Explanation :
Our solar system was formed about 4.6 billion years ago. It is formed when gravity exerted low-density cloud of interstellar gas and dust. The massive cloud of gas and dust is called as Orion Nebula.
In a small area, the overdensity of clouds occurs. This caused the contraction, to begin. Due to this contraction the potential energy gets converted into kinetic energy of individual gas particles.
Hence the correct option is " materials were pulled together by the gravity". This is the one of the evidence used to indicate the beginning of the solar system.
Answer:
Option C - 39.2 J
Explanation:
We are given that;
Mass; m = 2 kg.
Distance moved off the floor;d = 10 m.
Acceleration due to gravity;g = 9.8 m/s².
We want to find the work done.
Now, the Formula for work done is given by;
Work = Force × displacement.
In this case, it's force of gravity to lift up the boots, thus;
Formula for this force is;
Force = mass x acceleration due to gravity
Force = 2 × 9.8 = 19.2 N
∴ Work done = 19.6 × 2
Work done = 39.2 J.
Hence, the Work done to life the boot of 2 kg to a height of 2 m is 39.2 J.
Answer:
Hi, Since energy levels in the nucleus are much higher than those in the gas, the nucleus will cool down by emitting a more energetic electromagnetic wave called a gamma ray . Gamma ray emission causes no change in the number of particles in the nucleus meaning both the atomic number and mass number remain the same.
Answer:
We show added energy to a system as +Q or -W
Explanation:
The first law of thermodynamics states that, in an isolated system, energy can neither be created nor be destroyed;
Energy is added to the internal energy of a system as either work energy or heat energy as follows;
ΔU = Q - W
Therefore, when energy is added as heat energy to a system, we show the energy as positive Q (+Q), when energy is added to the system in the form of work, we show the energy as minus W (-W).
