Distance and Time: Dimensions of a & b

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The discussion focuses on determining the dimensions of constants a and b in the equation d = at + bt^2, where d represents distance. It clarifies that if distance is measured in meters and time in seconds, then a must have dimensions of velocity (m/s) and b must have dimensions of acceleration (m/s²). The importance of maintaining consistent units throughout the equation is emphasized. Understanding the relationship between distance, velocity, and acceleration is crucial for solving the problem. The conversation highlights the need for clarity in dimensional analysis.
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i need some help with this:

the distance d that a certain particle moves may be calculated from the expression d=at+bt^2, where a and b are constants; and T is the elapsed time. complete the following statement: the dimensions of the quantities a and b are..., respectively

help please i don't get it... thanks
 
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If d is in units of distance, e.g. meters, and time is in units of time, e.g. seconds (s), then if one were to equate d = v*t, v would have to be in units of velocity (speed), e.g. m/s,

distance = (distance/time) * time or distance (m) = velocity (m/s) * time (s). Units must be consistent.

Think about the units of acceleration.
 
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