Answer:
b) The isolated system stores 80 J of total energy, but it is converted to a different form of energy.
Explanation:
The Law of Conservation of Energy states that in an isolated system the total energy always remains constant. In our context this means that the box's energy cannot disappear from the isolated system of the box, slide, and the earth. Abiding the Law of Conservation of Energy, as the box slides down the friction-less table, its gravitational potential energy is converted into its kinetic energy.
Thus, in accord with the Law of Conservation of Energy, the energy of the system can neither decrease or increase, but is converted from one from to another. This rules of choices A, B, and C, leaving only choice B as correct.
Answer:
ft
Explanation:
First we will determine the acceleration of the bus while it is moving upward
The equilibrium equation would be
Let the displacement be 
As per newton's third law of motion
Answer: e. P/2
Explanation:
For ideal gases, we have the relation:
P*V = n*R*T
where:
n = number of mols
R = Gas constant
T = temperature
V = volume
P = pressure.
We know that for sample A, we have n moles, a temperature T and a volume V, then the pressure of this sample will be:
Pa = (n*R*T)/V.
For sample B, we have:
n/2 moles, temperature T/2 and a volume V/2, then the pressure will be:
Pb = (n/2)*R*(T/2)*(2/V) = (n*R*T/V)*(2/4)
and:
(n*R*T/V) = Pa
Then we can replace it and we get:
Pb = (n*R*T/V)*(2/4) = Pa*(2/4) = Pa*(1/2) = Pa/2.
Then the correct option is e.
Answer:
The nest must be about 4.15 meters above ground
Explanation:
Use the velocity equation under accelerated motion (acceleration of gravity ):
which for this case has initial velocity = 0 (falls from the nest), final velocity = 9 m/s, and a = 9.8 m/s^2, then we can find the time needed in air while falling to reach the required speed:
We now use this time value to find the distance covered in free fall during 0.92 seconds:
