What is the law of conservation of energy?

Una tractomula se desplaza con rapidez de 69 km/h. Cuando el conductor ve una vaca atravesada enmedio de la carretera, acciona l

Anestetic [448]

Answer:

Los datos que tenemos:

Rapidez: 69km/h

Tiempo que tarda en frenar = 4s.

Distancia inicial entre la tracto-mula y la vaca = 25m

Ok, la ecuación de desaceleración es:

D = (sf - si)/t

sf = velocidad final = 0m/s

si = velocidad inicial = 69km/h

t = tiempo = 4s

D = -69km/h/4s

ok, 1h = 3600s

D = (-69km/s)*1/(4*3600s) = -0.0048 km/s^2

Entonces la ecuación de aceleración es:

a(t) = -0.0048 km/s^2

Para la velocidad, integramos sobre el tiempo

v(t) = (-0.0048 km/s^2)*t + v0

donde v0 es la velocidad inicial, en este caso v0 = 69km/3600s = 0.0191km/s

v(t) = (-0.0048 km/s^2)*t + 0.0191km/s

Para la posición volvemos a integrar sobre el tiempo, esta vez suponemos la posición inicial igual a cero.

p(t) = (1/2)*(-0.0048 km/s^2)*t^2 + 0.0191m/s*t

Ahora, si p(t=4s) < 25m, esto implica que la tracto-mula no impacto con la vaca.

p(4s) = (1/2)*(-0.0048 km/s^2)*(4s)^2 + 0.0191km/s*4s = 0.038km

y 1km = 1000m

0.038km = 0.038*1000m = 38m

Entonces si, atropello a la vaca.

4 0

4 years ago

Anthony is standing on the top of a building 10 m high holding a 7 kg bowling ball. Mildred dug a 2-m-deep hole next to the base

Leokris [45]

Answer:

B

Explanation:

8 0

3 years ago

Hello <br>Can anyone help me.

labwork [276]

(G)-->Iron and steel industry is called a heavy industry because all the raw material as well as finished goods are heavy and bulky entailing heavy transportation costs. Iron ore, coking coal and limestone are required in the ratio of 4:2:1 approximately. Some quantity of manganese is also required to harden the steel.

(H)-->Sodium is very reactive in nature. When exposed in air, it automatically forms Na2O. When it is put in water it reacts vigorously and starts burning on water. Due to the above reasons Sodium is called an active metal.

(I)-->Down the group, the effective nuclear charge experienced by valence electrons is decreasing because the outermost electrons are far away from the nucleus. Thus, these electrons can be lost easily by the element to form positive ions. Hence, the chemical reactivity of metals increases on going down a group.

(J)-->While moving from top to bottom in a group of the periodic table, the reactivity of non- metals decreases. While moving from top to bottom in a group of non- metals, the atomic size increases with the additional number of shells and the force of attraction between the nucleus and valence shell decreases.