The list of choices that you provided suggests profound silence, which is not too popular among scientists.
Answer:
F=-100N; a=1.3m/s^2
Explanation:
Force is being made by student, so wall counteracts that force by not moving so it is equally opposite.
A. One substance must dissolve in another
Answer:
= 10.3 m/s
Explanation:
We can solve this exercise using the conservation of the moment; the system is formed by the knife and the target, with an isolated system the moment is conserved during the collision
Knife mass m = 22.5 g and its velocity v₁₀ = 39 m / s, the mass of white is M = 300 gr and its velocity is v₂₀ = -2.15 m / s
Before the crash
p₀ = m v₁₀ + M v₂₀
After the crash
= m v₁ₐ + 0
p₀ =
m v₁₀ + M v₂₀ = m
= (m v₁₀ + M v₂₀) / m
Let's calculate
= (0.0225 39.0 + 0.300 (-2.15)) / 0.0225
= 10.3 m / s