Answer:
First, let us make some simplifications in notation. Taking the initial time to be zero, as if time is measured with a stopwatch, is a great simplification. Since elapsed time is
Δ
t
=
t
f
−
t
0
, taking
t
0
=
0
means that
Δ
t
=
t
f
, the final time on the stopwatch. When initial time is taken to be zero, we use the subscript 0 to denote initial values of position and velocity. That is,
x
0
is the initial position and
v
0
is the initial velocity. We put no subscripts on the final values. That is,
t
is the final time,
x
is the final position, and
v
is the final velocity. This gives a simpler expression for elapsed time—now,
Δ
t
=
t
. It also simplifies the expression for displacement, which is now
Δ
x
=
x
−
x
0
. Also, it simplifies the expression for change in velocity, which is now
Δ
v
=
v
−
v
0
. To summarize, using the simplified notation, with the initial time taken to be zero,
Δ
t
=
t
Δ
x
=
x
−
x
0
Δ
v
=
v
−
v
0
}
Explanation: