Physics, 27.12.2020 18:10 shoafmckenzie1962

Dos automóviles que marchan en el mismo sentido, se encuentran a una distancia de 126 Km. Si el más lento va a 42 Km/h, calcular la velocidad del más rápido, sabiendo que le alcanza en seis horas.

Answers: 2

Show answers

Answers

Answer from: ag1606

La velocidad del más rápido deberá ser de 63 Km/h

Explanation:

Movimiento Rectilíneo Uniforme (MRU)

Un cuerpo se dice que tiene MRU cuando recorre iguales distancias en tiempos iguales y en línea recta.

Tenemos dos automóviles viajando en el mismo sentido. Uno, el más lento va por delante del otro que le ancanzará en t=6 horas una vez que supere la ventaja que le lleva el otro.

La velocidad se puede calcular con la fórmula:

$\displaystyle v=\frac{x}{t}$

Donde x es la distancia y t el tiempo que tarda en recorrerla.

El vehículo más rápido alcanzará al otro cuando logre superar los x=126 Km que le lleva. Si esto lo hace en t=6 horas, entonces la velocidad adicional que deberá desarrollar es:

$\displaystyle v=\frac{126}{6}=21\ Km/h$

Esa velocidad se suma a la del primer vehículo y tendremos la velocidad necesaria: 42 Km/h + 21 Km/h = 63 Km/h

La velocidad del más rápido deberá ser de 63 Km/h

Answer from: Quest

Mfjh f fb gcbb etyb yryh htbgh g yrjjj t n j tj

Answer from: Quest

russian is not my first language, so i'm afraid i can't write out an answer in russian, but hopefully you can find a way to do so. here's my best translation of the problem: you're given a plot of a particle's position in one-dimensional space over time, and you're asked to find either the total distance traveled by the particle after 6 seconds had elapsed, or the total displacement of the particle after 6 seconds.

if you want the total distance traveled, you would first need to determine the particle's velocity as a function of time, then integrate that over the 6-second interval. we know the position function is quadratic with roots at 0 and 6, so we have

$x(t)=ax(x-6)$

where $a$ is unknown. because the position is parabolic, there is symmetry about the midpoint at $t=3$ , and we know that

$x(3)=10\implies -9a=10\implies a=-\dfrac{10}9$

so that the position function is

$x(t)=-\dfrac{10}9x(x-6)$

which means the velocity is

$v(t)=\dfrac{\mathrm dx}{\mathrm dt}=-\dfrac{20}9x+\dfrac{60}9$

then the total distance traveled is

$\displaystyle\int_{t=0}^{t=6}|v(t)|\,\mathrm dt=\left\{\int_{t-0}^{t=3}-\int_{t=3}^{t=6}\right\}v(t)\,\mathrm dt=20$

so the total distance traveled is 20 m.

on the other hand, if you want to find displacement: the particle starts at $x=0$ and ends at $x=0$ , so its displacement is 0.

Other questions on the subject: Physics

Physics, 21.06.2019 17:30, corynanderson16

The position of a dragonfly that is flying parallel to the ground is given as a function of time by r⃗ =[2.90m+(0.0900m/s2)t2]i^− (0.0150m/s3)t3j^. a: at what value of t does the velocity vector of the insect make an angle of 34.0 degree clockwise from the x-axis? b: at the time calculated in part (a), what is the magnitude of the acceleration vector of the insect? c : at the time calculated in part (a), what is the direction of the acceleration vector of the insect?

Answers: 1

continue

Physics, 21.06.2019 18:20, gordwindisney3747

What color would an object that reflects green and blue light appear to be in white light? a. blue b. cyan c. magenta d. black

Answers: 1

continue

Physics, 22.06.2019 02:40, jordynsmith02

If the wheels lock when braking suddenly the vehicle: a: loses traction b: lose steering wheel ability c: gain speed slightly d: gain steering ability

Answers: 1

continue

Physics, 22.06.2019 06:00, tylorroundy

Aball is thrown upward. at a height of 10 meters above the ground, the ball has a potential energy of 50 joules (with the potential energy equal to zero at ground level) and is moving upward with a kinetic energy of 50 joules. what is the maximum height h reached by the ball? consider air friction to be negligible. 1. h ≈ 10 m 2. h ≈ 50 m 3. h ≈ 30 m 4. h ≈ 40 m 5. h ≈ 20 m 003 10.0 points which of the two object shown below has the greatest kinetic energy? a m b 1 2 m v 2v 1. kinetic energies are the same. 2. a 3. b 4. unable to determine. 004 10.0 points tim, with mass 74.6 kg, climbs a gymnasium rope a distance of 3.1 m. the acceleration of gravity is 9.8 m/s 2 . how much potential energy does tim gain? answer in units of j. 005 10.0 points a car is moving at 64 miles per hour. the kinetic energy of that car is 5 × 105 j. how much energy does the same car have when it moves at 111 miles per hour? answer in units of j. 006 10.0 points an 102 kg man climbs up a 1 m high flight of stairs. the acceleration of gravity is 9.81 m/s 2 . w

Answers: 3

continue

You know the right answer?

Dos automóviles que marchan en el mismo sentido, se encuentran a una distancia de 126 Km. Si el más...