Power is the rate of work done given by dividing work done by time.Efficiency is the ratio of work output to work input
power input= 100 watts
power output = x
efficiency= 0.8
thus 0.8 = x/100, therefore x = 80
power is given by energy times time
hence time = 80/300000 = 0.00026 seconds
Time in hours = 0.00026/360 = 7.407 x 10 ∧7 hours
Levers
Most machines in your body are levers that consist of bones and muscles. Tendons and muscles pull on bones, making them act as levers. Joint, near where tendon is attached to bone acts as fulcrum. Muscles produce input force.
The role of a resistor in an electrical circuit is to <u>hinder the movement of charge through a circuit</u>
Explanation:
A charge is carried through a wire by current (indicated as <em>I</em> in physics S.I connotation). Higher current means the rate at which the charge is flowing through the wire is fast. High resistance of the wire means the charge flows with difficulty hence slower. Resistance is given by the formulae;
R = V/I whereby;
R = resistance
V = voltage
I = current
As you can observe <em>R</em> (resistance) is inversely proportional to<em> I </em>(current). Meaning the higher the resistance the lower the current.
