Question

find the acceleration of a car which is moving with a speed of 8m/s after 5 second it change into 23m/s class 9​

Answer 1

Provided that:

• Initial velocity = 8 mps
• Final velocity = 23 mps
• Time = 5 seconds

To calculate:

• Acceleration

Solution:

• Acceleration = 3 mps sq.

Using concept(s):

• To solve this question we can use either first equation of motion or acceleration formula.

Using formula(s):

• Acceleration formula:

• a = (v-u)/t

• First equation of motion:

• v = u + at

Required solution:

By using acceleration formula!

»»» a = (v-u)/t

»»» a = (23-8)/5

»»» a = 15/5

»»» a = 3 mps sq.

»»» Acceleration = 3 mps sq.

By using first equation of motion!

»»» v = u + at

»»» 23 = 8 + a(5)

»»» 23 = 8 + 5a

»»» 23-8 = 5a

»»» 15 = 5a

»»» a = 15/5

»»» a = 3 mps sq.

»»» Acceleration = 3 mps sq.

Explore more:

$\begin{gathered}\boxed{\begin{array}{c}\\ \bf What \: is \: acceleration? \\ \\ \sf The \: rate \: of \: change \: of \: velocity \: of \: an \\ \sf object \: with \: respect \: to \: time \\ \sf is \: known \: as \: acceleration. \\ \\ \sf \star \: Negative \: acceleration \: is \: known \: as \: deceleration. \\ \sf \star \: Deceleration \: is \: known \: as \: retardation. \\ \sf \star \: It's \: SI \: unit \: is \: ms^{-2} \: or \: m/s^2 \\ \sf \star \: It \: may \: be \: \pm ve \: or \: 0 \: too \\ \sf \star \: It \: is \: a \: vector \: quantity \\ \\ \bf Conditions \: of \pm ve \: or \: 0 \: acceleration \\ \\ \sf (1) \: Positive \: acceleration: \: \sf When \: \bf{u} \: \sf is \: lower \: than \: \bf{v} \\ \sf (2) \: Negative \: acceleration: \: \sf When \: \bf{v} \: \sf is \: lower \: than \: \bf{u} \\ \sf (3) \: Zero \: acceleration: \: \sf When \: \bf{v} \: \sf and \: \bf{u} \: \sf are \: equal \end{array}}\end{gathered}$

Answer 2

• initial velocity=u=8m/s
• Final velocity=v=23m/s
• Time=t=5s

We know

$\boxed{\sf Acceleration=\dfrac{v-u}{t}}$

$\\ \sf\longmapsto Acceleration=\dfrac{23-8}{5}$

$\\ \sf\longmapsto Acceleration=\dfrac{15}{5}$

$\\ \sf\longmapsto Acceleration=3m/s^2$