C explanation: There are many examples of fossils found on separate continents and nowhere else, suggesting the continents were once joined. If Continental Drift had not occurred, the alternative explanations would be: They swam to the other continent/s in breeding pairs to establish a second population. ...
Explanation:
Work Done = Force * Displacement
= (4N)(10m) = 40J.
Power = Work Done / Time
= (40J)/(20s) = 2J/s = 2 Nm/sec.
Answer:
Explanation:
Use Archimedes' principle, that states something of this nature: "The buoyant force acting on an object immersed in a fluid is equal to the weight of the fluid displaced"
Say, you take a cube of wood(for example) and place it in a bucket of water. Your cube is bound to sink, until, the upthrust force equals its weight.
Where does this upthrust come from?
As the cube sinks, it displaced some volume of water(if the bucket were full you would see water pouring out)
Archimedes simply stated that: Upthrust,
U=mg
- Example: One way to measure the volume of any irregular object (in your case, a stone) is to submerge it completely under water and measure the change in the height of the water level. This change in the water level (let's say it goes from 50 mL to 65 mL) indicates that the stone has a volume of 15 mL.
- Example:Subtract the first volume from the second volume to calculate the volume of the stone. For example, if you recorded 40 fluid ounces the first time, and 50 fluid ounces the second time, the stone volume is 10 fluid ounces.
Answer:
A. Final pressure P2
P2/P1 = (T2/T1)^n/n-1
P1 = 4bar
T1 = 438K
T2 = 300K
Polytropic index, n, = 1.3
P2 = 4 (300/438)^1.3/1.3-1
P2 = 4 (300/438)^4.333
P2 = 4 * 0.19400
P2 = 0.776bar.
B. The work done is;
W = mR/ n-1 (T1 -T2)
Where, R = 0.1889kJ/kg.K, m = 1
W = 1 * 0.1889/ 1.3-1 * (438-300)
W = 86.89kJ/kg.
C. The heat transfer, Q
Q = W + ΔU
Q = W + mCv(T2-T1), where Cv of nitrogen is 0.743kj/kgk
Q = 86.89 + 1 * 0.743 (300-438)
Q = 86.89 + (-102.534)
Q = -15.644kJ/K
Q = 15.64kJ/K
