Answer:
The recoil speed of the man and rifle is
.
Explanation:
The expression for the force in terms of mg is as follows;
F=mg
Here, m is the mass and acceleration due to gravity.
Rearrange the expression for mass.

Calculate the combined mass of the man and rifle.

Put
.


The expression for the conservation of momentum is as follows as;

Here,
is the mass of the man and rifle,
is the mass of the rifle,
are the initial velocities of the man and bullet and
are the final velocities of the man and rifle and rifle.
It is given in the problem that a rifle with a weight of 25 N fires a 4.5-g bullet with a speed of 240 m/s.
Convert mass of rifle from gram to kilogram.


Put
,
,
,
and
.




Therefore, the recoil speed of the man and rifle is
.
Answer:
The angular acceleration of the pencil<em> α = 17 rad·s⁻²</em>
Explanation:
Using Newton's second angular law or torque to find angular acceleration, we get the following expressions:
τ = I α (1)
W r = I α (2)
The weight is that the pencil has is,
sin 10 = r / (L/2)
r = L/2(sin(10))
The shape of the pencil can be approximated to be a cylinder that rotates on one end and therefore its moment of inertia will be:
I = 1/3 M L²
Thus,
mg(L / 2)sin(10) = (1/3 m L²)(α)
α(f) = 3/2(g) / Lsin(10)
α = 3/2(9.8) / 0.150sin(10)
<em> α = 17 rad·s⁻²</em>
Therefore, the angular acceleration of the pencil<em> </em>is<em> 17 rad·s⁻²</em>
The answer is D No, smaller goals would be better
Rust is not because it does not occur through a chemical process
I think the right answer would be objects pull because gravitational pull is when an object with more mass than an other object would pull the small mass object