Answer:
a) Under damped
Explanation:
Given that system is critically damped .And we have to find out the condition when gain is increased.
As we know that damping ratio given as follows

Where C is the damping coefficient and Cc is the critical damping coefficient.

So from above we can say that


From above relationship we can say when gain (K) is increases then system will become under damped system.
Answer:
d
Explanation:
is the because that's the amount of work in making machine can do producing heat
Answer:
Rate of heat transfer to the room air per meter of pipe length equals 521.99 W/m
Explanation:
Since it is given that the radiation losses from the pipe are negligible thus the only mode of heat transfer will be by convection.
We know that heat transfer by convection is given by

where,
h = heat transfer coefficient = 10.45
(free convection in air)
A = Surface Area of the pipe
Applying the given values in the above formula we get

Answer:
(a) 0 kJ
(b) 9.81 kJ
(c) 31.32 m/s
Explanation:
(a)
From the law of conservation of energy, energy can only be transformed from one state to another. At a height of 50 m, all the kinetic energy is converted to potential energy hence KE=0
(b)
Potential energy, PE=mgh where m is the mass, g is acceleration due to gravity and h is the height
Substituting 50 m for h and 20 Kg for m, taking g as 9.81 then
PE=20*9.81*50=9810 J=9.81 kJ
(c)
Relating the equation of potential energy to the equation of kinetic energy, which is 
where v is the velocity of the mass

Substituting 50 m for h and taking g as 9.81 then
