Question

The Graph given shows the positions of a body art different times.
Calculate the Speed of the body as it moves from:

(i) A to B
(ii) B to C, and
(iii) C to D​

Answer 1

$\Large{\bf{\green{\mathfrak{\dag{\underline{\underline{Given:-}}}}}}}$

• Graph shows the positions of a body at different times.

$\Large{\bf{\orange{\mathfrak{\dag{\underline{\underline{To \: Find:-}}}}}}}$

• Speed of the body,

• (i) A to B

• (ii) B to C

• (iii) C to D

$\Large{\bf{\red{\mathfrak{\dag{\underline{\underline{Solution:-}}}}}}}$

We know that,

$\boxed{\pink{\sf Speed \: = \: \dfrac{Distance}{Time}}}$

First let's take,

• A to B

• Distance covered from A to B =

• Final distance covered - intial start =

• 3 - 0 = 3cm

• Time taken =

• Final time taken taken - starting time =

• 5 - 0 = 5s

• Speed =

• $\sf Speed \: = \: \dfrac{3}{5}$

Therefore,

• $\boxed{\purple{\textsf{Speed from A to B = 0.6 cm/s.}}}$

Second let's take,

• B to C

• Distance covered from B to C =

• Final distance covered - initial start =

• 3 - 3 = 0cm

This implies that,

• Body is at rest.

• Time taken =

• Final time taken - starting time =

• 7 - 5 = 2s

• Speed =

• Since, distance i.e numerator is 0.

Therefore,

• $\boxed{\purple{\textsf{Speed from B to C = 0 m/s i.e at rest.}}}$

Third let's take,

• C to D

• Distance covered from A to B =
• Final distance covered - intial start =

• 7 - 3 = 4cm

• Time taken =

• Final time taken taken - starting time =

• 9 - 7 = 2s

• Speed =

• $\sf Speed \: = \: \dfrac{4}{2}$

Therefore,

• $\boxed{\purple{\textsf{Speed from C to D = 2 cm/s.}}}$

Finally,

• Speed from A to B = 0.6 cm/s.

• Speed from B to C = 0 cm/s.

• Speed from C to D = 2 cm/s.

Answer 2

Formula to be used,

$\longrightarrow \underline{ \boxed{ \green{ \sf \: Speed = \dfrac{Distance }{Time} }}}$

Solution : (i)

$\sf \: Here \: distance \: \: covered \: by \: A \: to \: B = [3 - 0] = 3 cm.$

$\sf \: Time \: taken \: to \: cover \: that \: distance = [5 - 2] = 3 \: s.$

$\longrightarrow \sf \: Speed = \dfrac{Distance }{Time}$

$\longrightarrow \sf \: Speed = \dfrac{ 3 \: cm}{3 \: sec}$

$\red {\longrightarrow \sf \: Speed = 1 \: cm / sec}$

$\bf \underline{ = = = = = = = = = = = = = = = = = = = = = = = = = = }$

Solution : (ii)

$\rm \: The \: speed \: of \: the \: body \: as \: it \: moves \: from \: B \: to \: C \: is \: zero.$

$\bf \underline{ = = = = = = = = = = = = = = = = = = = = = = = = = = }$

Solution : (iii)

$\sf \: Here \: distance \: covered \: from \: C \: to \: D = [7 - 3] = 4 \: cm.$

$\sf \: Time \: taken \: to \: cover \: that \: distance = [9 - 7] = 2 \: s.$

$\longrightarrow \sf \: Speed = \dfrac{Distance }{Time}$

$\longrightarrow \sf \: Speed = \dfrac{ 4 \: cm}{2\: sec}$

$\red {\longrightarrow \sf \: Speed = 2 \: cm / sec}$

$\bf \underline{ = = = = = = = = = = = = = = = = = = = = = = = = = = }$