Answer:
Explanation:
Acceleration is defined as the change in velocity divided by the time it took to produce such change. The formula then reads:
Where Vf is the final velocity of the object, (in our case 80 m/s)
Vi is the initial velocity of the object (in our case 0 m/s because the object was at rest)
and t is the time it took to change from the Vi to the Vf (in our case 0.05 seconds.
Therefore we have:
Notice that the units of acceleration in the SI system are 
(meters divided square seconds)
1 mA = 0.001 A
Therefore, 5 mA = 0.001 * 5
=0.005 A
Resistance = voltage / current
= 100 / 0.005
= 20000 ohms
Current = voltage / resistance
= 25 / 20000
= 0.00125 A (or) 1.25 mA
B. Metals are usually defined to be from group 1 to group 13 in the periodic table which has 1-3 electrons in the outermost shell. They easily give them up which explains their conductivity.
The strength of a field force changes with distance from the sourceof the field-stronger closer to the source, weaker farther away from the source. The source can be either a mass, a charged particle, or a magnetic pole.
