@Rathin

Hi, i'm glad that you got the answer that I got but the answer in my book states 3.02 * 10^8 m

Unless we both made the same mistake, I got that answer too so it may be a book error

How do you do quesiton 9, graph relates to question

http://imgur.com/6lYLwa2

Hi, I'm a bit rusty on this, so someone correct me if I'm wrong.

I'm assuming at the start of the question it means 6000km, not 600km as that's what's shown on the graph.

J = Nm

Change in the energy is the change in kinetic energy, final kinetic energy is zero, so the initial kinetic energy is the change in kinetic energy.

Change in kinetic energy is the area under the graph, so just the number of squares * value of squares (in this case 2*(1/2)*10^6 = 10^6)

16 squares * 10^6

1.6*10^7 Joules

Or you could multiply each of the values and calculate the difference aka change in energy

Initial energy = 11*6.0*10^6 = 6.6*10^7

Final energy = 6.3*8.0*10^6 = 5.0*10^7

Difference = 1.6*10^7 Joules

Hope this helps