B. Because chemical changes (for example, burning turning something into ashes) can change it's appearance while physical changes (for example, crumpling a piece of paper) can aswell.
Answer:
C:
Explanation:
either C or A but A seems unlikely after multiple attempts. Although the question doesn't make it clear whether the balance is electric either way it could be wrong in someway and seems to be the most likely.
When an object is falling and reaches a constant velocity, the net force on the object is <em>zero</em> (it's not accelerating), and the weight of the object is equal to <em>the force of air resistance against the object</em>. (choice-D)
The initial voltage at the primary= 750 V
Explanation:
for a transformer
Es/ Ep= Ns/ Np
Es= secondary voltage= 240 V
Ep= primary voltage
Ns= number of turns in the secondary=8
Np= Number of turns in the primary=25
so 240/Ep=8/25
Ep=750 V
Answer:
Explanation:
Recall that the formula for an inductance (L) for coil on N turns, are A and current I is given by:
Then, for the first coil we have;
and for coil 2 we have:
then, the quotient L1/L2 can be written as:
