Answer:
Part 1: 0.3789
Part 2: 746 J
Part 3: 2.162 kW
Explanation:
Part 1:
Eff= 
Eff= 0.378873 ≈ 0/3789
Part 2:
W= 0.3789(1969)
W= 746 J
Part 3:

Power= 2162.3188 Watts
2162.3188 W-----> 2.162 kW
-- 1 ton is defined as 2,000 pounds.
-- 1 metric ton (or tonne) is defined as 1,000 kilograms of mass.
On Earth,1,000 kilograms of mass weigh 2,204.6 pounds ... 204.6 pounds
more than 1 ton.
On, say, the moon, however, 1,000 kilograms of mass weigh
only 364.9 pounds ... about 18% of 1 ton.
Momentum (symbol p) and the equation of momentum is:
p = m*v
Answer:
R2 = 10.31Ω
Explanation:
For two resistors in parallel you have that the equivalent resistance is:
(1)
R1 = 13 Ω
R2 = ?
The equivalent resistance of the circuit can also be calculated by using the Ohm's law:
(2)
V: emf source voltage = 23 V
I: current = 4 A
You calculate the Req by using the equation (2):

Now, you can calculate the unknown resistor R2 by using the equation (1):

hence, the resistance of the unknown resistor is 10.31Ω