Answer:
The change in potential energy of the mass as it goes up the incline is 0.343 joules.
Explanation:
We must remember in this case that change in the potential energy is entirely represented by the change in the gravitational potential energy. From Work-Energy Theorem and definition of work we get that:

Where:
- Gravitational potential energy, measured in Joules.
- Mass, measured in kilograms.
- Gravitational acceleration, measured in meters per square second.
- Change in vertical height, measured in meters.
This work is the energy needed to counteract effects of gravity at given vertical displacement.
If we know that
,
and
, the change in the potential energy of the mass as it goes up the incline is:


The change in potential energy of the mass as it goes up the incline is 0.343 joules.
Answer:
The early observations in Astronomy were used to determine the length of the year and to determine the seasons, which is an important factor in knowing when plants will grow. In the early days, astronomy consisted only of observations and projections of objects that could be seen by ordinary eyes.
Explanation:
Astronomy is the oldest of the modern natural sciences. It probably came with the need for a calendar. In ancient times, astronomers were monks, shamans, druids, and priests. At that time, astronomy was considered astrological. In some places, early civilizations have created great spaces for some astronomical purposes. In addition to rituals, these early observations were used to determine the length of the year and to determine the seasons, which is an important factor in knowing when plants will grow. In the early days, astronomy consisted only of observations and projections of objects that could be seen by ordinary eyes. According to some estimates, Stonheng, the Ziggurats in Mesopotamia, and the Pyramids of the Stones and the Chinese are the oldest observatory. Moon calendars are still considered very accurate today. Similarly, Chinese star catalogs are a valuable source for studying ancient astronomical events. Greek scholars made a special contribution to the development of astronomy. Aristotle, Ptolemy, Hipparchus, Fales, Aratos were engaged in astronomy along with other scientific discoveries. Ptolemy has developed the Geocentric Theory to explain the planetary movement of planets. According to this theory, the earth remains stationary in the center of the world, and all the celestial bodies revolve around it. Ptolemy commented regularly on Almagest. The training continued until the 16th century. Despite religious resistance, this training has been replaced by training in the world's heliocentric system. It is thought that the 6,500-year-old megaliths (Nabta Playa, Stonehenge), planted by ancient people, were used for astronomical observation. In the Rig Veda, there are 27 constellations and 13 separate constellations associated with the movement of the sun. The most important contribution made by ancient Greeks to astrology is that they have tried to classify stars according to their size.
Answer:
D
Explanation:
The rubber rod having been rubbed with fur get a net negative charge thereby gaining more mass which means the mass has increased compared to before it was rubbed against the fur while the glass rod having been rubbed with the silk to give it a net positive has lost mass and therefore has less mass compared to before it was rubbed on the silk.
Answer:
a) F = 21.16 N, b) a = 3.17 10²⁸ m / s
Explanation:
a) The outside between the alpha particles is the electric force, given by Coulomb's law
F =
in that case the two charges are of equal magnitude
q₁ = q₂ = 2q
let's calculate
F =
F = 21.16 N
this force is repulsive because the charges are of the same sign
b) what is the initial acceleration
F = ma
a = F / m
a =
21.16 / 4.0025 1.67 10-27
a = 3.17 10²⁸ m / s
this acceleration is in the direction of moving away the alpha particles
The circuit component the symbol represents is: C) Battery