You stopped the blood and made my head soft
My osmosis experiment involving carrots did not work AT ALL. My results show NOTHING. Some of the carrots SHRANK when they weren't meant to. I was taking results during Ms Peach's sex education class, not a pleasant experience. A load of rowdy, hyperactive year 9s were throwing things and shouting over an extremely patronising video. Believe it or not this ruined my whole day today.
Apart from that I'm feeeling relaxed and revived for a change. Little things cheer me up. Went to Ilford Salvation Army charity shop and bought two scarves. Ate Liquorice Allsorts. Listened to Hard-Fi. Fell asleep fully clothed on my bed at five and woke up at nine. Ate Honeydew melon. Worked a little.
Life isn't so bad, really.
It would be even better if I knew how to answer the following question:
A garden roller consists of a solid steel cylinder of mass 40kg and diameter 0.5m. The roller, fitted with a light handle, is pulled to the top of a uniform slope of length 30m. Given the angle of the slope to the horizontal is 10°, calculate:
a) the fall of height and the loss of P.E. when the roller is released at rest and rolls to the lower end of the slope.
b) its speed at the bottom of the slope.
Oh dear. I can see it's a fairly easy question but I can't do it. I need some help. Might have to go and ask Mr Adcock tomorrow, officially the grumpiest, moaniest, whiniest person ever.
x
9 Comments:
It's a long time since I did mechanics, but start by drawing a diagram and working out all the heights and distances you can. Then look at the question again.
Yeh - I would suggest making a triangle, but I have very limited physics knowledge. And when it reaches the bottom it will be stopped, won't it?
How patronising was the video? Do you think any of the year nines had prior knowledge of the events that took place in the informative media? (NOT FOR PERSONAL INTEREST)
Mike xxx
I already drawn a bloody diagram, I didn't just take one look at the question and not bother, so that's not exactly helpful.
If you must know the video featured various 19 year olds reminiscing about when they were 14, immature, naive and sex-obsessed, and how much they regretted losing their virginity. It was a sort of 'don't do it, kids!' video. Ghastly.
Ah well. As long as the 19 year olds didn't come off all silly, like saying they ACTUALLY regretted the sex. Who would do that? Surely it's not that bad for everyone?
Mike xxx
I don't know why you're being so rude. If you drew the triangle you should be able to at least work out the potential energy
Ep = m g h
where m = mass, g = gravitational field strength, h = height
Then isn't the acceleration just going to be gravity? so given that you have v1 = 0 (at top of slope) and acceleration =~ 10 m/s/s you should be able to work out v2 shouldn't you?
Yeah I got that bit. And I figured out the rest. The formula I actually needed was P.E. = 1/2 m V^2 + 1/2 Iw^2. Those 2s are squares, I is moment of inertia and w should be omega (angular velocity).
Oh yes, of course. Duh. You wouldn't think I had a degree in mathsm would you? Newtonian mechanics were actually one of my strong* points...
* less weak
You didn't do badly considering you haven't done Physics in nine years. I couldn't even remember PE = mgh and I do it four times a week.....
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