The word to fill in the blank is "equal". Because the time taken to rotate (spin on its axis) is equal to the time of revolution (going around the earth), this means that both have the same rate of angular rotation. So for every bit that the moon goes around its orbit around earth, the moon itself rotates accordingly to present the exact same side to earth.
Coulomb's law:
Force = (<span>8.99×10⁹ N m² / C²<span>) · (charge₁) · (charge₂) / distance²
= (</span></span><span>8.99×10⁹ N m² / C²<span>) (1 x 10⁻⁶ C) (1 x 10⁻⁶ C) / (1.0 m)²
= (8.99×10⁹ x 1×10⁻¹² / 1.0) N
= 8.99×10⁻³ N
= 0.00899 N repelling.
Notice that there's a lot of information in the question that you don't need.
It's only there to distract you, confuse you, and see whether you know
what to ignore.
-- '4.0 kg masses'; don't need it.
Mass has no effect on the electric force between them.
-- 'frictionless table'; don't need it.
Friction has no effect on the force between them,
only on how they move in response to the force.
</span></span>
Explanation:
It is given that,
Mass of the woman, m₁ = 52 kg
Angular velocity, 
Mass of disk, m₂ = 118 kg
Radius of the disk, r = 3.9 m
The moment of inertia of woman which is standing at the rim of a large disk is :


I₁ = 790.92 kg-m²
The moment of inertia of of the disk about an axis through its center is given by :


I₂ =897.39 kg-m²
Total moment of inertia of the system is given by :


I = 1688.31 kg-m²
The angular momentum of the system is :



So, the total angular momentum of the system is 4980.5 kg-m²/s. Hence, this is the required solution.
Answer:
150J
Explanation:
Formula : <u>Work</u><u> </u><u>done</u>
Force x distance
work done = force x distance
Distance should be measured in meters
300÷100=3m
work done = 450 x 3
=150J