Question

For this quiz, we shall return to the radio control car track that we visited briefly on the last quiz. The track is 10 meters long and perfectly straight. A series of reference marks are 1.0 meter apart along the track. A judge sets her stopwatch to 0.0 seconds, then she starts her watch at the instant the car passes the 2.0 meter mark. When the car passes the 8.0 meter mark, the judge reads 3.9 seconds on her stopwatch.Using equation x:=:x0:+:vt x = x 0 + v t , calculate v v in meters per second.

Answer 1

Answer:

$v=1.54\,\,metres\,\,per\,\,second$

Explanation:

The given equation is $x=x_0+vt$ where $x_0$ denotes initial time in the stopwatch and $x$ denotes the distance covered by car.

As the judge starts her watch at the instant the car passes the 2.0 meter mark  $(x_0=2)$ and the judge reads 3.9 seconds on her stopwatch when the car passes the 8.0 meter mark.

Put $x_0=2,\,,\,x=8\,,\,t=3.9$ in equation $x=x_0+vt$

$8=2+3.9t\\8-2=3.9t\\6=3.9v\\v=\frac{6}{3.9}\\ v=1.54\,\,metres\,\,per\,\,second$