Answer:
<em>The new period of oscillation is D) 3.0 T</em>
Explanation:
<u>Simple Pendulum</u>
A simple pendulum is a mechanical arrangement that describes periodic motion. The simple pendulum is made of a small bob of mass 'm' suspended by a thin inextensible string.
The period of a simple pendulum is given by

Where L is its length and g is the local acceleration of gravity.
If the length of the pendulum was increased to 9 times (L'=9L), the new period of oscillation will be:


Taking out the square root of 9 (3):

Substituting the original T:

The new period of oscillation is D) 3.0 T
Explanation:
the correct answer is the last one
Answer:
a) 
b) 
Explanation:
Given:
- mass of copper,

- initial temperature of copper,

- specific heat capacity of copper,

- mass of water,

- initial temperature of water,

- specific heat capacity of water,

a)
<u>∵No heat is lost in the environment and the heat is transferred only between the two bodies:</u>
Heat rejected by the copper = heat absorbed by the water


b)
<u>Now the amount of heat transfer:</u>



∴Entropy change


