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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