1. Homework Statement
a narrow beam of laser light (i.e coherent monochromatic light) wavelength 630nm is incident on a grating having 300 lines per mm. a piece of paper is curved 180 degrees beyond the grating. calculate how many spots of red light should be seen
2. Homework Equations...
http://physicsnet.co.uk/a-level-physics-as-a2/current-electricity/circuits/ - right at the bottom
basically if you have a 12v supply with 3 components how can the PD across each component be 12 when 3x12 = 36v?
1. Homework Statement
I am currently revising some AS level Circuit modules and i'm having trouble seeing how the P.D across 3 components in a parallel circuit can each have the same value as the P.D of the battery.
I am probably just being dumb but its just not making sense!
such as this...
I cant see the picture as you need a log on but,
acceleration due to gravity is 9.81ms-2
therefore it must be increasing constantly as it falls, when the ball reaches maximum height acceleration is 0 for an instant
1. Homework Statement
a wire carrying a current of 3.2A has a radius of 1.2mm. the material of the wire has 2.5x10^25 free electrons per cubic metre. the elementary charge is 1.6x10^-19
2. Homework Equations
I=Anev
cross section = pi*r^2
3. The Attempt at a Solution...
Thanks a lot for clearing that up.
So as my line of best fit runs through the first and last point i can indeed use the gradient of 2.
meaning that my experiment had a overall error of 0.5%.
Hi Delphi thanks for your reply, they are very close as I used the same length 3 times and got the average, but thank you :)
ok I see that a value of 2 works as it would be ∏^2 which is 8.96
that makes a error of 0.5% which is very nice.
I can see my error before not making my lengths into...
Thanks for the reply Bruce, I hope i have figured it out:
g=4∏^2L / T^2
so g = 4 x 9.86 x 0.48m / 1.76 = 10.75 m/s/s
9.81 - 10.75 / 9.81 = 9.5% error.
Is this correct Bruce?
1. Homework Statement
The aim of the experiment is to find out if the period of oscillation is proportional to the square root of the length of the pendulum.
We used 5 different lengths and got the average time for 1 oscillation for each length
These are the results:
Length=48cm, Time=1.33s...