Diagram 4 is the correct answer.
1 horsepower is equal to 746 W, so the power of the engine is

The power is also defined as the energy E per unit of time t:

Where the energy corresponds to the work done by the engine, which is

. Re-arranging the formula, we can calculate the time t needed to do this amount of work:
The Average velocity for the bacterium is 0.75 unit/sec.
<u>Explanation:</u>
The given values are in the vector form
Where,
dS = distance covered
dT = time interval
Now, to calculate distance covered, we have

&

d S=(4.6 i+1.9 k)-(2.2 i+3.7 j - 1.2 k)
d S=(4.6-2.2) i+(0-3.7) j+(1.9+1.2) k
d S=2.4 i-3.7 j+3.1 k
Now, putting these values in the standard formula to evaluate the average velocity, we get;


As dT=7.2 sec
Now,
Solving the equation, we get;


Hence, the average velocity for the bacterium is 0.75 unit/sec.
Answer:
7.24 Ω
Explanation:
Power = energy / time = 195 J / 9.81 = 19.88 W
and power = V² / R
R resistance = 12 V² / 19.88 W = 7.24 Ω