Q11 of 89 Page 48

Figure (3-Q1) shows the x coordinate of a particle as a function of time. Find the signs of ux and ax at t = t1, t = t2 and
t = t3.


The given graph is of x-t. The slope of the curve gives the velocity at the time t. Change in slope gives the acceleration at time t.


At time t1,


Slope is positive Velocity is positive


Slope is increasing Acceleration is positive


At time t2,


Slope is constant Velocity is zero and Acceleration is negative


At time t3,


Slope is negative Velocity is negative


Slope is decreasing Acceleration is negative


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