3 years ago

How much physical activity do children and trens need?

Physics

1 answer:

saveliy_v [14]3 years ago

8 0

Answer:

it should be 60 min at least 3 days a week

You might be interested in

1. What is the gravitational force between two 4 kilogram masses separated by a distance of 5

Anon25 [30]

Yo, I assumed that this situation occurs on Earth otherwise the answer would be different.

7 0

3 years ago

Lester plays middle linebacker for dices football team. During one play, he made the following movements. First, he back-pedaled

NikAS [45]

Answer:

Explanation:

missing info .....

4 0

2 years ago

Suppose a vacuum cleaner uses 120 J of electrical energy is 45 J are used to pull air into the vacuum cleaner how efficient is t

Airida [17]

Very efficient because it uses less then half to do the action then the vacuum actually stores.

3 0

4 years ago

How would a person who believes in the geocentric solar

Gemiola [76]

Id say A because the geocentric model is where the earth is at the center of the universe and all other planets, suns, stars, and moons are revolving around it

4 0

3 years ago

An electric current of 200 A is passed through a stainless steel wire having a radius R of 0.001268 m. The wire is L = 0.91 m lo

denis23 [38]

Answer:

The value is $T_m = 435.2 \ K$

Explanation:

From the question we are told that

The current is $I = 200 \ A$

The radius is $R = 0.001268 \ m$

The length of the wire is $L = 0.91 \ m$ \

The resistance is $R = 0.126 \ \Omega$

The outer surface temperature is $T _o = 422.1 \ K$

The average thermal conductivity is $\sigma = 22.5 W/mK$

Generally the heat generated in the stainless steel wire is mathematically represented as

$Q = \frac{Power}{ \pi r^2L}$

$Q = \frac{I^2 R}{ \pi r^2L}$

=> $Q = \frac{200^2 * 0.126}{3.142 * (0.001268)^2 * 0.91}$

=> $Q = 1.096*10^{9}\ W/m^3$

Generally the middle temperature is mathematically represented as

$T_m = T_o + \frac{Q * r^2 }{ 6 * \sigma }$

$T_m = 422.1 + \frac{1.096*10^{-9} * 0.001268^2}{6 * 22.5}$

$T_m = 435.2 \ K$

4 0

3 years ago