Question

A body moves in a circular track of radius 14 metre find its distance and displacement in

a) 2 rounds , b) 1.5 rounds

please help !!​

Answer 1

Answer:

2 rounds) distance = 175.84 metres, displacement = 0 metres

1.5 rounds) distance = 131.88 metres, displacement = 28 metres

Explanation:

Given:

• Radius of the circular track (r) = 14 metres

To find:

Distance and displacement in:

• a) 2 rounds
• b) 1.5 rounds

Distance:

Circumference of the circular track = 2πr

Circumference of the circular track = 2×3.14×14

Circumference of the circular track = 6.28×14

Circumference of the circular track = 87.92 metres

Distance in 2 rounds = 2×87.92 = 175.84 metres

Distance in 1.5 rounds = 1.5×87.92 = 131.88 metres

Displacement:

At the end of 2 rounds, the body would come back to the initial position and hence the displacement will be equal to 0 metres

At the end of 1.5 rounds the displacement would be equal to diamter, which is equal to 28 metres

Answer 2

Given :-

Radius of circular track = 14 m

To find :-

The distance and displacement of body

1) 2 rounds

2) 1.5 rounds

Now it's a circular track so it's distance is equal to the circumference of circle

$\boxed{\sf \ Circumference \ of \ circle = 2 \pi r}$

Now solve ,1 ) 2 rounds

Distance for 2 rounds = 2× Circumference of circle

$\implies\sf Distance = 2\times 2 \pi r\\ \\ \implies\sf Distance = 4\times \dfrac{22}{\cancel7}\times \cancel{14}\\ \\ \implies\sf Distance = 4\times 22\times 2\\ \\ \implies\sf Distance = 176m$

Now the displacement for 2 rounds will be 0 , ( he came back to initial point v=u=0 )

Now 2) , 1.5 rounds

Distance = 1.5 × circumference of circle (2πr)

$\implies\sf Distance = 1.5\times 2\times \dfrac{22}{\cancel7}\times \cancel{14}\\ \\ \implies\sf Distance = 66\times 2\\ \\ \implies\sf Distance = 132 m$

Displacement for 1.5 rounds

Displacement for 1 rounds = 0

0.5 rounds = 2r = 2×14 = 28cm

Displacement for 1.5 rounds = 0+28= 28m