Answer:
118 N
Explanation:
Given mass of the block, m = 4.00kg.
The acceleration of the elevator, a = 3.0 m/s^2.
As elevotar attaced with spring scale and accelerating upward
(block and elevator), so total force
Here, mg is the weight of the block downward direction.
or
substitute the given value, we get
= 117.6 N = 118 N.
Thus, the reading on the spring scale to 3 significant figures is 118 N.
Answer:
Energy cannot be changed from one form to another without a loss of usable energy
Explanation:
Second law of thermodynamics states that the total entropy or the randomness of the system remains constant over time. It also states that the net entropy will remain the same or it will increase.
Entropy of a system is given by heat absorbed divided by temperature. It is given by :
So, the correct option is (A) "Energy cannot be changed from one form to another without a loss of usable energy".