Answer:
As we are converting 220V AC into a 5V DC, first we need a step-down transformer to reduce such high voltage. Here we have used 9-0-9 1A step-down transformer, which convert 220V AC to 9V AC. In transformer there are primary and secondary coils which step up or step down the voltage according to the no of turn in the coils.
Selection of proper transformer is very important. Current rating depends upon the Current requirement of Load circuit (circuit which will use the generate DC). The voltage rating should be more than the required voltage. Means if we need 5V DC, transformer should at least have a rating of 7V, because voltage regulator IC 7805 at least need 2V more i.e. 7V to provide a 5V voltage.
I believe the answer is potential energy if i remember correctly.

Actually Welcome to the Concept of the Projectile Motion.
Since, here given that, vertical velocity= 50m/s
we know that u*sin(theta) = vertical velocity
so the time taken to reach the maximum height or the time of Ascent is equal to
T = Usin(theta) ÷ g, here g = 9.8 m/s^2
so we get as,
T = 50/9.8
T = 5.10 seconds
thus the time taken to reach max height is 5.10 seconds.
Answer:
160 W
Explanation:
Power is the ratio of work to time:
(1600 J)/(10 s) = 160 J/s = 160 W
Answer:
the work converted to thermal energy is 40 J.
Explanation:
Given;
work done by the physicist,w = 100 J
height through which the book is raised, h = 0.2 m
efficiency of machine = 60% = 0.6
The useful work done by the machine is calculated as;
useful work = 0.6 x 100 = 60 J
The wasted energy = 100 J - 60 J
The wasted energy = 40 J
The wasted energy by the machine is possibly converted to thermal energy by the frictional part of the machine.
Therefore, the work converted to thermal energy is 40 J.