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".
Answer:
Temperature of the mixture=8 °C
Explanation:
Let, Temperature of the mixture=t °C
Q₁ = Q₂
=> m₁SΔΘ₁ = m₂SΔΘ₂
=> 39 × (20+t) = 21 × (60-t)
∴ t = 8 °C
hope you have understood this
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Answer: 1,500m/s
Explanation:
Relationship existing between velocity of a wave (v), wavelength(¶) and frequency(f) is
v = f¶... (1)
Since Frequency (f) is the reciprocal of the period (T);
Frequency = 1/Period i.e F = 1/T... (2)
Substituting equation 2 into 1 we have;
v = 1/T × ¶
v = ¶/T
Given wavelength ¶ = 9m
Period T = 0.006s
v = 9/0.006
v = 1,500m/s
The velocity of the wave will be 1,500m/s
Answer:
spring deflection is x = (v2 / R + g) m / 4
Explanation:
We will solve this problem with Newton's second law. Let's analyze the situation the car goes down a road and finds a dip (hollow) that we will assume that it has a circular shape in the lower part has the car weight, elastic force and a centripetal acceleration
Let's write the equations on the Y axis of this description
Fe - W = m 
Where Fe is elastic force, W the weight and the centripetal acceleration. The elastic force equation is
Fe = - k x
4 (k x) - mg = m v² / R
The four is because there are four springs, R is theradio of dip
We can calculate the deflection (x) of the springs
x = (m v2 / R + mg) / 4
x = (v2 / R + g) m / 4
