Answer:
science is define as the study of physics, chemistry, biology, geology and astronomy. science is very important in our daily life.we study science for knowing the knowledge about biological and chemical and many other aspects.without science it is impossible to live our daily life.science is used in each and every steps.
Explanation:
There are many more benefits that we are getting and going to get . Science has already discovered many things ,that we didn't expect efore.And also in progress to discover new things.Science has developed a new type of antivirus that protect us from different virus.Has made different medicine that recover a people. So it is very useful in our life.
Answer:

Explanation:
Given that,
The magnitude of vector A, 
The magnitude of vector B, 
Scalar product of A and B, 
The formula for the scalar product is given by :

Where,
is the angle between A and B.

The formula for the vector product is given by :

So, the vector product between these two vectors is
.
Answer:
Photoelectric effect
Explanation:
In the photoelectric effect, when an x-ray strikes on a metal surface, the energy is completely absorbed by the metal. If the energy would be equal to or more than work function of metal, electron ejects out. The kinetic energy of the electron which is ejected depends on the energy of the incident radiation and work function of the metal.
Answer:
Answered
Explanation:
According to the impact theory, a glancing collision between a Mars-sized object and Earth led to the formation of the Moon. The iron core of Earth had formed before this collision, leading to the similarity between the composition of the Moon and Earth's mantle. After the collision, any iron core of the Mars-sized object would have been left behind on Earth and eventually merged with Earth's core. The Moon then formed out of the debris thrown into space by the collision.
Answer: in a medium
Explanation:
Mechanical waves require medium to transfer energy. The medium particles vibrate about their fixed position to transfer energy. There is no transport of medium particles.
Example, sound waves are mechanical waves. The sound travels through compression and rarefaction of the medium particles.