Answer:
Electric field, 
Explanation:
It is given that,
Charge, Q = +6.1 C
Distance, r = 21 cm = 0.21 m
We need to find the electric field. It is given by :
So, the electric field at this distance is 
. Hence, this is the required solution.
Not enough information is given to answer this question.
Explanation:
1 mega Hertz = 1000000 hertz
Option B The thickness of the central portion of a thin conveying lens can be determined very accurately by using a micrometer screw gauge.
<h3>What can be measured using a micrometer screw gauge?</h3>
One micrometer of thickness can be measured with a micron micrometre screw gauge. A Use of Micrometer Screw Gauge as like example Upon turning the screw of the micrometer screw gauge four times, a 2 mm space is covered.
<h3>What purposes does a micrometer serve?</h3>
A tool known as a micrometer is used to measure solid objects’ lengths, thicknesses, and other dimensions precisely and linearly.
<h3>What is the micrometer screw gauge’s SI unit?</h3>
The SI symbol m is also known as a micron, which is an SI-derived unit of length equaling 1106 meters, where 106 is the SI standard prefix for the prefix “micro-.” A micrometer is one-millionth of a meter.
To know more about screw gauges, visit:
brainly.com/question/4704005
#SPJ13
