Recent content by benhorris

Ah got it, Thanks guys. Was a simple error, i converted it to seconds by doing = 2.6 x 365 x 3600. And i forgot about the hours. 3600 x 24 x 365 x 2.6 = no.seconds gave the correct answer. Silly mistake.

Simple question, but i don't know where to start. The half life of one radioactive isotope of sodium is 2.6 years. Show that its decay constant is 8.4 x 10^-9 s^-1. Thanks in advance, Ben.

Yep, got it. I had the wrong calculation to begin with. But now you know what you have to do to beat the red lights. Travel 38 million metres per second, then the red light will magically turn green. Perfect hey?

okok this is what i did. 620nm - 540nm = 80nm (80nm / 640nm) * 3x10^8 = v v = 38.6 million ms-1

hehe, yeah i know all that. I am just not sure what the differnce in wavelength is etc. I actually got 38 million metres / sec. Not 44. Just wondering what you got. 8-)

If you are driving in a car up to a set of trafic lights that are red, how fast would you need to be going to make the lights appear green? (take the velocity of light to be 3x10^8 ms-1 and the wavelength of red light to be 620nm and the wavelength of green light to be 540nm) Ive calculated...

Thanks by the way. I am sure i have tested your intellectual capabilities to the utmost extreme levels. ... ;-) Thanks once again.

Arnt i a numpty... hehe. W=f*D 11000/0.4 =f f =27500N Duh, flippin ek. Always the simple ones that get me..

KE =0.5mv^2 hence 0.5x220x100 = 11000 J ? Now what - stuck on this Q and its very annoying...

Heres a question for you, can't work out what formula to use so i need some help. A mass of 220KG, hits a cylindrical pole into the ground. Just before it hits the velocity of the mass is 10ms-1. The pole is pushed 0.4 m into the ground, when the mass is droped 5m onto the pole. G =...

Can somebody tell me the advantages of using a rheostat and a potentiometer? Thanks,

Ok thanks guys. Great help, :-)

Can somebody give me a short defination of youngs modulus? I think its the way a material acts under pressure, is this correct?

A student decides to use the tank and water to make a side-show game to raise money at a fete. She places a coin on the bottom of the tank and invites people to drop more coins into cover it – apparently easy to do until you try it. The water is 0.5 m deep. When someone looks vertically into...

Please note that the container is made of perspects, filled with water. The orginal ray of light came into the water at 70 degrees and i have worked out that the refraction of the light ray is 26 degrees. Just need to find the other two parts to the question...