a. 7.0 m/s
First of all, we need to convert the angular speed (1200 rpm) from rpm to rad/s:

Now we know that the row is located 5.6 cm from the centre of the disc:
r = 5.6 cm = 0.056 m
So we can find the tangential speed of the row as the product between the angular speed and the distance of the row from the centre of the circle:

b. 
The acceleration of the row of data (centripetal acceleration) is given by

where we have
v = 7.0 m/s is the tangential speed
r = 0.056 m is the distance of the row from the centre of the trajectory
Substituting numbers into the formula, we find

Answer:
C.
Explanation:
If there are the same number of protons (+) as electrons (-) they will cancel out and make the atom neutral.
Answer:
The magnitude of the net force is √2F.
Explanation:
Since the two particles have the same charge Q, they exert the same force on the test charge; both attractive or repulsive. So, the angle between the two forces is 90° in any case. Now, as we know the magnitude of these forces and that they form a 90° angle, we can use the Pythagorean Theorem to calculate the magnitude of the resultant net force:

Then, it means that the net force acting on the test charge has a magnitude of √2F.
The current in the 50 Ω resistor is A) 1.2 A
The diagram represents a chain reaction that is caused by nuclear fission.
<h3>What is a nuclear fission reaction?</h3>
A nuclear fission reaction is a reaction in which the nucleus of a larger atom is split into two or more smaller nucleus of atoms.
Nuclear fission can proceed in the form of a chain reaction in which the products of the first fission reaction are used to initiate further fission reactions.
Therefore, the diagram represents a chain reaction that is caused by nuclear fission.
Learn more about nuclear fission at: brainly.com/question/22155336
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