frogbutt said:
COuld you please tell me what they've said for the answers to ('07)
27. a and b
26. c
and 21. b
?
27a Classical wave theory could not explain the results being collected in black-body radiation studies and, for the higher frequencies, the predictions were very contradictory to the experimental results being collected. Max Planck developed the idea that the energy was being released in 'quantised bundles and was able to satisfactorily explain the observed experimental results by relating the quantum of energy released by a black body to the frequency of the electrmagnetic radiation emitted. Using the eeqution E=hf, Planck showed that the higher frequencies had a greaterenergy in each quantum and provided a workable solution for the observed experimntal results.
b. Hertz first observed the photoelectric effect while conducting his experiment to confirm the existence of electromagnetic radiation. He noticed that whenever he shone a source of high frequency light on the receiver being used in the experiment there was an increase in the intensity of the spark between the receiver electrodes, ie the light was releasing charges to travel inthe spark.
26c P=VI
Now P(in) = 6x10^3x10=6x10^4W and P(out) = 240x230=5.52x10^4W
P(lost) = 0.48x10^4W = 4800W = 4800J/s. Now 8hrs = 8x60x60=28800s
In 8hours, energylost = 4800x28800 = 1.382x10^8J
21b Torque = force x perpendicular distance to the rotation point
t=fd =(0.2x9.8) x 0.1 = 0.196Nm anticlockwise