Answer:
a.)
I.) Open system
II.) Closed system
b.)
The total momentum of the object and earth system stay the same as the object fall toward the earth
The kinetic energy of the object increases as the object falls toward the earth.
Explanation:
a.)
I.) The system containing only the object is an open system because of the influence of external forces and presence of matters. External forces in this scenario means gravitational force acting on the object. And air is the matter that has influence on the object.
II.) The system containing only the object and earth is a closed system. Because in a closed system, there are no external dissipative forces acting on it. Universe is a closed system. And the mechanical energy of a close system is conserved. The mechanical energy will remain constant. In other words, it will not change (become more or less). This is called the Law of Conservation of Mechanical Energy.
b.) The total momentum of the object and earth system stay the same as the object fall toward the earth. Because momentum will always be conserved.
The kinetic energy of the object increases as the object falls toward the earth. When the object was initially at rest, kinetic energy equals zero
Answer:
Part a)
k = 588.6 N/m
Part b)
v = 0.7 m/s
Explanation:
As we know that initially block is at rest
now if block is released from rest then it will go down by 10 cm and again comes to rest
so here we have
Part a)
Work done by gravity + work done by spring force = change in kinetic energy




Part b)
Now when spring is stretch by x = 5 cm then the speed of the block is given as

here we have




Answer:
After power is generated at a power plant, its voltage is increased by a step-up transformer. The power then travels through transmission lines to a neighborhood where it will run homes, offices, and factories. But before entering the neighborhood, the power's voltage is decreased by a step-down transformer
Transformers can be used either to increase the voltage (called "stepping up") or decrease the voltage ("step down"). When electrical energy travels long distances in wires, some of the energy is lost. ... Later, the voltage is stepped down before it enters your home - once again using transformers
Answer:
a) t = 0.75 s, b) t = 2.25 s
Explanation:
The speed of sound is constant in a material medium
v = 340 m / s
we can use the relations of uniform motion to find the time
v = x / t
t = x / v
In the exercise, the observer's distance to the wall is indicated d = 510 m, it also indicates that the shot is fired at the midpoint
x = d / 2
a) direct sound the distance from the observer to the screen is
x = 510/2 = 255 m
t = 255/340
t = 0.75 s
b) echo sound.
In this case the sound reaches the wall bounces, the distance is
x = d / 2 + d
x = 3/2 d
x = 3/2 510
x = 765 m
the time is
t = x / v
t = 765/340
t = 2.25 s
Answer:
Sedimentary
Explanation:
The process by which rock fragments are moved from the source is Sedimentary.