Answer:a) 34.5 N; b) 24.5 N; c) 10 N; d) 1J
Explanation: In order to solve this problem we have to used the second Newton law given by:
∑F= m*a
F-f=m*a where f is the friction force (uk*Normal), from this we have
F= m*a+f=5 Kg*2 m/s^2+0.5*5Kg*9.8 m/s^2= 34.5 N
then f=uk*N=0.5*5Kg*9.8 m/s^2= 24.5N
the net Force = (34.5-24.5)N= 10 N
Finally the work done by the net force is equal to kinetic energy change so
W=∫Force net*dr= 10 N* 0.1 m= 1J
Answer:
The evidence is conclusive; aggression and violence in the media lead to aggression and violence in the general population.
Explanation:
good luck
Answer:
f= 4,186 10² Hz
Explanation:
El sistema descrito es un pendulo de torsión que oscila con con velocidad angular, que esta dada por
w = √ k/I
donde ka es constante de torsion de hilo e I es el momento de inercia del disco
El momento de inercia de indican que giran un eje que pasa por enronqueces
I= ½ M R2
reduzcamos las cantidades al sistema SI
R= 1,4 cm = 0,014 m
M= 430 g = 0,430 kg
substituimos
w= √ (2 k/M R2)
calculemos
w = RA ( 2 370 / (0,430 0,014 2)
w = 2,963 103 rad/s
la velocidad angular esta relacionada con la frecuencia por
w =2pi f
f= w/2π
f= 2,963 10³/ (2π)
f= 4,186 10² Hz
Answer:
80m
Explanation:
u=20,R=?,sin theta=1,g=10
R=u²sin2theta/g
R=20²x2/10
R=400x2=800/10
R=80m
Answer:
v = 2,99913 10⁸ m / s
Explanation:
The velocity of propagation of a wave is
v = λ f
in the case of an electromagnetic wave in a vacuum the speed that speed of light
v = c
When the wave reaches a material medium, it is transmitted through a resonant type process, whereby the molecules of the medium vibrate at the same frequency as the wave, as the speed of the wave decreases the only way that they remain the relationship is that the donut length changes in the material medium
λ = λ₀ / n
where n is the index of refraction of the material medium.
Therefore the expression is
v =
Let's look for the frequency of blue light in a vacuum
f =
f =
f = 6.667 10¹⁴ Hz
the refractive index of air is tabulated
n = 1,00029
let's calculate
v =
450 10-9 / 1,00029 6,667 1014
v = 2,99913 10⁸ m / s
we can see that the decrease in speed is very small