Answer:
The Earth spins on its axis once a day.
Explanation:
In simple words,The Earth revolves on its axis once every 24 hours and circles the sun once every 365 days. The Earth's rotation on its axis, not its orbit throughout the sun causes day as well as night. The word 'one day' refers to the period it requires the Earth to spin entirely on its axis, which involves both day as well as night.
Answer:
Explanation:
The man is moving on a circular path . The reaction of wall is providing centripetal force .so
R = mv² / r
Frictional force = μR where μ is coefficient of friction
= μ x mv² / r
Frictional force = μ x mv² / r
Answer:
Explanation:
Let the radius of the hemisphere is R. The mass is released from rest so the initial speed is equal to zero and acceleration is equal to the g.
By the Newton's 3rd equation,
Now, at the bottom hemisphere the centripetal acceleration will act on the mass and the direction of this force is towards center,
Hence, the acceleration on the bottom of the hemisphere is equal to the 2g.
Viruses are microscopic organisms that exist almost everywhere on earth. They can infect animals, plants, fungi, and even bacteria.
Sometimes a virus can cause a disease so deadly that it is fatal. Other viral infections trigger no noticeable reaction.
A virus may also have one effect on one type of organism, but a different effect on another. This explains how a virus that affects a cat may not affect a dog.
Viruses vary in complexity. They consist of genetic material, RNA or DNA, surrounded by a coat of protein, lipid (fat), or glycoprotein. Viruses cannot replicate without a host, so they are classified as parasitic.
They are considered the most abundant biological entity on the planet.
