Answer:
(a) The ratio of turns in the primary and secondary coils of her transformer is 1.833
(b) The ratio of input to output current is 0.55
(c) To increase the output voltage, you can either increase the number of turns in the secondary coil (step-up) or increase the input current. Therefore, the Chinese person has to increase the input current of the transformer to achieve an increased output voltage that can power her 220 V appliances.
Explanation:
Given;
input voltage,
= 220 V
output voltage,
= 120 V
General transformer equation is given as;

where;
Np is number of turns in the primary coil
Ns is number of turns in the secondary coil
Is - is the secondary current or output current
Ip - is the primary current or input current
(a) The ratio of turns in the primary and secondary coils of her transformer;

(b) The ratio of input to output current;

(c) To increase the output voltage, you can either increase the number of turns in the secondary coil (step-up) or increase the input current. Therefore, the Chinese person has to increase the input current of the transformer to achieve an increased output voltage that can power her 220 V appliances.
Answer:
what are they ill have a look
Explanation:
Answer:
It can be seen from the operation of pin-hole camera, formation of shadows and eclipse.
Explanation:
The phenomenon of light traveling in a straight line is known as rectilinear propagation of light.
One this evidence can be seen from the operation of pin-hole camera, which depends on rectilinear propagation of light
Also two natural effects that result from the rectilinear propagation of light are the formation of Shadows and Eclipse.
The velocity of the object is zero (the object is at rest)
Explanation:
A position vs time graph represents the motion of an object; in particular:
- The position of the object x(t) is represented on the y-axis
- The time t is represented on the x-axis
For a position-time graph, the slope of the graph is given by

where
is the change in position
is the change in time
However, we see that this is equivalent to the definition of velocity:

Therefore, the slope of a position-time graph is equivalent to the velocity of the object.
And so, a horizontal segment on a position vs time graph means that the object has zero velocity (because the slope is zero).
Learn more about velocity:
brainly.com/question/5248528
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