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Graph question

Hey could anyone help me with this question?
What help do you need?
Do you want to know which is the correct answer or do you already know and need an explanation?
What are your thoughts and theories on this. You must have some idea.
Think about the units and what the gradient represents in each case

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Original post by Peanut247
Hey could anyone help me with this question?


Let us consider what the graphs would look like from A - E.

A) Since F = ma, we know that a=F/m, and therefore a = F/5 = 0.2F. This is a graph with a y-intercept of 0, and a gradient of 0.2.

Your graph has a gradient of 20/100 = 0.2, and it has a y-intercept of 0, therefore A is feasible.

B) Since V=IR, I = V/R, and therefore I = V/5 = 0.2V. This graph also has the same form as (A), a y-intercept of 0 and a gradient of 0.2 so it is also feasible.

C) KE = 0.5mv^2 and therefore KE = 0.5*0.4*v^2 = 0.2*v^2. If we plotted KE vs v it won't be linear, but the x-axis is the square of velocity, v^2. Thus y = 0.2x, and thus of the same form as (A) and (B), so this too is feasible.

D) velocity = wavelength*frequency, and therefore wavelength = velocity/frequency, or wavelength = 0.2/frequency. This is of the form 1/x and this is not feasible.

E) Work = Force*Displacement = 0.2*Distance. Again this is of the same form as (A), (B) and (C) so it is feasible.

In summary D is the only answer that is not feasible.

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