Answer:
displacement (x) = 0.003798 meters
Explanation:
from the fact that the string is hung vertically we can deduce that:
Total force acting on the mass = Fs (by spring) + Fg (by gravity)
<em>where</em>
Fs = k*x , x is the displacement..
Fg = m*g
then:
Ftot = m*a, <em>but a = 0 m/(s^2) because the mass becames stationary.</em>
Ftot = 0
Fs + Fg = 0
<em>by direction, take down as negative.</em>
Fs - Fg = 0
k*x = m*g
x = m*g/k = [(0.400)(9.8)]/(10.32)
= 0.3798 meters
Answer:
0.88 cm
Explanation:
Initial length at 10°c, L = 23 m
Rise of temperature, Δt = 42 - 10 = 32°c
Coefficient of linear expansion of concrete, α = 12 x 10^(-6) per°c
Minimum spacing to be left = α L Δt
= 8.832 x 10^{-1} cm
= 0.88 cm
Note: I have a chosen a general value of 12 x 10^-6 per deg c for coefficient of expansion of concrete. However, please refer to the value given in your text book and substitute it for an accurate answer.
Answer:
Puesto que la energia cinética traslacional es mucho mayor que la capacidad del chaleco antibalas, la bala atravesaría el chaleco antibalas.
Explanation:
Un chaleco antibalas soporta el disparo de una bala disipando la energía de esta última a través de su propio material. Si sabemos que el chaleco antibalas soporta 120 joules de energía, cabe saber si la energía cinética traslacional es igual o inferior a ese límite, significando que la bala no atravesaría el chaleco.
La energía cinética traslacional de la bala (), in joules, queda expresada con la siguiente fórmula:
(1)
Donde:
- Masa de la bala, en kilogramos.
- Rapidez de la bala, en metros por segundo.
Si sabemos que y , entonces la energía cinética traslacional de la bala es:
Puesto que la energia cinética traslacional es mucho mayor que la capacidad del chaleco antibalas, la bala atravesaría el chaleco antibalas.
Period 1 has only two elements (hydrogen and helium), while periods 2 and 3 have 8 elements. Periods 4 and 5 have 18 elements. Periods 6 and 7 have 32 elements because the two bottom rows that are separated from the rest of the table belong to those periods.