Answer:
1) a block going down a slope
2) a) W = ΔU + ΔK + ΔE, b) W = ΔE, c) W = ΔK, d) ΔU = ΔK
Explanation:
In this exercise you are asked to give an example of various types of systems
1) a system where work is transformed into internal energy is a system with friction, for example a block going down a slope in this case work is done during the descent, which is transformed in part kinetic energy, in part power energy and partly internal energy that is represented by an increase in the temperature of the block.
2)
a) rolling a ball uphill
In this case we have an increase in potential energy, if there is a change in speed, the kinetic energy also increases, if the change in speed is zero, there is no change in kinetic energy and there is a change in internal energy due to the stationary rec in the point of contact
W = ΔU + ΔK + ΔE
b) in this system work is transformed into internal energy
W = ΔE
c) There is no friction here, therefore the work is transformed into kinetic energy
W = ΔK
d) if you assume that there is no friction with the air, the potential energy is transformed into kinetic energy
ΔU = ΔK
The law applied here is Newton's first law, also known as, law of inertia.
This law states that: A body will retain its state of rest or motion unless acted upon by an external force.
If you are moving and the bus suddenly stops, your body will lurch forward trying to retain its state of motion until it comes to rest and changes its state by the external force acted on it.
If you are at rest and the bus suddenly moves, your body will lurch backwards trying to retain its state of rest and opposing the force of motion until it is forced to change its state by this force.
445/100 - 5/4 = 445/100 - 125/100 = 320/100 = 16/5 = 3 1/5.
Answer:
The velocity of the frozen rock at 
is -14.711 meters per second.
Explanation:
The frozen rock experiments a free fall, which is a type of uniform accelerated motion due to gravity and air viscosity and earth's rotation effect are neglected. In this case, we need to find the final velocity (
), measured in meters per second, of the frozen rock at given instant and whose kinematic formula is:
(Eq. 1)
Where:
- Initial velocity, measured in meters per second.
- Gravity acceleration, measured in meters per square second.
- Time, measured in seconds.
If we get that 
, 
and 
, then final velocity is:
The velocity of the frozen rock at is -14.711 meters per second.
