Explanation:
It is given that,
Mass of the ball, m = 1 lb
Length of the string, l = r = 2 ft
Speed of motion, v = 10 ft/s
(a) The net tension in the string when the ball is at the top of the circle is given by :
F = 18 N
(b) The net tension in the string when the ball is at the bottom of the circle is given by :
F = 82 N
(c) Let h is the height where the ball at certain time from the top. So,
Since,
Hence, this is the required solution.
Heat engines were developed during industrial revolution.
Generally a heat engine contains three parts i.e source, sink and working substance.
The source of a heat engine is present at a higher temperature as compared to the sink. Due to the temperature difference, the heat will flow from source to sink through working substance.
Let us consider are the temperature of source and sink.
As the source is at higher temperature as compared to sink, heat will flow from source to sink.
are the heat provided by source and heat rejected to sink.
Hence, the work done by the working substance will be -
The efficiency of a heat engine is defined as the ratio of output to the input energy.
Here output = workdone [W]
Hence, the efficiency of a heat engine is calculated as -
This is the expression for the efficiency of heat engine.
Here, all the heat absorbed by the working substance can not be converted to desired output. The efficiency of a heat engine can not be 100 percent. Some amount of heat is lost in the form of sound and heat due to the friction which is produced due to the relative motion between various parts of the machine.
One of the fundamental pillars to solve this problem is the use of thermodynamic tables to be able to find the values of the specific volume of saturated liquid and evaporation. We will be guided by the table B.7.1 'Saturated Methane' from which we will obtain the properties of this gas at the given temperature. Later considering the isobaric process we will calculate with that volume the properties in state two. Finally we will calculate the times through the differences of the temperatures and reasons of change of heat.
Table B.7.1: Saturated Methane
Calculate the specific volume of the methane at state 1
Assume the tank is rigid, specific volume remains constant
Now from the same table we can obtain the properties,
At
We can calculate the time taken for the methane to become a single phase
Here
Initial temperature of Methane
Warming rate
Replacing
Therefore the time taken for the methane to become a single phase is 5hr