Answer:’B’
Explanation:Since, the nucleus is in the middle and it carries protons which carry positive charge and neutrons which carry no charge.
Answer:
where is the picture of star
Answer:
Frequency=10 Hz
Period=0.1 s
Explanation:
Frequency of a wave is the number of complete cycles per unit time. Usually, frequency is cycles per second, with unit as Heartz
Given cycles of the wave as 200 and time as 20 seconds
Frequency=200÷20=10 cycles per second
Therefore, frequency is 10 Hz
Period is usually the reviprocal of frequency hence reciprocal of 10 Hz will be 1/10=0.1 s
