Answer:
Explanation:
We can find the resistance of the wire by using Ohm's law:
where
V is the voltage applied
R is the resistance
I is the current
In this problem, we know I = 6 A and V = 68 V, so we can re-arrange the equation to find the resistance of the wire:
Answer:
Option D 3.9
Explanation:
First, you need to use the correct equation which is the following:
COP = Q/W
Where:
Q = heat absorbed
W = work done by the pump
COP = coefficient of perfomance
We have all the data, so, all you need to do is replace in the above expression and you shoould get the correct result:
COP = 30 / 7.7
COP = 3.896
This result you can round it to 3.9. option D.
0.75 kilometer= 75000 centimeters
Answer:
A car moves up a hill at a constant velocity
Explanation:
Since the velocity is constant, the speed is also constant and so is the kinetic energy. However, total mechanical energy is sum of gravitational potential energy and kinetic energy, and the car is moving up the hill so its potential energy rises.
Thus, in the circumstances described the mechanical energy cannot be conserved.
The correct answer is A car moving up the hill with constant velocity.
