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a person pushing a stroller starts from rest, uniformly accelerating at a rate of 0.500 m/s2. What is the velocity of the stroller after it has traveled 4.75 m ?

User Mallendeo
by
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1 Answer

4 votes

Answer:

Approximately
2.18 m\cdot s^(-1).

Step-by-step explanation:

Consider one of the equations for constant acceleration ("SUVAT" equations)


v^(2) - u^(2) = 2 \; a \cdot x,

where


  • v is the final velocity of the object,

  • u is the initial velocity of the object,

  • a is the acceleration of the object, and

  • x is the distance that the object had traveled while its velocity changed from
    u to
    v.

Note that unlike other SUVAT equations, this one does not ask for the time required for the speed of the object to change from
u to
v. Since in this problem, time isn't given, this time-less equation would particular useful.

Here


  • v the final velocity needs to be found.

  • u = 0 for the stroller started from rest.

  • a =\rm 0.500 \;m \cdot s^(-2) is the acceleration of the stroller, and

  • x = \rm 4.75\; m is the distance that the stroller traveled while its velocity changed from
    u to
    v.

Rearrange the equation to isolate the unknown,
v:


v^(2) = u^(2) + 2 \; a \cdot x.

Make sure that all units are standard, so that the unit of the output will also be standard. Apply the equation:


v = \sqrt{u^(2) + 2 \; a \cdot x} = √(0^2 + 2 * 0.500 * 4.75 )\approx \rm 2.18\; m\cdot s^(-1).

Hence the final velocity will be approximately
\rm 2.18 m\cdot s^(-1).

User Eymen Elkum
by
8.0k points