# Posts by sandhya

Total # Posts: 246

**maths**

find the sum to 20 terms of an A.P. whose 4th term is 7 and 7th term is 13

**science**

6.023*x10^21 electrons are present n a given amount of ammonium (NH3).How much amount of hydrogen is required to produce the sample of ammonia

**Math**

$20000 amount to $ 24200 in two years under compound interest compounded annually

**English**

Rewrite the sentence without changing the meaning. It doesn't matter

**Chemistry**

Actually I figured out a, b, c, and d but I can't figure out e. What do you do if HCl is in excess?

**Chemistry**

A 10.0-mL solution of 0.300 M NH3 is titrated with a 0.100 M HCl solution. Calculate the pH after the following additions of the HCl solution: a) 0.00 mL b) 10.0 mL c) 20.0 mL c) 30.0 mL d) 40.0 mL **I know how to solve the problem but I keep getting answers that are exactly ...

**Chemistry**

Yes I can thank you so much Dr. Bob! I got an answer of 8.38 as a pH which seems to be right. Thanks again!

**Chemistry**

A solution is made by mixing 5.00 × 102 mL of 0.167 M NaOH with 5.00 × 102 mL of 0.100 M CH3COOH. Calculate the equilibrium concentrations of H+, CH3COOH, CH3COO−, OH−, and Na+.

**Psychologic**

2,3,4

**operating system**

what is the difference between deadlock and stravation

**Physics**

A 600-kg car is going around a curve with a radius of 120 m that is banked at an angle of 25.0° with a speed of 30.0 m/s.The coefficient of static friction between the car and the road is 0.300. What is the force exerted by friction on the car?

**english**

assignment on common man's crusade

**physics**

a ball rolls down a roof that makes an angle of 30 to horizontal.it rolls off the egde with a speed of 5.00m/s.distance to the ground from that point is 7.00m a)how long is the ball in the air b)how far from the base of the house does it land? c)what is its speed just before ...

**statistic**

The mean salary per day of all the 5000 employees who work in a company is 150 Rs. and the standard deviation is 15 Rs. Let be x bar is the mean salary per day for a random sample of certain employees selected from this company. Find the mean and standard deviation for sample ...

**ms. sue pls. help me urgent**

mistakes motivate me to become a good speaker

**Math**

1.Approximate sqrt3 by applying Newton's Method to the equation (x^2-3) = 0 2.The equation (x^3-x-2) = 0 has one real solution for 1<x<2.Approximate it by Newton's method.

**Math**

Express the number 25 as a sum of two nonnegative numbers whose product is as large as possible.

**physics-Electric & magnetic fields**

A proton traveling at 10^4 m/s in the positive x-direction, enters a region where there is uniform electric field of magnitude 10 v/m and a uniform magnetic field of magnitude 10^-2 T. The electric and magnetic fields are parallel and are in the z-direction. In the following ...

**physics**

A proton traveling at 10^4 m/s in the positive x-direction, enters a region where there is uniform electric field of magnitude 10 v/m and a uniform magnetic field of magnitude 10^-2 T. The electric and magnetic fields are parallel and are in the z-direction. In the following ...

**physics**

A proton traveling at 10^4 m/s in the positive x-direction, enters a region where there is uniform electric field of magnitude 10 v/m and a uniform magnetic field of magnitude 10^-2 T. The electric and magnetic fields are parallel and are in the z-direction. In the following ...

**physics**

The change in electrostatic potential energy at a point when an electron is brought from infinity to that point is deltaE.What is the change in electrostatic potential energy if the electron is moved through a distance d from this point?

**physics-Moment of Inertia**

Two equal masses m are place at positions r1= (L, 2L, 3L) and r2= (3L, L ,2L). Calculate the moments of inertia Ix, Iy, Iz of the system with respect to the x, y, and z axes.

**physics**

Two equal masses m are place at positions r©û= (L, 2L, 3L) and r©ü= (3L, L ,2L). Calculate the moments of inertia Ix, Iy, Iz of the system with respect to the x, y, and z axes.

**physics**

1.Three masses, m1, m2, and m3, are lying on a plane without friction and are connected by a string. A force F is applied to the mass m1 so that the whole system accelerates along a straight line. What is the tension of the string T between the masses m1 and m2? What is the ...

**physics**

1.A cylinder rolls without slipping on a horizontal plane and then up an incline. The linear speed of the cylinder at the beginning is v. What maximal height h will the cylinder reach? 2.Helicopter of mass M holds stationary in the air fires a missile of mass m<< M with ...

**Chemistry**

Wait, then why isn't the concentration of [H+] also considered to be zero since the value is so small?

**Math**

Sketch the graph of i) g(x) = sqrt(6x - x^2) ii)f(x) = (x^2 -2x - 3)/(x - 3)

**Math-Functions**

a) g(1) = (1 + 1)/1 = 2/1 = 2 b) g(0) =( 0 + 1)/0 = 1/0 = ¡Þ c) g(-1) = (-1 + 1)/-1 = 0/-1 = 0 d) g(x-1) = {(x ¨C 1) + 1}/(x ¨C 1) = x/(x ¨C 1)

**Math-Functions**

If g(x) = (x + 1)/x,find a) g(1) b) g(0) c) g(-1) d) g(x - 1)

**math-functions**

If y = x^2 + 5x - 9,for what values of x is y>5?

**physics**

What is the approximate energy emitted as blackbody radiation by a human being each second? What is the blackbody energy absorbed by a person in 1 s in a room? Why are the answers different?

**physics**

A snake is sunning itself on a rock. (a) If the snake is 0.3 m long, what is the approximate amount of radiation it absorbs from the sun in 10 minutes? (b) If no heat flows out of the snake via conduction or by evaporative cooling, how much does its temperature increase during...

**US HISTORY**

from fdr's first inaugral speech ,how did he attempt to win the support of the american people for his leadership during the economic crisis of the great depression

**us history**

from fdr's first inaugral speech ,how did he attempt to win the support of the american people for his leadership during the economic crisis of the great depression

**physics**

A 1520-N crate is to be held in place on a ramp that rises at 30.0° above the horizontal. The massless rope attached to the crate makes a 22.0° angle above the surface of the ramp. The coefficients of friction between the crate and the surface of the ramp are ìk...

**physics**

A charge is uniformly distributed over a linear section from 0<x<1 such that the charge density is 10epsilon. Find the potential and the electrical field across the region assuming that V(0)=0 and V(1) = 10.

**physics**

A particular amplifying device supplies electrons in a manner such that the current passing out of the device is given by I(t) = (Io)e^kt, where I(0) = Io = 2A.The current measured 12 seconds later is 3.4 A.Find (a)The charge Q that passes out of the device as a function of ...

**physics**

A 3640 lb roller coaster experiences a constant air-resistance force of 26 lb and a constant friction force of 20 lb. What initial velocity is required for the coaster to make it around the 0.57 mile track and coast to a stop at its starting location?

**physics**

Distance is pi(R) but displacement is only 2R ,the diameter of the semi-circle

**physics**

A 27 g bullet traveling at 297 m/s is fired into a 0.468 kg wooden block anchored to a 100 N/m spring. How far is the spring compressed

**physics**

A 27 g bullet traveling at 297 m/s is fired into a 0.468 kg wooden block anchored to a 100 N/m spring. How far is the spring compressed

**physics**

A large uniform block rests horizontally on two vertical supports(one support at the left end of the block and another at a distance from the other end) and has a weight hanging from its other end. The block has a mass of 100 kg and a length of 2 meters. If the hanging weight ...

**physics**

A large uniform "butcher block" rests on two supports(one support at the left end of the block) and has a weight hanging from its end. The block has a mass of 100 kg and a length of 2 meters. If the hanging weight is 59 newtons, what is the minimum value for L for ...

**physics**

A large uniform "butcher block" rests on two supports(one support at the left end of the block) and has a weight hanging from its end. The block has a mass of 100 kg and a length of 2 meters. If the hanging weight is 59 newtons, what is the minimum value for L for ...

**physics**

thanks for your timely help.

**physics**

A person using a ladder supported on vertical wall is 3/4 of the way up the ladder. If the person climbing the ladder has a weight of 980 newtons and the ladder is 4.89 meters long, how far from the wall can the base of the ladder be placed, and not slip? The coefficient of ...

**physics**

A person using a ladder supported on vertical wall is 3/4 of the way up the ladder. If the person climbing the ladder has a weight of 980 newtons and the ladder is 4.89 meters long, how far from the wall can the base of the ladder be placed, and not slip? The coefficient of ...

**physics**

A person using a ladder supported on vertical wall is 3/4 of the way up the ladder. If the person climbing the ladder has a weight of 980 newtons and the ladder is 4.89 meters long, how far from the wall can the base of the ladder be placed, and not slip? The coefficient of ...

**physics**

Thanks a lot

**physics**

A 1-kg mass hangs by a string from a disk with radius 5.1 cm which has a rotational inertia of 5 × 10-5 kg•m2. After it falls a distance of 1.4 meters, how fast is it going? What is the angular velocity of the disk?

**physics**

A rocket has an exhaust gas velocity of 2329 m/s and an expelled gas rate of 6761 kg/s. If it has a mass of 1.82 × 10^6 kg what is its initial acceleration ?

**physics**

The room that contains the refrigerator will be warmer than the other room

**physics**

Consider two identical rooms, one with a refrigerator in it and the other without one. If all the doors and windows are closed, will the room that contains the refrigerator be cooler or warmer than the other room? Why?

**physics**

Consider two closed systems A and B. System A contains 3000 kJ of thermal energy at 20°C, whereas system B contains 200 kJ of thermal energy at 50°C. Now the systems are brought into contact with each other. Determine the direction of any heat transfer between the two ...

**physics**

One kilogram of water vapor at 200 kPa fills one side of a partitioned chamber. The right side is twice the volume of the left and is initially evacuated. Determine the pressure of the water after the partition has been removed and enough heat has been transferred so that the ...

**physics**

One kilogram of water vapor at 200 kPa fills one side of a partitioned chamber. The right side is twice the volume of the left and is initially evacuated. Determine the pressure of the water after the partition has been removed and enough heat has been transferred so that the ...

**physics**

One kilogram of water vapor at 200 kPa fills one side of a partitioned chamber. The right side is twice the volume of the left and is initially evacuated. Determine the pressure of the water after the partition has been removed and enough heat has been transferred so that the ...

**physics**

Thanks for the timely help

**physics**

Two particles are created in a high-energy accelerator and move off in opposite directions. The speed of one particle, as measured in the laboratory, is 0.700 c , and the speed of each particle relative to the otheris 0.920 c . What is the speed of the second particle, as ...

**physics**

Thanks a lot

**physics**

The number of significant figures in 0.00150 is ....

**physics**

What is the relation between the average velocity in a given time interval and the instantaneous velocity in the interval?

**physics/math**

Thanks a lot for your help

**physics/math**

Does the formula Sum of internal angles of a polygon = (n - 2)x180 degrees, where n represents number of sides, work for polygons of intersecting sides? correction please 'intersecting' in the place of 'interacting'

**physics/math**

Does the formula Sum of internal angles of a polygon = (n - 2)x180 degrees, where n represents number of sides, work for polygons of interacting sides?

**physics**

Thanks a lot

**physics**

A one tonne moon obiter is to approach the moon and orbit through 270 degrees at an altitude of 100km. During this period its rockets are to be turned off. What is the required velocity of the obiter at the entry point to prevent the vehicle from crashing into the moon?

**physics**

A 50g ice cube is added to 110g of water in a 62g aluminum cup. The water and cup initially have a temperature of 23°C. Find the initial temperature of the ice cube such that all of the water is just turned to ice. Use the following specific heats: water = 4186 J/(kg•...

**physics**

1.A round wooden log of diameter 73cm floats with half of its radius above water. Determine the log’s density 2.An ideal gas doubles its volume in one of three different ways: at constant pressure, at constant temperature, and adiabatically. For each method, give an ...

**physics**

A 25 kg box slides, from rest, down a 9-m-long incline making an angle 15 degrees with the horizontal. The speed of the box when it reaches the bottom of the incline is 2.40 m/s. (a) What is the coefficient of kinetic friction between the box and the surface of the incline? (b...

**physics**

Noreen drops a big pumpkin from the top of a tall building and hears the splash on a trash can 4.50 seconds after she released it i.e. total time. How much a) time for the pumpkin to fall, b) the sound to rise and c) the height of the building?

**physics**

Imagine an airplane flying under a cloud during a thunderstorm.Do the passengers get electrocuted? Explain why or why not. Should the airplane's wheels be insulators or conductors? Explain why.

**physics**

Imagine an airplane flying under a cloud during a thunderstorm.Do the passengers get electrocuted? EXPLAIN WHY or WHY NOT. Should the airplane's wheels be insulators or conductors? EXPLAIN WHY.

**physics**

A double slit diffraction pattern is formed on a distant screen using mercury green light of wavelength 546.1 nm. Each slit has a width of 0.1 mm. The pattern shows that the 4th order interference maximum is missing. a) What is the separation of the slits? b) What is the ...

**physics**

A reflection grating is required which can resolve wavelengths as close as 0.002 nm in second order for the spectral region around 350 nm.The grating is to be installed in an instrument where light from the entrance slit is incident normal on the grating. If the manufacturer ...

**physics**

A baseball is thrown at 88 mi/h and with a spin rate of 1500 rev/min. If the distance between the pitcher’s point of release and the catcher’s glove is about 61 feet, estimate how many revolutions the ball makes between release and catch. Neglect any effects of ...

**physics**

A uniform 2.00-m-long stick is raised at an angle of 30° to the horizontal above a sheet of ice. The bottom end of the stick rests on the ice. The stick is released from rest. The bottom end of the stick remains in contact with the ice at all times. How far will the bottom...

**physics**

I am unable to visualize a rolling railroad car passing by a grain elevator

**physics**

A railroad car rolling along by itself is passing by a grain elevator, which is dumping grain into it at a constant rate. (a) Does momentum conservation imply that the railroad car should be slowing down as it passes the grain elevator? Assume that the track is frictionless ...

**maths**

c) An equilateral triangle of side 3 cm each is given, How many triangles can be made from this equilateral triangle of 1cm?

**physics**

1.An elastic cord is 5.0m long and 1.0cm in diameter and acts as a spring with spring constant 70 N/m, what is the young's modulus for this material? 2.A heavy uniform beam of mass 8000 kg and length 2.0m is suspended at one end by a nylon rope of diameter 2.5 cm and at ...

**physics**

1. If a steel rope and a nylon rope of equal lengths are to stretch by equal amounts when subjected to equal tensions, what must be the ratio of their distances? 2.A simple hand operated hydraulic press can generate a pressure of 6.0 X 10^9 N/m^2 . If the system is used to ...

**physics**

Calculate the magnetic field at the center of a wire square that consists of 120 loops and has sides of length 5 cm and carries a current of 0.7 A.

**Physics**

A 15 μA current starts flowing in a circuit with a 3.0 μF capacitor of area 40 cm^2 at t = 0 s.(a) How fast is the voltage across the capacitor plates changing at t = 0 s? (b) Use the result of (a) to calculate the following at t = 0 s.(i) dφB/dt in V.m/s (ii) ...

**physics**

Consider two small circular current loops. Suppose one loop is placed above the other (but not touching), with their areas oriented similarly. Do the loops repel, attract or have no effect when the currents are in the same direction? In the opposite direction?

**physics**

Consider a parallel-plate capacitor with charge density 7.5 10-7 C/m2 on the two plates and an electric field that points in the +z direction. What magnetic field is necessary to provide a velocity selector for 58 keV deuterons that move in the +y direction? A deuteron has a ...

**physics**

A wire of length 11 cm carries a current of 1.1 A. When the wire is placed so that the current passes through the wire along the positive x direction, the force on the wire due to an external magnetic field B is measured to be -(0.04 N)j. When the wire is moved so the current ...

**physics**

A 160 MeV proton, moving in the x-direction, enters a region in which there is a magnetic field. The proton experiences an acceleration of 5.5 X 10^12 m/s^2 in the y-direction. What can you say about the magnetic field?

**physics**

1.The earth is constantly bombarded by cosmic rays, which are charged particles from outer space. moving vertically Find the force on one such cosmic ray− a proton that is instantaneously downward at 5.04 107 m/s at a point outside the atmosphere over New York, where the...

**physics**

(1)A parallel-plate capacitor carrying charge q0 is modified by the insertion of a dielectric with κ = 4.3 between the plates. As a consequence, the energy stored in the capacitor quadruples. What will the charge be after the dielectric is inserted? (2)A metal sphere of ...

**physics**

If only external forces can cause the center of mass of a system of particles to accelerate, how can a car on level ground ever accelerate? We normally think of the car’s engine as supplying the force needed to accelerate the car, but is this true? Where does the external...

**physics**

Thank you very much

**physics**

Imagine yourself seated on a wheeled desk chair at your desk. Consider friction forces between the chair and the floor to be negligible. However, the friction forces between the desk and the floor are not negligible. When sitting at rest, you push horizontally against the desk...

**physics**

Thanks a lot

**physics**

If only a single nonzero force acts on an object, does the object accelerate relative to all inertial reference frames? Is it possible for such an object to have zero velocity in some inertial reference frame and not in another? If so, give a specific example.

**physics**

Here R = 0.20 m mV^2 /R = kQq/R^2 Am I right?

**physics**

A particle of charge Q is fixed at the origin of an xy coordinate system. At t = 0 a particle (m = 0.690 g, q = 4.75 µC) is located on the x axis at x = 20.0 cm, moving with a speed of 50.0 m/s in the positive y direction. For what value of Q will the moving particle ...

**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 ...

**Physics**

A soap bubble is given negative charge, what will happen it the radius and why?

**Physics**

Thanks