F = m*a
30 N = (ma + mb) * a
30 = 5*a
a = 6 m/s ^2
F de B em A
30 - F de B,A = ma * a
30 - F de B em A = 3 * 6
30 - 18 = F de B em A
12 = F de B em A
Resposta: 6 m/s^2 e 12N
Bate com o gabarito, man? Ou eu tô viajando aqui?
Abç!
A. because as the merry-go-round spins the child accelerates towards the center of the merry-go-round at a uniform rate.
Answer:
The law of reflection (in physics) states that when a light ray is incident on a plane surface, the incident ray, the reflected ray and the “normal” to the surface of the mirror all lie in the same plane. It also states that the angle the incident ray makes with the normal is equal to the angle that the reflected ray makes with the normal.
The answer is both.
For kinetic energy:
KE = 1/2*m*v^2 = 0.5*20,000 grams*5 = 50,000 J
For gravitational potential energy:
Pe = mgh = 20,000 grams*9.81 m/s^2*2 m = 392.2 J