change the direction of a force?

**Clueless in calculus**

Let f be the function be defined by f(x)=5^((2x^2)-1)^(1/2) A) is f an even or odd function? Justify answer. B) find the domain of f. C) find the range of f. D) find f'(x)

**Math Pre Cal **

Find the values of the trigonometric functions of è from the information given. cot è = 1/2 , sin è < 0

**physics**

How fast is a city on the earth's equator (such as Singapore) moving due to our planet's daily spin on its axis?

**Physics**

A test car travels in a straight line along the axis. The graph in the figure shows the car's position as a function of time

**Math**

if 3/5 of a group of children were girls, and there were 24 girls, how many children were in the group?

**Algebra 1**

Solve this proportion- 4/x+3=8/10

**Algebra 1**

Thank you, thank you, thank you, thank you!!!! I appreciate it very much! I worked on this for no lie, 30 minutes or so and could never get an answer that was one of the choices! Thank you soooooo much!

**Algebra 1**

A car travels on a highway at an average speed of 65 miles per hour. What was the speed in feet per second? (Remember- 1 mile=5280 feet)

**physics**

Solution of:An air plane ABC R=250m (x=30) the speed of the meachine is 450Km/h in A determine the accelartion supported by the pilot in A and the tangential accelartion is 10m.s determine the speed in B if the tangential accelaration is constant

**statistics**

1. 2.5

**Math (Algebra 1)**

Thank you for the explanation. I thought you maybe did everything on top and then divided the bottom number, but that didn't seem right. Thanks a lot though!! You were great help! :)

**Math (Algebra 1)**

I thought that was the answer, but I wasn't sure if I should do the division first because of order of operations?

**Math (Algebra 1)**

2y-z --------- for x=-3, y=13, z=5 x

**math**

thank you so much

**math**

The price of an oven changes from $450 to $396. (1 point)13.6% increase 13.6% decrease 12% increase 12% decrease

**physics**

A car of mass m = 1635 kg is pushed off a cliff of height h = 23 m. If the car lands a distance of 9 m from the base of the cliff, what was the kinetic energy of the car the instant after it left the cliff?

**Physics**

Calculate the velocity of a satellite moving in a stable circular orbit about the Earth at a height of 2600 km.

**math**

a 15 ft ladder is palced against a wall such that its base is 9 ft away from the wall. if the base of the ladder is moved to 6 ft away from the wall, by about how much will the top of the ladder move up the wall?

**science**

what would be the complementary strand of DNA be for the following sequence of bases? C T T A G G C T T A C C A I'm stuck please help! my guess was ATTGCCATTGCCA

**algerbra**

Donna deposits into an account that pays simple interest at a rate of 5% per year. How much interest will she be paid in the first 6 years?

**Physics**

Find the force of tension in the chain. Determine the force of compression in the support bar. Be sure to include a free body diagram as part of your solution. Now the only information given is a mass=20.4 kg and the angle 22 degrees. If anyone could help me with this question...

**Physics- grade 12**

A ramp leading up to a loading platform is 3 m long and 1 m high at its highest point. If the friction is ignored, what work is needed to slide a 600-kg crate up the ramp at a constant speed? a) 2.00 *10^2 J b) 5.89 *10^2 J c) 1.80 *10^3 J d) 5.88 *10^3 J I believe the answer ...

**Physics**

In this problem they show a diagram of a pulley system with an inclined plane (25 degree incline). There is a box called m1=47kg resting on the incline plane and m1=35kg hanging on the vertical line. The question reads: The coefficient of friction between m1 and the surfvace o...

**Physics - grade12**

for some reason by multiplying the answer that I got for the "mass added" by 35kg, this gave me the answer at the back of the book

**Chemistry - Mole Ratio**

How many moles of oxygen are produced from the decomposition of 3.4g of hydrogen peroxide? How many molecules of O2 are produced?

**math**

thanks

**math**

is this not always true? because the square of 0.5 is 0.25 and that is less than the number, but the square of 3 is 9 which is greater than 3.

**math**

please help! is the square of a number greater than the number?

**math**

thanks so much ! have a blessed day/night

**math**

Those are the answer choices

**math**

A) r +.20 B) r + .15 C).15r D) 3R + .15

**math**

or each month jack works he earns an increase or raise of $. 05 on his hourly pay if he has already worked for three months, which shows his 4th month's hourly rate in terms of his first month's hourly rate?

**Algebra**

A weekly order is 10 gallons of coke to 15 gallons of 7up. What is the ratio of 7up to coke?

**Algebra **

A road map uses a scale of 3 cm for every 5 miles. How many miles are there in 9.5 cm?

**Chemistry**

What is the volume of a scuba tank if it takes 2000 L of air collected at 1.00 atm to fill the tank to a pressure of 150 atm? T is constant.

**Chemistry**

A hot-air balloon has a volume of 4.000 x 10^5 L at 30 degrees celsius and a pressure of 748 mmHg. If the average molar mass of air is 29.0 g/mol, what is the mass of air in the balloon?

**Chemistry**

Apply the gas laws to determine how many grams of sodium azide (NaN3) are needed to fill the air bag of your vehicle to a volume of 79.0 L at 35.0 degrees celsius and 1.00 atm. The reaction occurring in the air bag can be repesented by the equation, 2NaN3 (s)-> 2Na (s) + 3 ...

**Chemistry**

The combustion of methane can be described by the equation: CH4 (g) + 2 O2 (g) -> CO2 (g) +2H20 (g) If 22.0 mL of CO2 (g) were collected, what volume of H20 (g) also could be collected under the same conditions?

**Chemistry**

a helium balloon is partially filled with 28.7 L of gas at 25.0 degress celcius and a pressure of 1 atm. if the balloon is released and it floats up intp the atmosphere to a heightwhere the pressure is 2.8 x 10^-3 atm and the temperature is -24.0 degrees celcius, calculate the...

**math**

its 20 by 30

**math**

80 goldfish and it doesn't say how deep the aquarium it just says its a 20X30 square inch rectangular aquarium

**math**

what is the population density if your goldfish population was found in 20x30 sq inch rectangular aquarium?

**chemistry**

Predict whether nitrate salt solutions containing metal ions with the following outer shell electron configurations will be colored or colorless: [Ar] 3d^2 and [Kr] 4d^10

**trig**

write a product of two trig functions that equals 1.

**Chemistry**

Potassium, K, is more reactive than sodium, Na. Calcium, Ca, is less reactive than sodium. The comparative reactivity of these metals is often noted as: K > Na > Ca. Explain the reactivity differences of K, Na, Ca.

**statistics**

The profit for a new product is given by Z = 2X - 2Y - 7. We know that X and Y are independent random variables with Var(X) = 2 and Var(Y) = 2.7. What is the variance of Z?

**math**

Is 1 greater than or less than negative 1?

**chemistry**

the activity series of metals is: Au < Ag < Cu < Sn < Cd < Zn < Al < Mg < Na < Cs which reaction below occutrs spontaneously upong mixing the reageant shown? a) Sn(s) + Al3+ (aq)-> sn2+(aq) + al(s) b) sn(s) + zn 2+ (aq) -> sn 2+ (aq) +zn (s) c)...

**Chemistry**

Thank you!

**Chemistry**

You observe that when copper is added to a soltion containing gold ions, the copper dissolves and the gold precipitates. Similarly, almost every other metal will displace gold from solutions of gold salts. a) Do these observations mean that gold ion is a unusally good oxidizin...

**Science **

Unrelated species may come to resemble one another over many generations due to

**algebra**

what is (5x^2-4)+(-3x^2-9)? thanks

**Physics**

An arrow is shot at a 30 degree angle with the horizontal. It has a velocity of 49m/s. The acceleration of gravity is 9.8 m/s2. How high will the arrow go?

**Physics**

An arrow is shot at a 30 degree angle with the horizontal. It has a velocity of 49m/s. The acceleration of gravity is 9.8 m/s2. How high will the arrow go?

**Physics**

An arrow is shot at a 30 degree angle with the horizontal. It has a velocity of 49m/s. The acceleration of gravity is 9.8 m/s2. How high will the arrow go?

**scientist**

Scientists performed an experiment to determine whether there is a connection between learning ability and food. They took two groups of 20 mice each, all from the same purebred strain. The mice were deprived of food for 3 days and then given a standard learning session in ru...

**Math**

3(7-4)^2??

**Physics**

Two forces are applied to a car in an effort to move it, as shown in the following figure, where F1 = 402 N and F2 = 364 N. (Assume up and to the right as positive directions.)(F1 is 10degrees and F2 is 30degrees) (a) What is the resultant of these two forces? magnitude direct...

**Physics**

Two objects with masses of 1.00 kg and 7.00 kg are connected by a light string that passes over a frictionless pulley as in the figure below. (a) Determine the tension in the string. (b) Determine the acceleration of each object. (c) Determine the distance each object will mov...

**Physics**

An outfielder throws a 0.150 kg baseball at a speed of 26.0 m/s and an initial angle of 30.0°. What is the kinetic energy of the ball at the highest point of its motion?

**Physics**

A 7.80-g bullet moving at 530 m/s penetrates a tree trunk to a depth of 6.2 cm. (a) Use work and energy considerations to find the average frictional force that stops the bullet. (b) Assuming the friction force is constant, determine how much time elapses between the moment th...

**Physics**

A ski jumper starts from rest 51.0 m above the ground on a frictionless track and flies off the track at an angle of 45.0° above the horizontal and at a height of 12.0 m above the ground. Neglect air resistance. (a) What is her speed when she leaves the track? (b) What is ...

**Physics**

A rifle with a weight of 30 N fires a 3.0 g bullet with a speed of 250 m/s. (a) Find the recoil speed of the rifle. (b) If a 675 N man holds the rifle firmly against his shoulder, find the recoil speed of the man and rifle. I got .245 m/s for the first one but I keep getting t...

**Physics**

A cannon is mounted on a railway flatcar, the muzzle elevated to 31.4° and pointed in the direction of the track. The cannon fires a 1.10-metric-ton projectile at 1.10 km/s. (a) If the flatcar and cannon together have a mass of 36.0 metric tons (not including the projectil...

**Physics**

An electric motor rotating a workshop grinding wheel at a rate of 95 rev/min is switched off. Assume the wheel has a constant negative angular acceleration of magnitude 2.40 rad/s2. (a) How long does it take for the grinding wheel to stop? (b) Through how many radians has the ...

**Physics**

A 55.0 kg ice skater is moving at 4.04 m/s when she grabs the loose end of a rope, the opposite end of which is tied to a pole. She then moves in a circle of radius 0.795 m around the pole. (a) Determine the force exerted by the horizontal rope on her arms. (b) Compare this fo...

**Physics**

objects with masses of 285 kg and a 585 kg are separated by 0.420 m. (a) Find the net gravitational force exerted by these objects on a 62.0 kg object placed midway between them.

**physics**

A solid, horizontal cylinder of mass 8.0 kg and radius 1.30 m rotates with an angular speed of 5.50 rad/s about a fixed vertical axis through its center. A 0.250 kg piece of putty is dropped vertically onto the cylinder at a point 0.900 m from the center of rotation, and stick...

**Math**

Lawrence records the number of minutes he reads each day show below Day 1: 75 mins Day 2: 30 mins Day 3: 25 mins Day 4: 50 mins Day 5: 80 mins How many minutes must Lawrence read on the sixth dat of have mean of 55 minutes read for the 6 day?

**Math**

Triangle ABC is an obtuse triangle with two congruent angles. If m< C = 108 write an expression that represents m<A

**smk n2 **

Tent. sudut yang lebih kecil dari perpotongan bidang 5x-14y+2z-8=0 dan 10x-11y+2z+5=0 (tent sudut antara normal-normalnya)

**Math**

What is probability

**Math**

What is probability

**Calc**

The temperature at any point in the plane is given by function f(x,y) = 100/(x^(2)+y^(2)+1). Find a direction at the point (3,2) in which the temperature does not increase or decrease. Help, please? Thank you.

**Calc**

The directional derivative of z = f(x,y) at (2,1) in the direction toward the point (1,3) is -2/sqrt(5), and the directional derivative in the direction toward the point (5,5) is 1. Compute dz/dx and dz/dy at (2,1). I have no idea how to solve this problem. Help, please? Thank...

**MATH**

A rectangular flower is 20 inches long,8 inches wide ,and 6 inches high . True of false. If andy fills the flower pot 2/3 full of soil, the expression 2/3(20 + 8 + 6) could be used to find the about of soil he needed.

**ALGEBRA**

i need help with this problem

**Chemistry Help!!**

a kilogram of aluminum metal and a kilogram of water are each warmed to 75 degree Celsius and placed in two identical insulated containers. one hour later, the two containers are opened and the temperature of each substance is measured. the aluminum has cooled to 35 degree Cel...

**Physics**

A 14,245N auto with a velocity of 6.0m/s crashes into a brick wall. If the car moves 64.0 cm before coming to a stop, what average force does the car exert on the wall?

**Physics**

A 14,245N auto with a velocity of 6.0m/s crashes into a brick wall. If the car moves 64.0 cm before coming to a stop, what average force does the car exert on the wall?

**math**

80.00

**chem: gases, liquids, solids**

How many kilojoules of heat is required to completely covert 60.0 grams of water at 32.0° C to steam at 100°C? For water: s = 4.179 J/g °C (delta)H fusion = 6.01 kJ/mol (delta)H vap = 40.7 kJ/mol