Yuni

This page lists questions and answers that were posted by visitors named Yuni.

Questions

The following questions were asked by visitors named Yuni.

potential difference=40v b2n plate A & B. find work done if q=+3C from a) B to A b) A to B *i already know the ans but i need the explanation for the formula. -this is my work a)w=-qv b)-120J =-3(-40) =120 J what i want to ask is: 1-why must we add - sign...

a liquid form of penicillin is sold in bulk at a price of $ 200 per unit.If the total cost for x unit is C(x)=500000+80x+0.003X^2 and the production capacity is at most 30000 at a specified timed, how many of the penicillin must be manufactured and sold i...

the volume of an cylindrical can with a radius r cm and height h cm is 128000 c^3, show that the surface area of the can is A=2(22/7)r^2 + 246000/r. Find the value for r to minimize the surface area. *i know what the quest. ask but i do not know how to ap...

A piece of wire of length 240 cm is bent into the shape of trapezium where the eqtn is = 13x+13x+y+y+24x. Find the value of x and y for which A is maximum, hence find the maximum area. a. express y in term of x b. show that the area A cm^2 enclosed by the...

what is the original color of Phenolphthalein solution? pink or colourless?

how to know from the experiment if the oxygen produced as a result of carbon fixation or electron transport? my experiment result show that average bubble/min for tap water is 4.7 while NaHCO3 is 1.8.

150 cm3 0.24 M naoh solution react with excess al(no3)3, calculate the mass of saodium aluminate produced. al(no3)3 + 4naoh -> naalo2 + 3 nano3 +2h20 i got 0.738g.. is my answer correct? if im wrong could u show me the calculation?

the atom of element A has 2 electrons in its highest energy level N. a)what is the special name given to elements in the same gp as A? i answered as alkali earth metal because the valence electron is 2. am i right?

rate=k[A2][B2]^2. by how much would the rate change if: i) [A2] is doubled? ii) [B2] is halved? *does the rate change equal with k?

prove cos(x+y) / cos(x-y) = (1-tan x tan y)/(1+tan x tan y)

if a & b are perpendicular vectors, show that a)(a+2b).(a-b)=|a|^2-2|b|^2 b)(a+b).(a-b)=|a|^2+|b|^2 *how to show it?just multiply it?if yes where does||come from? does||show that it should be a value?

are blood pressures have differences between genders?explain your answer. -from what i know, women have lower risk to get high blood pressure but for the range of normal blood pressure, i think there is no differences. pls correct me if i wrong and if im...

The reaction AB(aq)->A(g)+ B(g)is second order in AB and has a rate constant of 0.0282 M^{-1} s^{-1} at 25 Celsius. A reaction vessel initially contains 250 mL of 0.105 M AB which is allowed to react to form the gaseous product. The product is collected o...

the common metallic elements have been invetigated for their relative reactivities and have been arranged into what is called electromotive series. Explain the series in terms of choosing the suitable electrode in setting up an electrochemical series.

Salt dissolving in water is an example of a chemical change

Answers

The following answers were posted by visitors named Yuni.

can any1 plz answer this question.

im sorry but b4 this i already seacrh at the internet but i didn't found what i want. so i hope there will be another answer coming on.

i'm sorry. the electric field are from A to B. dear drwls,you didn't answer my question. i know about the concept but why the v is negative? or how can it be proven mathematically by the formula?.

is the answer 1392 s?