Thursday

September 3, 2015
Number of results: 84,547

**PHYSICS **

1. Why is an electric field considered to be a vector quantity? 2. Draw the electric field around an electric dipole of +1 µC and -1 µC 3. How many electrons have been removed from a positively charged object if it has a charge of 1.5 x 1011 C? 4. A particle with a charge - 1....
*December 21, 2012 by Hayden*

**physics**

a 51.0 kg uniform square sign, of edge L = 2.00 m, is hung from a horizontal rod of length dh = 3.00 m and negligible mass. A cable is attached to the end of the rod and to a point on the wall at distance dv = 4.00 m above the point where the rod is hinged to the wall.
*December 15, 2008 by help*

**PHYSICS HELP**

A pulley of mass mp , radius R , and moment of inertia about its center of mass Ic , is attached to the edge of a table. An inextensible string of negligible mass is wrapped around the pulley and attached on one end to block 1 that hangs over the edge of the table. The other ...
*November 17, 2013 by Anonymous*

**Physics**

A pulley of mass mp , radius R , and moment of inertia about its center of mass Ic , is attached to the edge of a table. An inextensible string of negligible mass is wrapped around the pulley and attached on one end to block 1 that hangs over the edge of the table. The other ...
*November 24, 2013 by Chelsea*

**Physics**

Find the angular velocity of a clock's second hand and the linear speed and linear acceleration of a point on the second hand 1.96 cm from the rotation axis.
*March 26, 2012 by Alex*

**Physics**

Find the angular velocity of a clock's second hand and the linear speed and linear acceleration of a point on the second hand 1.96 cm from the rotation axis.
*March 26, 2012 by Alex*

**Physics**

Find the angular velocity of a clock's second hand and the linear speed and linear acceleration of a point on the second hand 7.54 cm from the rotation axis.
*October 21, 2012 by Pat*

**Chemistry**

Many metals react with oxygen gas to form the metal oxide. For example calcium reacts: 2Ca(s) + O2(g)--> 2CaO(s) Calculate the mass of calcium prepared from 4,20g of Ca and 2.80g of O2. (a) How many moles of CaO can form from the given mass of Ca? (b) How many moles of CaO ...
*September 28, 2009 by Courtney*

**Chemistry**

Many metals react with oxygen gas to form the metal oxide. For example calcium reacts: 2Ca(s) + O2(g)--> 2CaO(s) Calculate the mass of calcium prepared from 4,20g of Ca and 2.80g of O2. (a) How many moles of CaO can form from the given mass of Ca? (b) How many moles of CaO ...
*September 29, 2009 by Courtney*

**Calculus**

The equation 10(x-1)(x-2)(x-3) = 1 has three real solutions a<b<c where a = , b = , and c = . Enter your answers with at least six correct digits beyond the decimal point. Hint: Ask what the solutions are if the right hand side is 0 instead of 1, and use Newton's Method.
*July 17, 2013 by J*

**Physics Urgent**

A 3.2 kg block is hanging stationary from the end of a vertical spring that is attached to the ceiling. The elastic potential energy of this spring/mass sytem is 2.2 J. What is the elastic potential energy of the system when the 3.2 kg block is replaced by a 5.6 kg block? For ...
*April 24, 2007 by Papito*

**physics**

Which direction will the support force by the wall point when the force diagram is drawn? The book is held motionless against a wall by yout hand. (Up, down, legt or right?)
*July 19, 2012 by dominique *

**Uni Math**

Simplify and state the domain: x'2 +1 . x'2 - 9 x'2 + 2x – 3 x'2 – 2x -3
*September 15, 2011 by Melanie*

**PreCalc**

Consider the tip of each hand of a clock. Find the linear velocity in millimeters per second for each hand. a. second hand which is 30 millimeters. b. minute hand which is 27 millimeters long. c. hour hand which is 18 millimeters long. Please tell me how you got the answer. ...
*November 18, 2007 by Joe*

**Physics**

An object has a weight of 0.852 N. It is suspended from a scale, which reads 0.749 N when the piece is submerged in water. What is the volume of the piece of metal?
*January 28, 2012 by Robb*

**physics**

want to bring a weight of 1 kg suspended at a height of 5 feet, slowly down so that it takes 1 min to reach down.how do i make this working
*November 24, 2013 by susan*

**Science**

What do all the words in the left hand cloumn have in common that is not shared by any of the qords in the right column? Thanks i hope you could help!! plus this too, i forgot to type it in ramp hammer screw faucet chisel axle doorstop hinge With only a brief examination, I ...
*April 8, 2007 by Danielle*

**Physics**

What is the weight of an object whose mass is 50 slugs? What is the mass of an object whose weight is 50 lbs.? Please indicate formula used.
*February 2, 2012 by Maria Ellah*

**Physics**

A roller-coaster car speeds down a hill past point A and then rolls up a hill past point B. The car has a speed of 16.1 m/s at point A. The acceleration of gravity is 9.81 m/s^2. Radius of Circle A is 9.98 m. Radius of Circle B is 15.5 m. a) If at point A the track exerts a ...
*November 13, 2010 by Jaylee*

**Physics**

Hi! Would one of you please check my work? Thanks! ( I used significant digits, by the way) A student throws a 5.00 kg steel shot directly upwards so that it leaves his hand when it is 2.00 m above the ground. If its velocity is 0.15 m/s when it leaves his hand, calculate: 1....
*December 29, 2014 by Lucina*

**PHYSICS **

A 5450-m^3 blimp circles Fenway Park duing the World Series, suspended in the earth's 1.21-kg/m^3 atmosphere. The density of the helium in the blimp is 0.178 kg/m^3. A) What is the buoyant force that suspends the blimp in the air? B) How does this buotant force compare to the ...
*April 2, 2012 by HELP PLEASE*

**physics**

A block of mass 0.74 kg is suspended by a string which is wrapped so that it is at a radius of 0.060 m from the center of a pulley. The moment of inertia of the pulley is 0.0061 kg·m2. There is friction as the pulley turns. The block starts from rest, and its speed after it ...
*February 11, 2014 by John*

**physics**

A block of mass 0.74 kg is suspended by a string which is wrapped so that it is at a radius of 0.060 m from the center of a pulley. The moment of inertia of the pulley is 0.0061 kg·m2. There is friction as the pulley turns. The block starts from rest, and its speed after it ...
*February 12, 2014 by Danny*

**Help - physics**

A block of mass 0.74 kg is suspended by a string which is wrapped so that it is at a radius of 0.060 m from the center of a pulley. The moment of inertia of the pulley is 0.0061 kg·m2. There is friction as the pulley turns. The block starts from rest, and its speed after it ...
*February 12, 2014 by Danny*

**Physics**

A glider of length 10.1 cm moves on an air track with constant acceleration. A time interval of 0.732 s elapses between the moment when its front end passes a fixed point circled A along the track and the moment when its back end passes this point. Next, a time interval of 1....
*September 16, 2014 by Karen*

**Physics**

A glider of length 10.1 cm moves on an air track with constant acceleration. A time interval of 0.732 s elapses between the moment when its front end passes a fixed point circled A along the track and the moment when its back end passes this point. Next, a time interval of 1....
*September 16, 2014 by Heather*

**Physics**

A thin insulating thread of length L is attached to a point on the perimeter of a thin disk. Disk is has radius R< L and is charged with a uniform surface density, σ>0. At the end of the thread there is a small ball mass m and charge q>0. The mass happens to be ...
*February 6, 2010 by Sandhya*

**physics**

Bar AB has length L, constant thickness d, and a width that tapers linearly from 3d at its fixed end (A) to d at its free end (B; see the figure below). The bar is homogeneous with mass density ρ and Young's modulus E. When hung vertically as shown in the figure, the bar ...
*June 23, 2014 by Donkey*

**Math**

A weight lifter is raising a barbell of mass 120kg. He does this in two stages. At the end of the first stage he holds the barbell steady at shoulder height. What upward force is each arm exerting?
*October 25, 2013 by Hussain *

**chemistry**

1) The color of bromocresol green indicator is??? when pH < 4, green when pH 4- 5.3 and ???? in pH > 5.3. 2)(A) A student performed the freezing point depression experiment according to directions but mistakenly recorded the mass of lauric acid as 8.300 g instead of 8....
*April 5, 2008 by chris*

**Physics**

Realizing that she often doesn't have her students' full attention during class, a professor devises an elaborate device on which to stand while she lectures. The pulley is placed so that the string makes a 45.0-degree angle with the beam. The beam is uniform, 5.00 meters long...
*January 5, 2012 by Daniel*

**Pysics**

Realizing that she often doesn't have her students' full attention during class, a professor devises an elaborate device on which to stand while she lectures. The pulley is placed so that the string makes a 45.0-degree angle with the beam. The beam is uniform, 5.00 meters long...
*January 5, 2012 by Daniel*

**Physics Classical Mechanics**

A pulley of mass mp , radius R , and moment of inertia about its center of mass Ic , is attached to the edge of a table. An inextensible string of negligible mass is wrapped around the pulley and attached on one end to block 1 that hangs over the edge of the table. The other ...
*November 14, 2013 by Anonymous*

**physics**

A uniform rigid pole of length L and mass M is to be supported from a vertical wall in a horizontal position, as shown in the figure. The pole is not attached directly to the wall, so the coefficient of static friction, μs, between the wall and the pole provides the only ...
*February 27, 2012 by rey*

**physics**

A uniform rigid pole of length L and mass M is to be supported from a vertical wall in a horizontal position, as shown in the figure. The pole is not attached directly to the wall, so the coefficient of static friction, μs,between the wall and the pole provides the only ...
*February 28, 2012 by need help*

**physics**

A uniform rigid pole of length L and mass M is to be supported from a vertical wall in a horizontal position, as shown in the figure. The pole is not attached directly to the wall, so the coefficient of static friction, μs,between the wall and the pole provides the only ...
*February 28, 2012 by Anonymous*

**Physics**

A uniform rigid pole of length L and mass M is to be supported from a vertical wall in a horizontal position, as shown in the figure. The pole is not attached directly to the wall, so the coefficient of static friction, μs,between the wall and the pole provides the only ...
*June 21, 2012 by James*

**Physics**

A plank 2.00 cm thick and 15.0 cm wide is firmly attached to the railing of a ship by clamps so that the rest of the board extends 2.00 m horizontally over the sea below. A man of mass 80.0 kg is forced to stand on the very end. IF the end of the board drops by 5.00cm because ...
*November 17, 2010 by Amber*

**Physics**

A plank 2.00 cm thick and 15.0 cm wide is firmly attached to the railing of a ship by clamps so that the rest of the board extends 2.00 m horizontally over the sea below. A man of mass 80.0 kg is forced to stand on the very end. IF the end of the board drops by 5.00cm because ...
*November 17, 2010 by Amber*

**maths PLEASE HELP**

A mixture contains two chemicals, A and B, with masses mA and mB. The total mass of the mixture, m, remains constant. B is converted into A at a rate that is inversely proportional to the mass of A and directly proportional to the square of the mass of B in the mixture at any ...
*March 9, 2010 by jessie*

**Calculus need help badllyyy!**

Use the expressions for left and right sums and the table below. right-hand sum = summation (n above and i =1 on the bottom) f(ti) * change in t = f(t1) * change in t + f(t2) * change in t + .... + f (tn) * change in t left-hand sum = summation (n above and i = 0 on the bottom...
*March 13, 2012 by Zoe*

**chem**

why is the ring of ammonium chloride closer to the hydrochloric acid end in the ring of gases experiment? i can say is that NH4Cl has greater amount of molecular weight than ammonium. is it right. pls help
*October 27, 2012 by Draden*

**Science**

It is found that 24.68 mL of 0.1165 NaOH is needed to titrate 0.2931 g of an unknown acid to the phenolphthalein end point. What is the equivalent mass of the acid? equivalent mass = grams acid/moles H+
*February 5, 2009 by Mini*

**Physics **

An iron block of the mass 1 kg is suspended on a spring of the spring constant 140 N/m, and merged into a vessel with 8 liters of water. The mass is displaced by 10 cm from its equilibrium position, and released. How much energy in J has been dissipated by the time the mass ...
*December 3, 2010 by HelpPlease*

**science**

A 4.50 g mass resting on a horizontal, frictionless surface is attached to one end of a spring; the other end of the spring is fixed to a wall. It takes 3.6J of work to compress the spring by 13.0 cm. If the spring is compressed, and the mass is released from rest. find a) the...
*February 5, 2015 by Peaches*

**MATH**

Solve by finding y and graph using the slope and y-intercept: 3x-y=1 x-y=3 3x-8=y Use the point-slope form of an equation to write the following in slope intercept form: m= 3 point: (4,2) m= 3/8 point: (3,5)
*May 12, 2012 by Please Please Help*

**Physics**

Hello, I posted this a bit ago, but am not sure the suggested solution was correct. Two physical pendulums (not simple pendulums) are made from meter sticks that are suspended from the ceiling at one end. The sticks are uniform and are identical in all respects, except that ...
*November 7, 2011 by Anonymous*

**Physics**

Suppose a crate of mass 2.8 kg is placed on the plank in the figure below at a distance 5.1 m from the left end. Find the forces exerted by the two supports on the plank. (The mass of the plank is 12.0 kg.) Left Support N Right Support N The plank set on two pivots one at 3.0m...
*March 6, 2011 by lala*

**college physics**

a 1.0 N-weight is hanging at rest as shown. In each case, write in the magnitude of the unknown force. a) chain with a weight of 2.5 N has a 1.0 N hanging weight b) chain with a weight of .5 N has a 1.0 N hanging weight c) stretched elastic band with negligible weight has a 1....
*March 8, 2012 by Amber*

**Physics**

An object has a weight of 0.838 N. It is suspended from a scale, which reads 0.705 N when the piece is submerged in water. What are the volume and density of the piece of metal?
*January 27, 2012 by Tor*

**Physics**

A 0.50-kg mass at the end of a spring vibrates 3.0 times per second with an amplitude of 0.15 m. Determine (a) the velocity when it passes the equilibrium point, (b) the velocity when it is 0.10 m from equilibrium, (c) the total energy of the system, and (d) the equation ...
*May 28, 2010 by Amber*

**Physics**

A .6-kg mass at the end of a spring vibrates 3.0 times per second with an amplitude of .13 m. Determine a.) the velocity when it passes the equilibrium point, b.) the velocity when it is .1 m from equilibrium. c.) the total energy of the system, and d.) the equation describing...
*July 17, 2010 by Stephanie*

**physics**

A uniform rod 30cm long is pivoted at it's center. A 40N weight is hung 5cm from the left end. where must the 50N weight be hung to maintain equilibrium?
*May 21, 2014 by fatimah*

**physics 8b**

A piece of wire with mass per unit length 88 g/m runs horizontally at right angles to a horizontal magnetic field. A 6.5A current in the wire results in its being suspended against gravity. What is the magnetic field strength? Express your answer using two significant figures...
*September 16, 2011 by help*

**8th grade science**

answer yes or no to weight, velocity,speed,& mass. 2 identical planes taveling @ 300 km/hr in opposite directions both have the same: weight-yes, velocity-no, speed-yes, mass-yes. velocity is a no, correct?
*February 20, 2011 by Roy S.*

**Chemistry**

I wanted to calculate the average equivalent weight of an unknown acid for an acid-base titration experiment. The mass of the unknown that I had to obtain is 0.2 g and the equivalents of the acid is .001046 L x N. But is this equation right? Does the equivalent mass equal to ...
*March 5, 2012 by Priscilla*

**vibration**

a uniform cantilever beam of the total mass ml has a concentrated mass M at its free end. determine the effective mass of the beam to be added to M assuming the deflection to be that of a massless beam with a concentrated force at the end, and write the equation for its ...
*May 17, 2011 by matt*

**physics**

Two 0.09 pith balls are suspended from the same point by threads 40 long. (Pith is a light insulating material once used to make helmets worn in tropical climates.) When the balls are given equal charges, they come to rest 19 apart. What is the magnitude of the charge on each ...
*January 23, 2010 by Lanise*

**physics**

Two 0.09 pith balls are suspended from the same point by threads 40 long. (Pith is a light insulating material once used to make helmets worn in tropical climates.) When the balls are given equal charges, they come to rest 19 cm apart What is the magnitude of the charge on ...
*January 23, 2010 by Lanise*

**Physics HELP!**

A simple pendulum consists of a small object of mass 7.40 kg hanging at the end of a 2.10 m long light string that is connected to a pivot point. (a) Calculate the magnitude of the torque (due to the force of gravity) about this pivot point when the string makes a 3.00° angle ...
*November 7, 2012 by Brad*

**physics**

A simple pendulum consists of a small object of mass 3.20 kg hanging at the end of a 3.70 m long light string that is connected to a pivot point. (a) Calculate the magnitude of the torque (due to the force of gravity) about this pivot point when the string makes a 7.00° angle ...
*November 11, 2012 by Anonymous*

**Chemistry**

Individuals living near copper mines sometimes earn extra money by suspending iron objects in the mine wastewater. Based on your experimentation, explain why the iron objects would be suspended in the wastewater.
*October 31, 2013 by Anonymous*

**physics**

A grandfather clock uses a physical pendulum to keep time. The pendulum consists of a uniform thin rod of mass M = 7.01 kg and length L = 0.15 m that is pivoted freely about one end, with a solid sphere of the same mass, 7.01 kg, and a radius of L/2 centered about the free end...
*February 19, 2012 by janny*

**Physics **

a 1.0 N-weight is hanging at rest as shown. In each case, write in the magnitude of the unknown force. a) chain with a weight of 2.5 N has a 1.0 N hanging weight b) chain with a weight of .5 N has a 1.0 N hanging weight c) stretched elastic band with negligible weight has a 1....
*March 11, 2012 by Brandon *

**physics**

A mass of 8.10 kg is suspended from a 1.69 m long string. It revolves in a horizontal circle as shown in the figure. The tangential speed of the mass is 2.92 m/s. Calculate the angle between the string and the vertical.
*February 17, 2011 by Sarah*

**physics**

a bullet of mass 10gm travels horizentaly with v=100m/sec and it is absorted by wooden block of mass 990gm.suspended verticle height through which the block...?
*September 18, 2013 by sajal*

**Chemistry(Please check)**

1) The molecular mass of a substance was determined by the freezing point depression technique. The minimum data required for the determination are: a) delta T and Kf only b) delta T, Kf, and mass of solute c) delta T, Kf, mass of solute, and mass of solvent d) delta T, Kf, ...
*February 10, 2012 by Hannah*

**Chemistry(Please check)**

1) The molecular mass of a substance was determined by the freezing point depression technique. The minimum data required for the determination are: a) delta T and Kf only b) delta T, Kf, and mass of solute c) delta T, Kf, mass of solute, and mass of solvent d) delta T, Kf, ...
*February 11, 2012 by Hannah*

**Physics**

Suppose now that the air carts below are both moving to the right initially. The cart to the left has a mass m1 and an initial speed v0; the cart to the right has an initial speed v0/2. If the center of mass of this system moves to the right with a speed 6/7 v0, what is the ...
*April 27, 2010 by Kelly*

**math**

the straight L has gradient 3 and passes through the point A(-6,4). a) find an equation for L in the form y=mx+c b) straight line R has the equation in the form of -7y+x+14=0. Given that R crosses the y-axis at the point B and intersects L at the point C, find the coordinates ...
*February 24, 2012 by aminath*

**physics**

Two identical small insulating balls are suspended by separate 0.17 m threads that are attached to a common point on the ceiling. Each ball has a mass of 7.40 10-4 kg. Initially the balls are uncharged and hang straight down. They are then given identical positive charges and...
*February 27, 2014 by Jen*

**AP Calc. AB**

Create two different functions for which the left-hand limit at zero is 0 and for which the right hand limit at zero is 8
*August 31, 2014 by Jacke *

**math**

i have more than one question so if u no any of the answers please tell me 1.) write the point-slope form of the equation of the line with slope -2 passing through the point ( -5, -9). 2.) write the point-slope form of an equation of the line through the points at ( -9, -9) ...
*May 17, 2010 by becca*

**physics**

A woman has a mass of 42.9 kg. What is her weight on earth? and what is her weight on the moon, where g=1.17 m/s2
*October 26, 2010 by Jason*

**Science**

What is the mass if a bag if its weight is 9.5N? What is its weight when it is brought to the moon?
*June 16, 2015 by Jeric*

**Science check answer quick!**

I really do not understand Number 7 Which of these does Newton's law of universal gravitation imply? (Points : 1) The force of gravity between two objects is inversely proportional to the product of the two masses. <-- Earth's gravity acts on people inside a space station ...
*January 7, 2014 by Gianna*

**math**

A=1/2h (b1 + b2) Solve for b1 A=1/2h (b1 + b2) Solve for b1 I assume this is A = (1/2)(h)(b1 + b2); i.e., the h is in the numerator and not the denominator Multiply both sides by 2. 2A = (2*1/2)h(b1 + b2). 2*1/2 on the right side is 1. 2A = h(b1 + b2) expand the right side. 2A...
*August 15, 2006 by ryan*

**Repost- Calculus; someone please help**

Please help out. Thank you. A right triangle has one leg on the x-axis. The vertex at the right end of that leg is at the point (3,0). The other vertex touches the graph os y=e^x. the entire triangle is to lie in the first quadrant. Find the maximum area of this triangle....
*February 9, 2011 by Amanda E.*

**PLEASE HELP WITH MATH**

PLEASE HELP WITH MATH ANY HELP OR ANSWER IS APPRECIATED! 1. If the hands on a round clock moved counter-clockwise, to what number would the minute hand point 20 minutes before the hour hand pointed to the 3?
*August 12, 2014 by Menepsimo*

**algebra**

the body mass index is given by the formula, or model, I=700w/h(2), where w= weight and h = height in inches. Jerome is 76 inches tall. what weight will keep his body mass index between 25 and 33 Jeromes body mass index will fa;ll between 25 and 33 for the set of weights such ...
*March 28, 2010 by ron*

**electricity**

to use your left hand to determine the direction of the voltage developed in a moving conductor in a stationary magnetic field, you must point your? A) thumb in the direction of the magnetic flux. B)thumb in the direction of the electromagnetic force. C)forefinger in the ...
*August 23, 2005 by angela*

**Physics**

Consider a rod plus disc system. The rod has a total length L =1.30 m, while the disc has a radius of R = L/2. The pivot is at P where the distance between P and the end of the rod is L/4. Point O is at the center of the disc, and the distance between O and P is 0.975 m. The ...
*October 19, 2014 by Misaki*

**Calculus**

The height (in feet) at time t (in seconds) of a small weight oscillating at the end of a spring is given below. h(t) = 0.2 cos(2t) (a) Calculate the weight's average velocity over the time intervals [1, 2] and [5, 7].
*January 26, 2013 by Lindy*

**chemistry**

A 10 milliliter sample of HCl pickle is titrated with 0.2 N NaOH to a phenol-phthalein end point and it is found that 6.5 milliliters are used. What is the concentration of HCl in the Pickle in grams per liter? In weight Percent?
*February 3, 2012 by bob*

**Chemistry**

Why are the properties of alloys gnerally superior to their constituent components? In most cases, not all, mixing metals forms eutectics (sometimes called eutectic mixtures). These eutectic mixtures are the combination of the elements that form the lowest melting point of the...
*November 29, 2006 by Bryan*

**Math problem**

-A clock is divided equally into 60 units. Each unit forms an angle of 6^0.The hour hand moves 1 of these units for every 12 units that the minute hand moves. it move 2 of these units for every 24 units for the minute hand,ete.At 6 o'clock the hour hand and the minute hand are...
*February 12, 2013 by Mike*

**physics**

A bob of mass = 0.250 is suspended from a fixed point with a massless string of length = 23.0 . You will investigate the motion in which the string traces a conical surface with half-angle = 25.0. What tangential speed must the bob have so that it moves in a horizontal circle ...
*October 3, 2010 by bryan*

**Physics**

You throw a glob of putty straight up toward the ceiling. Which is 3.60 m above the point where the putty leaves your hand. The initial speed of the putty leaves as it leaves your hand is 9.50m/s.<br> (A) what is the speed of the putty just before it strikes the ceiling...
*August 24, 2015 by Dave Ang*

**physics**

A small girl of weight 150N is placed on the centre of the plank. She then walks to the right and goes past trestle Q. When the plank is on the point of tipping up, where will the fulcrum be?
*October 20, 2014 by Donte*

**Physics**

Two physical pendulums (not simple pendulums) are made from meter sticks that are suspended from the ceiling at one end. The sticks are uniform and are identical in all respects, except that one is made of wood (mass=0.34 kg) and the other of metal (mass=0.63 kg) They are set ...
*November 7, 2011 by Anonymous*

**physics**

A person holds a 1.42N baseball in his hand, a distance of 34.0cm from the elbow joint, as shown in the figure . The biceps, attached at a distance of 2.75cm from the elbow, exerts an upward force of 12.6N on the forearm. Consider the forearm and hand to be a uniform rod with ...
*October 29, 2011 by B*

**Math help quickly**

Use the expressions for left and right sums and the table below. right-hand sum = summation (n above and i =1 on the bottom) f(ti) * change in t = f(t1) * change in t + f(t2) * change in t + .... + f (tn) * change in t left-hand sum = summation (n above and i = 0 on the bottom...
*March 13, 2012 by Zoe*

**Physics **

The mass of an astronaut is 72kg. (a) what is his weight on earth ( taking g to be 10N/kg) ? (b) if the astronaut is on the moon's surface where the acceleration due to gravity is one-sixth on the earth , calculate (I) the mass (ii) the weight of the astronaut Thanks for ...
*June 2, 2011 by Lina*

**Physics**

A 50 kg box rests on a smooth frictionless table. Connected to the box is a light string passing through a pulley at the end of the table. Suspended on rhe other end of the string is a 20 kg box. Find a) acceleration of the system, b) the tension in the string c) the ...
*August 19, 2014 by JOSH*

**conseptual physics**

if you hold one end of a metal nail against a piece of ice, the end in your hand soon becomes cold. does cold flow from the ice to your and? why?
*May 3, 2011 by jessica*

**Chemistry**

The normal freezing point of cyclohexane is 6.55 C. When 0.458 g of benzophenone is dissolved in 15.0 g of cyclohexane, the freezing point is found to be 3.19 C. What is the experimental molar mass of benzophenone? (Kf cyclohexane = 20.0 C m^-1). A) 182 B) 866 C) 397 D) 191 (...
*November 9, 2012 by Ania *

**Physics**

A hiker who weighs 834N, is strolling through the woods and crosses a small horizontal bridge. The bridge is uniform, weighs 3520N, and rests on two concrete supports at each end. He stops one-fifth of the way along the bridge. What is the magnitude of the force that a ...
*November 12, 2012 by sarah*

**physics**

A simple pendulum consists of a small object of mass 1.2 kg hanging at the end of a 2.07 m long light string that is connected to a pivot point. Calculate the magnitude of the torque (due to the force of gravity) about this pivot point when the string makes an angle of 6.59 ...
*March 26, 2014 by Anonymous*

**Physics**

A pendulum is composed of a mass m suspended from the ceiling by a massless string of length L. If the mass is pulled back so that it is raised an amount L/4 and then released, what is the tension on the string at the bottom of the swing? A.3 mg B.4 mg C.2 mg D.5/2 mg E.3/2 mg...
*May 4, 2012 by Chris*

**physics**

A 15 kg mass, tied to the end of a 0.5 m long steel wire, is whirled in a vertical circle. The cross- section of the wire is 0.02 cm2. When the mass is at the bottom of the circle, its angular velocity is 2 rev s i. Find the elongation of the wire at this point.
*January 2, 2014 by badar*