Answer:
C. A rubber rod and a glass rod charged this way have opposite charges on them.
Explanation:
When a rubber rod is rubbed against cat fur, it acquires a negative charge, it becomes negatively charged.
When you then try to bring two rubber rod's together, they repel because like charges repel.
Meanwhile, when you rub a glass rod against silk, it loses electrons to the silk material and becomes positively charged.
When you bring two positively charged glass rod's together, they repel, because like charges repel.
However, when you bring the rubber rod and a glass rod together, the attract each other because unlike/opposite charges attract.
<h2>Answer: Gravitational attraction
</h2>
Gravity force causes the clouds of dust and gas to form a protostar. As this <u>attraction force</u> is responsible for gathering and compressing the existing elements in the cloud of gas and dust, heating them during this process.
Then, when the amount of material accumulated by gravitational contraction is large enough, and the temperature and pressure reached high enough, the <u>nuclear fusion</u> process will begin.
To understand it better: The hydrogen nuclei will begin to fuse, generating helium nuclei in the process and releasing huge amounts of energy.
It should be noted that the protostars radiate half of the energy contributed by the gravitational collapse and the other half is invested in heating its core.
Answer:
a luminous ball of plasma
Answer:
Angular momentum, 
Explanation:
It is given that,
Radius of the axle, 
Tension acting on the top, T = 3.15 N
Time taken by the string to unwind, t = 0.32 s
We know that the rate of change of angular momentum is equal to the torque acting on the torque. The relation is given by :
Torque acting on the top is given by :
Here, F is the tension acting on it. Torque acting on the top is given by :
So, the angular momentum acquired by the top is 
. Hence, this is the required solution.
An electric engine turning a workshop sanding rotation at 1.00 × 10² rev/min is switched off. Take the wheel includes a regular negative angular acceleration of volume 2.00 rad/s². 5.25 moments long it takes the grinding rotation to control.
<h3>What is negative angular acceleration?</h3>
- A particle that has a negative angular velocity rotates counterclockwise.
- Negative angular acceleration () is a "push" that is hence counterclockwise.
- The body will speed up or slow down depending on whether and have the same sign (and eventually go in reverse).
- For instance, when an object rotating counterclockwise slows down, acceleration would be negative.
- If a rotating body's angular speed is seen to grow in a clockwise direction and decrease in a counterclockwise direction, it is given a negative sign.
- It is known that a change in the linear acceleration correlates to a change in the linear velocity.
Let t be the time taken to stop.
ω = 0 rad/s
Use the first equation of motion for rotational motion
ω = ωo + α t
0 = 10.5 - 2 x t
t = 5.25 second
To learn more about angular acceleration, refer to:
brainly.com/question/21278452
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