Hi can someone please explain how the answer to question 20 is C and not D. I can't seem to get 25m please help😣😣😣
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Help! Specimen paper question Watch
- Thread Starter
- 05-06-2016 18:04
- 05-06-2016 18:15
The question is asking for the distance travelled in only the third second. Your calculations have worked out the distance travelled in three consecutive seconds, so you need to subtract the distance travelled in two seconds from that to get the distance travelled in just the third second.
45= 0*3 + 0.5*10*3^2
20=0*2 + 0.5*10*2^2
- 05-06-2016 23:04
When faced with a question like this, I find it useful to draw a quick sketch of the velocity-time graph for this situation. This allows for me to easily visualise the nature of the question. Below, I have added an accurate plot (the sketch doesn't need to be this accurate, of course).
Here, I have shaded the area that represents the displacement that the question is asking for. As we know the equation of the line (), we can calculate the value of at and . Once we haves those, we can calculate the displacement by calculating the area of the trapezium.
I hope that this has been helpful.