Answer:
38.6 mi/h
Explanation:
7.4 mi/h = 7.4mi/h * (1/60)hour/min * (1/60) min/s = 0.00206 mi/s
Let v (mi/s) be your original speed, then the time t it takes to go 1 mi/s is
t = 1/v
Since you increase v by 0.00206 mi/s, your time decreases by 15 s, this means
t - 15 = 1/(v+0.00206)
We can substitute t = 1/v to solve for v
We can multiply both sides of the equation with v(v+0.00206)
v+0.00206 - 15v(v+0.00206) = v
v = -0.01278 or v = 0.01
0724 mi/s
Since v can only be positive we will pick v = 0.010724 mi/s or 0.010724*3600 = 38.6 mi/h
Answer:
Total heat transfer is positive
Total work transfer is positive
Explanation:
The first law of thermodynamics states that when a system interacts with its surrounding, the amount of energy gained by the system must be equal to the amount of energy lost by the surrounding. In a closed system, exchange of energy with the surrounding can be done through heat and work transfer.
Heat transfer to a system is positive and that transferred from the system is negative.
Also, work done by a system is positive while the work done on the system is negative.
Therefore, from the question, since the heat engine inputs 10kJ of heat, then heat is being transferred to the system. Hence, the sign of the total heat transfer is positive (+ve)
Also, since the heat engine outputs 5kJ of work, it implies that work is being done by the system. Hence the sign of the total work transfer is also positive (+ve).
Answer:
6.18 m/s
Explanation:
Given that a ferry approaches shore, moving north with a speed of 6.1 m/s relative to the dock. A person on the ferry walks from one side of the ferry to the other, moving east with a speed of 1.0 m/s relative to the ferry Part. What is the speed of the person relative to the dock?
The speed of the person can be calculated by using pythagorean theorem.
Let the speed of the person = S
S^2 = 6.1^2 + 1^2
S^2 = 38.21
S = sqrt ( 38.21)
S = 6.18 m/s
Therefore, the speed of the person relative to the dock is 6.18 m/s
Number of atom for each element,
Hydrogen = 2
Sulfur = 1
Oxygen = 4
