In this system we have the conservation of angular momentum: L₁ = L₂
We can write L = m·r²·ω
Therefore, we will have:
m₁ · r₁² · ω₁ = m₂ · r₂² · ω₂
The mass stays constant, therefore it cancels out, and we can solve for ω<span>₂:
</span>ω₂ = (r₁/ r₂)² · ω<span>₁
Since we know that r</span>₁ = 4r<span>₂, we get:
</span>ω₂ = (4)² · ω<span>₁
= 16 </span>· ω<span>₁
Hence, the protostar will be rotating 16 </span><span>times faster.</span>
True! In order for work to be done, a force must cause movement.
To determine the acceleration of the car, we use equation of motion
Here, v is final velocity of the car, u is the initial velocity of the car, a is the acceleration of the car in time t.
Given,
, u=0 because car accelerate from 0 and t = 3.40 s.
Substituting these values in above equation, we get

In mi/ h.s,
1 m = 0.000621371 mile.
1 s = (1/3600 ) hour = 0.000277778 hour.
Therefore,

The foam decreases the time of impact.
<h3 />
<h3>What is Impulse?</h3>
The Impulse applied to an object causes a change in the momentum of the object. Impulse is the product of force and time of impact.
J = Ft
where;
- J is the impulse
- F is the applied force
- t is the time of impact
The increase in the time of impact increases the impulse experienced by the object, and a decrease in the time of impact causes a decrease in the impulse experienced by the object.
Thus, we can conclude that the foam decreases the time of impact because it cushions the effect of impact.
Learn more about impulse here: brainly.com/question/25700778
<h3>
Answer:</h3>

<h3>
General Formulas and Concepts:</h3>
<u>Math</u>
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
<u>Physics</u>
<u>Forces</u>
SI Unit: Newtons N
Free Body Diagrams
Gravitational Force: 
- m is mass (in kg)
- g is Earth's gravity (<em>9.8 m/s²</em>)
Normal Force: 
Newton's Law of Motions
- Newton's 1st Law of Motion: An object at rest remains at rest and an object in motion stays in motion
- Newton's 2nd Law of Motion: F = ma (Force is equal to [constant] mass times acceleration)
- Newton's 3rd Law of Motion: For every action, there is an equal and opposite reaction
<h3>
Explanation:</h3>
<u>Step 1: Define</u>
1 kg book at <em>rest</em>
<u>Step 2: FBD</u>
<em>See Attachment</em>
<em>Draw a free body diagram to label the forces acting upon the book. We see that we would have gravitational force from Earth pointing downwards and normal force from the surface of the desk pointing upwards.</em>
<em>Since the book is not moving, we know that ∑F = 0 (sum of forces equal to 0).</em>
<u>Step 4: Find Normal Force</u>
- Define Forces [Newton's Law of Motions]:

- [Newton's Law of Motions] Substitute in forces:

- [Newton's Law of Motions] [Addition Property of Equality] Isolate
: 
- [Newton's Law of Motions] Substitute in
: 
- [Newton's Law of Motions] Rewrite:

- [Newton's Law of Motions] Substitute in variables:

- [Newton's Law of Motions] Multiply:
