Sunday

May 29, 2016
Total # Posts: 3,443

**physics**

A cyclist enters a curve of 30 m radius at a speed of 12 m s-1. He applies the brakes and decreases his speed at a constant rate of 0.5 m s-2. Calculate the cyclist’s centripetal (radial) [3 marks] and tangential [15 marks] accelerations when he is travelling at a speed ...
*February 28, 2012*

**physics**

During a throw an athlete exerts a net average torque of 100 Nm on a discus about its axis of spin. The mass of the discus is 2 kg and its radius of gyration about its spin axis is 12 cm. If the discus was not spinning at the beginning of the throw and the throwing action ...
*February 28, 2012*

**physics**

An athlete is supporting a weight of 200N in his hand with his forearm at a right angle to his biceps. Assuming his biceps are in the vertical plane, the axis of rotation of the forearm is 3 cm from the elbow and 25 cm from the centre of gravity of the weight, calculate the ...
*February 28, 2012*

**physics**

A boy of mass 23 kg sits on a seesaw 1.5 m from the axis of rotation. At what distance from the axis of rotation must his friend, whose mass is 21 kg, be positioned to balance the seesaw? [6 marks]
*February 28, 2012*

**physics**

As part of a training schedule a weightlifter pushes a heavy metal block along the floor. The lifter applies a force of 850 N downwards on the block at an angle of 65° to the vertical (25° to the horizontal). The weightlifter pushes the block forwards 4 m in 1.6 s. ...
*February 28, 2012*

**physics**

A puck of mass 5.0 kg moving at 16.5 m/s approaches an identical puck that is stationary on frictionless ice. After the collision, the first puck leaves with a speed v1 at 30º to the orginal line of motion. The second puck leaves with speed v2 at 60º. The speed v1 ...
*February 26, 2012*

**physics**

A puck of mass 5.0 kg moving at 16.5 m/s approaches an identical puck that is stationary on frictionless ice. After the collision, the first puck leaves with a speed v1 at 30º to the orginal line of motion. The second puck leaves with speed v2 at 60º. The speed v1 ...
*February 26, 2012*

**3 grade english**

Jimmy likes checkers, and he is very good at playing it with his mom. Pronouns are "he" and "it" They have lots of fun playing it because they spend time together. Pronouns are "They" and "it" Sometimes, Jimmy's dad plays with them, ...
*February 24, 2012*

**Chem**

how much energy is required to change 42.5 g of molten aluminum into aluminum vapor
*February 22, 2012*

**Living ENvironment**

no am doing a project and i have to label the parts of the diagram if they are enzyme/substrate complex , active site and etc
*February 22, 2012*

**Living ENvironment**

Where is the Enzyme/substrate complex
*February 22, 2012*

**Physics**

A computer is reading data from a rotating CD-ROM. At a point that is 0.0368 m from the center of the disk, the centripetal acceleration is 274 m/s2. What is the centripetal acceleration at a point that is 0.0781 m from the center of the disc?
*February 19, 2012*

**Physics**

Two satellites are in circular orbits around Jupiter. One, with orbital radius r, makes one revolution every 18 h. The other satellite has orbital radius 3.9r. How long does the second satellite take to make one revolution around Jupiter?
*February 18, 2012*

**Chemistry**

KI+H2SO4 Write the balanced net ionic equation.
*February 17, 2012*

**Chemistry**

NaBr+H2SO4 Write the balanced net ionic equation.
*February 17, 2012*

**Chemistry**

NaCl+H2SO4 Write the balanced net ionic equation.
*February 17, 2012*

**Chemistry**

3Ag(s)+4HNO3(aq)-->3AgNO3(aq)+NO(g)+2H2O(l) Write the net ionic equation.
*February 17, 2012*

**3rd grade math**

write the missing fraction or mixed number for each number line 0,1/3,2/3,1,____,____,____,______,2 1/3 3
*February 16, 2012*

**Chemistry**

This topic's pretty old, but I figured it would be worth it to have the new way to solve the problem posted as well. If you're like me you're a young whippersnapper who's never even heard of normality. It's actually not as hard as DrBob says. Molarity = ...
*February 16, 2012*

**english**

2. Marion needs to believe in a ____ (1 point)
*February 15, 2012*

**Math**

76 girls
*February 13, 2012*

**College Chemistry**

If the density of cylinder 1 is 3.55 , what is the density of cylinder 2? (The masses and volumes of two cylinders are measured. The mass of cylinder 1 is 1.35 times the mass of cylinder 2. The volume of cylinder 1 is 0.792 times the volume of cylinder 2.)
*February 12, 2012*

**math**

If a metal ball is thrown downward with an initial velocity of 22 feet per second (15mph)from a 100 foot water tower, it's height h in feet above the ground after t seconds is modeled by h(t)=-16t^2-22t+100 Determine when the height of the ball is 62 feet.
*February 12, 2012*

**algebra**

The strength of a wood beam varies inversely with its length. A beam is 33 feet long can support 1200 pounds. How much weight can a similar beam support if it is 23 feet long?
*February 11, 2012*

**maths/physics/biomechanics**

At the beginning of a race, a yacht crosses the start line and sails in westerly direction at a speed of 4 m s-1. The current of the sea is flowing at 2 m s-1 towards the north-east. Calculate how far [8 marks] and in what direction (relative to west) [8 marks] the yacht has ...
*February 9, 2012*

**chemistry**

Which of the following isotopes possesses a greater number of electrons than it does neutrons? A. 40Ar B. 24Mg2+ C. 34S2− D. 19F− E. 16O2− How do I determine the numbers of protons, neutrons, and electrons of each?
*February 9, 2012*

**physics**

A 2.00kg bullet moving at 600m/s strikes a piece of wood at rest on a frictionless table. The bullet sticks in the wood and the combined mass moves slowly down the table. a.) What is the speed of the combined mass after the collision? b.)What is the change in kinetic energy of...
*February 9, 2012*

**chemistry**

A graduated cylinder was used to transfer 201 mL of a 0.478 M solution of KCl to a beaker which was subsequently diluted to a final volume of 1.092 L. What is the final molarity of the KCl in the beaker after the solution is thoroughly mixed?
*February 8, 2012*

**Chemistry**

thanks!
*February 8, 2012*

**chem**

How many grams of water vapor (H2O) are in a 10.2 liter sample at 0.98 atmospheres and 26°C? Show all work used to solve this problem.
*February 8, 2012*

**Chemistry**

rate is 1.1 ng/dL-hr
*February 8, 2012*

**Chemistry**

A deceased person is found by the coronoer to have a cocaine concentration of 50 ng/dL. What is the concentration of cocaine in his blood two hours earlier?
*February 8, 2012*

**mth174**

A tank is full of water. Find the work W required to pump the water out of the spout. (Use 9.8 for g and 3.14 for π. If you enter your answer in scientific notation, round the decimal value to two decimal places. Use equivalent rounding if you do not enter your answer in ...
*February 7, 2012*

**maths**

At the beginning of a race, a yacht crosses the start line and sails in westerly direction at a speed of 4 m s-1. The current of the sea is flowing at 2 m s-1 towards the north-east. Calculate how far [8 marks] and in what direction (relative to west) [8 marks] the yacht has ...
*February 7, 2012*

**maths**

Two athletes are pulling on a ring. One athlete pulls with a force of 150 N in a northerly direction. The second athlete pulls with a force of 200 N in a westerly direction. Calculate the magnitude [5 marks] and direction (relative to west) [5 marks] of the resultant of these ...
*February 7, 2012*

**physics**

A 75 kg skydiver in free fall is subjected to a crosswind exerting a force of 60 N and to a vertical air resistance force of 100 N. Calculate the resultant force acting on the skydiver [6 marks] and his angle of fall (relative to vertical) [6 marks].
*February 7, 2012*

**Physics**

A driver in a car traveling at a speed of 56.0 mi/h sees a deer 116 m away on the road. Calculate the minimum constant acceleration that is necessary for the car to stop without hitting the deer (assuming that the deer does not move in the meantime).
*February 2, 2012*

**Physics**

I have found that it takes the lead car 11.95 s to stop and it traveled 146.4 m. But still need help with the rest.
*February 2, 2012*

**Physics **

Two cars are traveling along a straight line in the same direction, the lead car at 24.5m/s and the other car at 29.8m/s. At the moment the cars are 41.4m apart, the lead driver applies the brakes, causing her car to have an acceleration of -2.05m/s2. A) How long does it take ...
*February 2, 2012*

**Physics **

Two cars are traveling along a straight line in the same direction, the lead car at 24.5m/s and the other car at 29.8m/s. At the moment the cars are 41.4m apart, the lead driver applies the brakes, causing her car to have an acceleration of -2.05m/s2. A) How long does it take ...
*February 2, 2012*

**Physics**

tortoise= 10.1 t hare= 195.94(t-122) tortoise - hare= 10.1t - 195.94t + 23904.68 = 20.8 Solve for t 23883.88 = 185.84 t t = 128.5185 s tortoise t= (10.1)(128.5185)= 129.036 cm
*February 2, 2012*

**Math**

afraaz the answer of 12.5 is not correct, i had done the same math as you did, however the teacher said that the answer was wrong.
*February 1, 2012*

**Physics**

A diver springs upward from a board that is 4.10 m above the water. At the instant she contacts the water her speed is 11.9 m/s and her body makes an angle of 79.7 ° with respect to the horizontal surface of the water. Determine her initial velocity, both (a) magnitude and...
*January 31, 2012*

**math**

17*5=85 17+5=22
*January 31, 2012*

**physics**

I found the answer to part a, but I don't know how to solve part b. Part is 26.1m/s.
*January 31, 2012*

**physics**

A space vehicle is coasting at a constant velocity of 22.5 m/s in the +y direction relative to a space station. The pilot of the vehicle fires a RCS (reaction control system) thruster, which causes it to accelerate at 0.223 m/s2 in the +x direction. After 57.5 s, the pilot ...
*January 31, 2012*

**math**

math : write an equation that uses 18-?and 10+2.explain how to decide which numbers would make it true.
*January 30, 2012*

**Math**

Red and blue beads are being strung to make a bracelet. How many different bracelets can be formed it each bracelet uses exactly 5 beads?
*January 29, 2012*

**geometry**

Simplify the ratio: 48 ft. -------- 36 ft.
*January 27, 2012*

**Organic Chemsitry**

Hey Saj how did you get 5.5 as the answer?
*January 27, 2012*

**Problem Solving: Make a Table**

1st week=$50 2nd week=$75 3rd week=$100 4th week=$125 5th week=$150 6th week=$175 7th week=$200 TOTAL=$875
*January 25, 2012*

**World History**

28.Olympe de Gouges
*January 23, 2012*

**physics**

In reaching her destination, a backpacker walks with an average velocity of 1.20 m/s, due west. This average velocity results, because she hikes for 5.94 km with an average velocity of 3.28 m/s due west, turns around, and hikes with an average velocity of 0.778 m/s due east. ...
*January 22, 2012*

**Physics**

Two iron spheres each have a volume of 10 cm^3 and a mass of 78g. How many electrons must be placed on each sphere so that the electrostatic force of repulsion between them just balances the force of gravitational attraction? Assume the distance between the spheres is more ...
*January 21, 2012*

**science/anatomy**

1. pharynx 2. Epiglottis
*January 19, 2012*

**math**

I had the same question
*January 19, 2012*

**geometry**

the transamerica pyramid building shown in the photograph has four faces shaped like isosceles triangles. The measure of a base angle of one of these triangles is about 85. What is the approximate measure of the vertex angle of the triangle?
*January 17, 2012*

**Chemistry**

You can also use d=PM/RT. Density is mass/volume. Plug it in and solve for M.
*January 16, 2012*

**Science**

I put Individuals of the same kind living in the same environment make up a population. All the populations of organisma living together in an environment make up a community. Is that correct?
*January 12, 2012*

**Science**

In my book it says Individuals of the same kind living in the same evnironment make up a population. All the grasshoppers in a field are the grasshopper population. All the populations of organisms living together in an environment make up a community What is the relationship ...
*January 12, 2012*

**Science**

It's not C, right?
*January 12, 2012*

**Science**

Nonliving things affect the organisms living in an ecosystem include weather,landforms,and?- A. habitat B. niche C. soil D. population I think its B
*January 12, 2012*

**Science**

I put Individuals of the same kind living in the same environment make up a population. All the populations of organisma living together in an environment make up a community. Is that correct?
*January 12, 2012*

**Science**

In my book it says Individuals of the same kind living in the same evnironment make up a population. All the grasshoppers in a field are the grasshopper population. All the populations of organisms living together in an environment make up a community What is the relationship ...
*January 12, 2012*

**physics**

When an airplane is in level flight, its weight is balanced by a verticallift, which is a force exerted by the air. How large is the lift on an airplane in such flight if the mass ofthe airplane is 1.20 x 10 cubed kg.?
*January 12, 2012*

**Science**

The journey of a cheese sandwich - how do you explain how cells use food using the big idea of partilces?????!!!!! HELP!!!! i hate these stupid assessments!!!!
*January 11, 2012*

**physics**

A 0.18 kg ball is placed in a shallow wedge with an opening angle of 110° For each contact point between the wedge and the ball, determine the force exerted on the ball. Assume the system is frictionless.
*January 9, 2012*

**History**

Is there any other similarities?
*January 9, 2012*

**History**

What do all of these former Presidents have in common? Abraham Lincoln,John F. Kennedy,James Garfield,and Franklin Roosevelt
*January 9, 2012*

**Reading**

I cant find any other details to replace number 5.
*January 5, 2012*

**Reading**

I meant to put on number 2 minerals not materials. Would that still be wrong?
*January 5, 2012*

**Reading**

Is this correct?
*January 5, 2012*

**Reading**

When you're scribbling a note with a pencil, do you ever wonder what this handy tool is made from? To get right to the point, a pencil is made of a number of materials. The inside is made of graphite that is reinforced with clay. Its wooden outside comes from cedar trees. ...
*January 5, 2012*

**Reading**

Icebergs can be slippery slopes for ships at sea. An iceberg can be dangerous to ships because more than 3/4 of it is under the water. Most of it isnt visible. Icebergs are found in the cold seas near the North and South Poles. The wind and currents move them through the water...
*January 5, 2012*

**physics**

A 80 kg man weighs 784 N on the Earth's surface. How far above the surface of the Earth would he have to go to "lose" 15% of his body weight?
*December 19, 2011*

**science**

laboratory connects a 16§Ù resistor, 23§Ù resistor, and a 34§Ù resistor in series and then comes the arrangement to a 36V dc source. How much current is in the circuit?
*December 17, 2011*

**science**

what are the forces on two charges of +0.44c and +2.4c, if they are separated bu=y a distance of 3.16cm? repel or attract each other?
*December 16, 2011*

**Chemistry**

Oops the charges in the equation got messed up so instead: MnO4- + 5Fe2+ + 8H+ -> 5Fe3+ + 4H2O
*December 15, 2011*

**Chemistry**

I had tremendous problems with this question as well, and since I now have the answer, I'll spread the love. First, you figure out how many moles of KMnO4 is used for both titrations using the equation ---- M=(mol)/(L) ---- (M=Molarity) Doing this, you would get the first ...
*December 15, 2011*

**math**

That question can't really be answered unless we can see the string
*December 13, 2011*

**5th grade math**

seven trillion six hundred fifty four billion three hundred twenty one million one hundred fifty eight thousand nine hundred six
*December 12, 2011*

**5th grade math**

Figure out what each place value the numbers are in
*December 12, 2011*

**biology**

A dominant gene V in humans causes certain areas of the skin to become depigmented, a condition called "vitiligo." Albinism is the complete lack of pigment production and is produced by the recessive genotype aa. The albino locus is epistatic to the vitiligo locus. ...
*December 12, 2011*

**statistics**

for a certain psychiatric evaluation z scores above 2.18 and below -2.33 are considered abnormal. what is the probability that a person evaluated by this will be considered normal?
*December 11, 2011*

**science**

place in order of increaseing nonmettalic character: Se, Po,and O. Can you explain how to do this?
*December 11, 2011*

**SCIENCE**

ORDER OF INCREASING ATOMIC SIZE: Cs, Li, and Rb
*December 11, 2011*

**calculus II**

Using integration by substitution. find the exact value of integral from [0,9/16] sqrt(1 - sqrt(x))/(sqrt(x))
*December 10, 2011*

**Top Schools**

Do what you want. Cause high school gets you into a college you want It depends on what you want to be when you grow up
*December 9, 2011*

**physics**

Calculate the difference between the magnitude of the gravitational force and the magnitude of the normal force exerted on a 100 kg object at the equator. Which of the two forces is equal in magnitude to the weight of the object?
*December 5, 2011*

**precalc**

Determine whether the sequence is geometric or arithmetic. Then give the general formula for the nth term of the sequence. 6.1, 6.9, 7.7, 8.5, 9.3,... I think it is Geometric, but i don't know how to find the formula
*December 5, 2011*

**math**

Is f(x)=4x/x-1 in factored form
*December 4, 2011*

**precalc**

Use Sigma Notation to write the sum [10-(1/10)^2]+[10-(2/10)^2]+[10-(3/10)^2]+[10-(4/10)^2]
*December 4, 2011*

**3rd grade math**

How can you use mental math to multiply 800 x 5?
*November 29, 2011*

**3rd grade math**

Marcia said that if she estimates 73 x7, the product will be less than the exact answer. Is she correct? Explain.
*November 29, 2011*

**statistics**

4. Assume you are just planning this survey and want to know how many individuals you have to randomly select to be part of the sample. Assume that the purpose of the study is to calculate a 95% confidence interval for proportion of the adult population who favor lowering the ...
*November 29, 2011*

**Economics**

D. (i), (ii), (iii), and (iv)
*November 29, 2011*

**precalc/trig**

Find the trigonometric form of the number. (Round any angles to two decimal places.) −8 − i
*November 29, 2011*