Answer:
r = 0.22m
Explanation:
To find the radius of the circular trajectory, you first take into account that the centripetal force of the charged particle, is equal to the electric force between the particle that is moving and the particle at the center of the orbit.
Then, you have:
(1)
m: mass of the particle = 20g = 20*10-3 kg
ac: centripetal acceleration = ?
q: charge of the particle = 5*10^-6C
Fe: electric force between the charges
The electric force is given by:
(2)
r: radius of the orbit
q': charge of the particle at the center of the orbit = -5*10^-6C
Furthermore, the centripetal acceleration is:
(3)
v: speed of the particle = 7m/s
You replace the expressions (2) and (3) in the equation (1) and solve for r:

Finally, you replace the values of all parameters in the previous expression:

The radius of the circular trajectory is 0.22m
Newton's second law of motion<span> can be formally stated as follows: The acceleration of an object as produced by a net </span>force<span> is directly proportional to the magnitude of the net </span>force, in the same direction as the netforce<span>, and inversely proportional to the mass of the object</span>
"Average velocity" is the vector among the choices given in the question that describes <span>how fast an object moves over a long time interval. The correct option among all the options that are given in the question is the last option or the fourth option. I hope the answer has helped you.</span>
(I'm lucky to have a computer ... It was only through the miracle of
modern digital technology that I was able to flip your photo right-
side-up to where I could read it.)
Here's how to figure out things like this:
The circle on the left side labeled ' <em>G</em> ' is the <em><u>G</u></em>enerator or battery
that powers this whole circuit and all the devices in it. In order for
any device to work, you need to be able to set your pencil down at
the top of the Generator, and find a path through the circuit and
through that device, where current can flow all the way around to
the bottom of the Generator. If you ever come to an open switch,
then current stops there, and you have to find another way through.
If the path you found takes you back to the bottom of the generator but
it doesn't go through one of the devices, then that device doesn't work.
Look at the picture. If you open switch S-4, then Device-4 can't work,
because current can't go through it from one end of the Generator to
the other end. But all of the other devices still work.
I can see 2 ways to turn off Device-3 with a single switch ... either
open switch S-5, or else open switch S-1. Unfortunately, I think
either way will shut off all 5 devices.