Kinetic energy =(1/2) (mass) (speed²)
First object: KE = (1/2) (2 kg) (2m/s)² = 4 joules during the lift.
Second object: KE = (1/2) (4kg) (3 m/s)² = 18 joules during the lift.
The second object has more kinetic energy while it's being lifted
than the first object has while it's being lifted. Once they reach their
final heights and stop, neither object has any kinetic energy.
Explanation:
If a coil of wire is placed in a magnetic field and rotated, an alternating (sinusoidal) current is induced. As it rotates, sometimes it is cutting through lots of magnetic flux, and so lots of current is
induced.
At other times, it is moving parallel to
the flux, and so no flux is cut, and no current is induced. In between, some current is induced. This creates an alternating current. Either end of the coil can be connected to wires outside of the generator in order to use the current elsewhere. This would be fine for the
first few rotations, but after this, the wires would get tangled up and the generator would be useless. To avoid this, we use a commutator. In an AC generator, this is a pair of rotating conducting 'slip rings' attached to either end of the coil. Carbon brushes bring these into contact with the outside world.
Mechanical and Chemical. (Weathering and erosion)
It might be pull at a force of 100 N. I might be wrong.
Answer:
B. Electrons are transferred from the fur to the plastic rod.
Explanation:
Triboelectricity or friction charging refers to the ability of materials to gain or lose electrons as a result of rubbing them against something. This phenomenon has been observed in the case of rubbing plastic rod against fur, or glass rod against silk.
In the context of rubbing plastic rod against fur, what happens is that the fur which has an excess of charges loses electrons to the plastic rod. This makes the plastic rod to become positively charged, and the fur, negatively charged.