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2 years ago

You start walking from a point on a circular field of radius 0.5 km and 1 hour later

Physics

2 answers:

Feliz [49]2 years ago

8 0

Answer:

1). average velocity= displacement/time

= here displacement is zero

= 0/1

= 0 m/s

2). average speed= total distance/time

=2πr/1

=(2×22/7×5/10)/1

22/7

3.14 km/h

hope it helps you

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Explanation:

Dmitry_Shevchenko [17]2 years ago

5 0

Answer:

$\sf \fbox{speed = 3.14 kmph}$

Explanation:

Given:

Radius of circular field (r) = 0.5 Km

Time taken to complete one round of field (t)= 1 hour

To find:

Average speed for the whole journey=?

Solution:

To find the average speed we will have to find the actual distance covered in given time, & the actual distance covered would be equal to the

$\sf \: perimeter \: of \: circular \: field = 2 \pi r \\ \sf 2 \pi r = 2 \times 3.14 \times 0.5 = 3.14 \: km$

Distance covered in 1 hour is 3.14 km,

$\small \sf Average \: speed = \frac{Distance}{Time} = \frac{3.14}{1} \\ \small \sf \fbox{speed = 3.14 kmph}$

$\small\sf \: Thanks \: for \: joining \: brainly \: community!$

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3 years ago

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Arada [10]

Answer:

Average speed of the car = 16.53 m.s

Explanation:

For first 5 seconds:

As the car starts from rest, so the initial speed of the car, u=0

Acceleration, a= 4 m/s^2

So, the final speed (speed at time, t=5 second)

v=u+at

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Distance covered,

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As the car maintained the constant speed of 20 m/s for the next 10 seconds.

Distance traveled in 10 seconds, d=20 x 10 =200 m

For the last 4 seconds:

The car slows down at the rate of 2.0 m / s ^ 2 from the speed of 20 m/s.

As the car slows down, so the acceleration will be negative, i.e a=-2 m/s^2

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s=80-16=64 m.

Considering all three cases, the total distance covered=

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iogann1982 [59]

Answer:

Explanation:

Given

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radius $r=20\ m$

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If Normal force is equal to Gravitational force

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Answer:

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