Answer:
Number of days needed = 57
Explanation:
Depth of well = 115 feet
Distance traveled in day = 3 feet up
Distance traveled in night = 1 feet down.
Total displacement in 1 day = 3 - 1 = 2 feet up
When the snail reaches 112 feet up, the next 3 feet up motion on day will make it reach the top.

After 56 days the displacement of snail is 112 feet.
On the next day it moves up by 3 feet and reaches out of well.
Number of days needed = 57
Answer: A glass object receives a positive charge of +3 nC by rubbing it with a silk cloth. In the rubbing process electrons been removed from it.
Explanation:
It is known that for every atom the protons and neutrons reside in the nucleus of the atom. Whereas electrons move outside the nucleus of an atom. As a result, electrons are able to transfer more easily from one substance to another as compared to the protons.
This is because protons are tightly held by the nucleus of an atom. Whereas electrons are mobile in nature and hence, they can easily move.
Therefore, positive charge on the glass develops due to the removal of electrons from it.
thus, we can conclude that in the given process electrons been removed from the glass object.
Answer:

Explanation:
As we know that here final equilibrium temperature is 0 degree C
so we can use energy conservation here
heat given by the cube = heat absorbed by the ice
so we have

so here we have



Answer:
θ = 41.8º
Explanation:
This is an internal total reflection exercise, the equation that describes this process is
sin θ = n₂ / n₁
where n₂ is the index of the incident medium and n₁ the other medium must be met n₁> n₂
θ = sin⁻¹ n₂ / n₁
let's calculate
θ = sin⁻¹ (1.00 / 1.50)
θ = 41.8º