Answer:
Manganese oxide prevents polarisation in dry cells. - Polarization is a defect that occurs in simple electric cells due to the accumulation of hydrogen gas around the positive electrode. ... - MnO2 reacts with H2 and forms water as byproduct, so depolarization doesn't occur.
Answer:1 because
Explanation: it’s pointing to the earth and gravity
Pulls things down to earth
<h2>
Answer: 540 J</h2>
Explanation:
The Work 
done by a Force 
refers to the release of potential energy from a body that is moved by the application of that force to overcome a resistance along a path.
Now, when the applied force is constant and the direction of the force and the direction of the movement are parallel, the equation to calculate it is:
(1)
In this case both (the force and the distance in the path) are parallel (this means they are in the same direction), so the work performed is the product of the force exerted to push the box 
by the distance traveled 
.
Hence:
(2)
Answer:
Good question to ask in physics, sir maam
Imagine you are in a swimming pool 30m deep. Assuming you know that water is denser than air, you would know that the 30m of water above you will carry more weight, and press down on your body. Say you were in a swimming pool 60m deep, you would be sandwiched between 30m of water pressing down on you, and the upthrust created by the 30m of water below you.
In a building 30m up, the pressure will be regulated, as you are in a building. The floor will be strong enough to support the weight of the body, and the body will not recoil into itself.
