For this problem, we would be using the formula: Vf^2 = Vi^2 + 2ad
where:
Vf = 400m/s
Vi = 300m/s
a = ?
d = 4.0km
= 4000m
400^2 = 300^2 + 2a4000
a = [ 160000 - 90000 ] / 8000
a = 8.75m/s^2
rounding it off to 2 significant figures, will give us 8.8 m/s^2.
Answer:

Explanation:
By energy conservation we know that spring energy is converted into kinetic energy of the block
so we will have

so we will have

now we will have same thing for another mass 4m which moves out with speed 5v
so we have

now from above two equations we have

so we have

Answer:
All you gotta do is search it up. ask the same question you asked on here, type it into google, it'll teach you a lot more than your actual teachers.
Explanation:
Answer:
These molecules push the layer of molecules down / near, so they also start to vibrate. In this way, the oscillation is followed by one molecule next to it.
Answer:
The weight of the body, W = 793.8 m/s²
Explanation:
Given,
The volume of the body, v = 45,000 cm³
The density of the body, ρ = 1.8 g/cm³
The mass of the body is given by the formula,
m = ρ x v
= 1.8 g/cm³ x 45,000 cm³
= 81,000 g
Hence, the mass of the body is m = 81 kg
The weight of the body,
W = m x g
= 81 kg x 9.8 m/s²
= 793.8 m/s²
Hence, the weight of the body, W = 793.8 m/s²