<span>The answer is B. It can be converted from high to low voltage and vice versa using transformers. That is why high voltages (tens or hundreds of kilovolts) is used to efficiently transfer electricity for large distances and then converted to 110-240V.
The answer can also be derived by elimination. [A] is not right because battery provides only Direct Current (DC). [C] is not right because high voltages are used for AC (from 110V to hundreds of kilovolts). [D] is not right because as the name Alternating Current suggests, the current is alternating in its direction. [E] is not right because DC was the first type of current invented.</span>
Answer:The correct options are:
1. A system is a group of objects analyzed as one unit.
2. Energy that moves across system boundaries is conserved.
Explanation:
A system is defined as group of interrelated or interacting items existing as a single unit or a whole to achieve a specific objective.Energy lost by the system is equal to the energy gained by the surroundings.
Two statements are true about a system:
- A system is a group of objects analyzed as one unit.
- Energy that moves across system boundaries is conserved.
Answer:
(A) 3.1 m/s
(B) 2.0 s
Explanation:
At the minimum speed, the force of gravity equals the centripetal force.
mg = m v² / r
v = √(gr)
v = √(9.8 m/s² × 1.0 m)
v = 3.1 m/s
The time is the circumference divided by the speed.
t = (2π × 1.0 m) / (3.1 m/s)
t = 2.0 s
Answer:
For the first one its about 25 feet
Explanation:
Answer:

Explanation:
Given two mass on an incline code
and
and an angle of inclination
.
. Assume that
is the weight being pulled up and
the hanging weight.
-The equations of motion from Newton's Second Law are:
where a is the acceleration.
#Substituting for
(tension) gives:

#and solving for 
which is the system's acceleration.