Recent content by ghostbuster25

I am revising for my A levels and I have noticed that a common question on the paper is to define RESISTIVITY. I have looked and looked but found no definitive description or a good definition. I know the formula but is it right to just say that "resistivity is directly proportional to a...

Just wondering if anyone can check over my answer for a question. Q) A 1.7kg object is swung on the end of a 0.6m string in a vertical circle. The object does one revolution every 1.1s. What is the tension in the string at the top of the circle? and the bottom? A) m=1.79kg r=0.6m...

just a check of my work please. I have to write an expression for the nth term of this geometric sequence. a1=100 a2=106 a3=112.36 I've worked out the ratio to be r=1.06 I am using the formula un=ar(n-1) so the expression i have come up with is un=100(1.06)(n-1) Is this correct? I have...

sorry i made a mistake in the question part, it is supposed to read u1=-1

Just a check of my work please, The topic is series and sequence, Question: The sequence u1, u2, u3,... where u1 is defined by u1=2 and Un+1 =un+4 Find the nth term, un, of the sequence. I got the answer, u1=-1 u2=-1+4= 3 u3= 3+4 = 7 So: un = 4(n-1)-1 This seems to work but not sure if it...

I'm pretty sure the lost volt is the resistance inside the battery. Once you work out the lost volt you can minus that from the voltage of the battery and work out the real value of V. Most questions don't include thw lost volt because it is quite small and considered negible. I think they are...

hi thanks that kinda makes sense, I am just having trouble with the amplitude...x0...how do i work this out and fit it in?

Hi, does anyone know how to calculate the amplitude of a wave knowing the frequency and wavelength

i got 0.2m for the wavelength but am not sure how to use this in the equation would it be -0.2cos5t ?

Hi guys, Having trouble with a question I need to know the displacement of a point on a spring at certain times. At t=0 point p is at its maximum displacement at 2cm point A is further down the spring at p-A = 0.4m A transverse wave of frequency 5Hz is moving along the spring at...

i thought i was just to put the factor into the equation. Not sure what other way to do. Is the second part correct?

simultaneous polynominals! stuck on this coursework question The cubic polynominal f(x)= 4x^3+ax^2+bx+6 has a factor (x-2) when it is divided by (x+1) it has a remainder 0f -15 find the values of a and b I did as follows factor (x-2) f(-2) 4(-2)^3+a(-2)^2+b(-2)+6=0 equals 4a-2b=26...

I have been asked to draw the graph of the function f(x)= (x+3)/(x-2) I have found where it cuts the y-axis by putting x=0 but am unsure of how to find the x value. I found the inverse of f(x)= (x+3)/(x-2) which gave me x= (y+3)/(y-2) then set y=0 which again gave me x=-3 I have checked...

ahhh yer that makes sense :) thanks

is it because g is a gunction of x, not x itself!? am i doing it correctly then? :)