Question

A body travels in a semicircular path of radius 10 m starting its motion from point Ato point B .calculate the distance and displacement

Answer 1

Topic :- Motion in straight line

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$\maltese\:\underline{\textsf{\textbf{AnsWer :}}}\:\maltese$

We're given , Radius (r) = 10 m

As per the question, the shortest distance between the final position B and initial position A is AB = 2 × Radius = 2r

Hence, the displacement of the person is :

$\longrightarrow\:\:\sf Displacement = 2 \times Radius$

$\longrightarrow\:\:\sf Displacement = 2 \times 10$

$\longrightarrow\:\: \underline{ \underline{\sf Displacement = 20 \: m}}$

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Now we know that, distance travelled by the body from A to B is equal to the circumference of the semicircle :

$\longrightarrow\:\:\sf Distance = 2\pi D$

$\longrightarrow\:\:\sf Distance = 2\pi \dfrac{r}{2}$

$\longrightarrow\:\:\sf Distance =\pi r$

$\longrightarrow\:\:\sf Distance = 3.14 \times 10$

$\longrightarrow\:\: \underline{ \underline{\sf Distance = 31.4\: m}}$

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Answer 2

$\large\bold{\underline{\underline{Given:-}}}$

• Radius of semicircular path = 10 m

$\large\bold{\underline{\underline{To \: find:-}}}$

• Distance and Displacement

$\large\bold{\underline{\underline{Formulas \: used:-}}}$

• Circumference of semicircle = πr

$\underline{\mathfrak{understanding \: the \: question...}}$

The given question is requiring the distance and Displacement. For in order to calculate them let's take a semicircle with sides B and C and taking the midpoint as x. Thus taking length between B and x would be 1r and length between x and C be 1r. So length between B and C would be 2r. At last we came to knew about the displacement caused.

$\large\bold{\underline{\underline{Step\: by\: step\: explaination:-}}}$

☯ First calculating the distance that is by using the given formula of circumference of semicircle = πr

where,

• π = 22/7

• r = 10 m

Solving...

→ 22/7 × 10

→ 31.4 m

☯ Now calculating the displacement caused that is by using the given formula and the result we got in understanding the question.

→ 2r

Evaluating values...

→ 2×10

→ 20m