Answer:
A: Copper is a good conductor
Explanation:
For an electrical current to flow through something, the main power source has to fight against the resistivity. Copper wire has a very low level of resistivity making it an excellent conductor. Basically, copper is super bendy and flexible, electricity.
Fun fact, sinc humans are also super bendy and essentially big sacs of all things wet and watery, we're considered to also be excellent conductors. We also have very intricate circuitry and a lot of natural electricity so basically, we were made for it, especially since the body already used little bits of electricity to function.
Answer:
C. There is a net horizontal force on the skier in the direction the boat’s velocity.
Explanation:
This is because, according to Newton's First law of motion, when an object which in this case is the skier tends to be in equilibrium because it travels at a constant velocity, there is no net acceleration of the skier, and this causes the net force on the skier to be equal to zero.
Therefore in this question, option C which states that "There is a net horizontal force on the skier in the direction the boat’s velocity" is a false statement.
The kinetic energy of an object is given by

where m is the mass of the object and v its velocity.
For the car in the problem,

and

, so the kinetic energy of the car is

and as we can see, yes, the answer depends on the car's mass.
Answer:
false
Explanation:
Even small environmental changes have large effects because small things become bigger
Answer:
0.6375 m/s
Explanation:
Let x be the distance of the man from the building
from the figure attached
initially the value of x=12
Given:

where the negative sign depicts that the distance of the man from the building is decreasing.
Now, Let The length of the shadow be = y
we have to calculate
when x=4
from the similar triangles
we have,
or

Differentiating with respect to time 't' we get

or

Now for x = 4, and
we have,

or

<u>here, the negative sign depicts the decrease in length and in the question it is asked the decreasing rate thus, the answer is </u><u>0.6375m/s</u>