It would be A because he wanted to know more about the physical properties of these particles like their mass
Answer:
A reason why voltmeter is always connected in parallel not in series is:
<u>A Voltmeter has very high resistance to ensure that it's connection do not alter flow of current in the circuit. Now if it is connected in series then no current will be there in the circuit due to it's high resistance. Hence it is connected in parallel to the load across which potential difference is to be measured.</u>
1. Mass
2. Speed
3. Kinetic energy