Physics Unit 2 Question, help needed

Sorry if this is a bit of a 'noob' question, but how will I go about calculating this? I can't find any instructions in my revision guide, which was made by AQA themselves :/

Sorry if this is a bit of a 'noob' question, but how will I go about calculating this? I can't find any instructions in my revision guide, which was made by AQA themselves :/

We did this question in class and it's one of those sneaky questions. 0-6 seconds it's accelerating and 6 seconds onward it's constant speed hence the straight line. Hope that will make it easier to understand the Q and work it out.

Worked it out, thanks!! The only thing is that its hard to see where it becomes a straight line, so there should be a range of answers really. It's these type of questions that are 100x harder in exam conditions when you cant think straight :/

no pun intended lol

I don't think you have to know where does it become straight. You can just choose a random interval where the line is straight and calculate dy/dx

doing that gets me a really close answer, but not close enough according to the mark scheme :/

I think you can get the exact answer, for example you choose the interval of 8 and 10 and you get (170-125)/(10-8)=22.5, which should be the answer. If the mark scheme requires you to choose the interval of 6 and 10, they are too harsh.

Yeah, 8 and 10 works. But I've been doing 7.8 and 10 all along, which should still give me 22.5, but it doesn't (170-120)/(10-7.8) = 22.72727272...

Unless I'm doing something wrong :/