Question

A dog accelerates at 1.50 m/s^2 to reach a velocity of 13.5 m/s while covering a distance of 49.3 m. What was his initial velocity?

A) 34.4 m/s
B) 5.86 m/s
C) 18.2 m/s
D) 330. m/s

Answer 1

Step-by-step explanation:

The equation you need for this is a one-dimensional:

`v_f^2=v_0^2 +2a`Δx (sorry that looks weird. It is all one equation, even though it's "crooked"!)

We have final velocity, acceleration, and the displacement, and we are looking for initial velocity. I see after working this out that you don't use the die-hard rules for significant digits, so I adapted to get an answer that matches exactly what one of your choices is. Filling in:

`(13.5)^2=v_0^2+2(.50)(49.3)` and

`(13.5)^2-2(1.50)(49.3)=v_0^2` and

`√((13.5)^2-2(1.50)(49.3))=v_0` so

v₀ = 5.86 m/s