Answer:
The atmospheric pressure is
.
Explanation:
Given that,
Atmospheric pressure
drop height h'= 27.1 mm
Density of mercury 
We need to calculate the height
Using formula of pressure

Put the value into the formula



We need to calculate the new height




We need to calculate the atmospheric pressure
Using formula of atmospheric pressure

Put the value into the formula


Hence, The atmospheric pressure is
.
14 ms is required to reach the potential of 1500 V.
<u>Explanation:</u>
The current is measured as the amount of charge traveling per unit time. So the charge of electrons required for each current is determined as the product of current with time.

As two different current is passing at two different times, the net charge will be the different in current. So,

The electric voltage on the surface of cylinder can be obtained as the ratio of charge to the radius of the cylinder.

Here
, q is the charge and R is the radius. As
and R =17 cm = 0.17 m, then the voltage will be

The time is required to find to reach the voltage of 1500 V, so


So, 14 ms is required to reach the potential of 1500 V.
Answer:

Explanation:
As we know that tension force in the string will be equal to the centripetal force on the string
so we will have

now we have

now we have


now when string length is 0.896 m and its speed is 71.5 m/s then we will have



Because water is more dense than the object but rubbing alcohol is less dense than the object