The correct option is C) The angle between the vectors is 120°.
Why?
We can solve the problem and find the correct option using the Law of Cosine.
Let A and B, the given two sides and R the resultant (sum),
Then,
So, using the law of cosines, we have:
Hence, we have that the angle between the vectors is 120°. The correct option is C) The angle between the vectors is 120°
Have a nice day!
Answer:
verdadero
Explanation:
Conducción:Es la más sencilla de entender, consiste en la transferencia de calor entre dos puntos de un cuerpo que se encuentran a diferente temperatura, sin que se produzca transferencia de materia entre ellos.
Mars: 0.38
weight = mass x surface gravity
multiplying your weight on Earth by the number above will give you your weight on the surface of Mars
If you weigh 150 pounds (68 kg.) on Earth, you would weigh 57 lbs. (26 kg.) on Mars
Answer:
a) The student must run flight of stairs to lose 1.00 kg of fat 709.5 times.
b) Average power
P(w)= 1062.07 [w]
P(hp)=1.42 [hp]
c) This activity is highly unpractical, because the high amount of repetitions he has to due in order to lose, just 1 Kg of fat.
Explanation:
First, lets consider the required amount of work to move the mass of the student. (considering running stairs just as a vertical movement)
Work:
Where m is the mass of the student, g is gravity (9.8 m/s) and d is the total distance going up the stairs (0.15m *85steps= 12.75m )
Converting from Joules to Kcals:
Now lets take into account the efficiency of the human body (20%)
2.537 ---> 20%
x ---> 100%
So the student is consuming 12.685 KCals each time he runs up the stairs.
Now,
1 g --> 9 Kcals
1000 g --> 9000KCals
Burning 1 g of fat, requieres 9 KCals, 1000g burns 9000KCals. So in order to burn a 1Kg of fat:
He must run up the stairs 709.5 times, to burn 1 Kg of fat.
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For b) just converting units, taking into account the time lapse. (53103.75 is the 100% of the energy in joules, from converting 12.685Kcals to joules)
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Answer:
time required is 6.72 years
Explanation:
Given data
mass m = 3.20 ✕ 10^7 kg
height h = 2.00 km = 2 × 10^3 m
power p = 2.96 kW =2.96 × 10^3 J/s
to find out
time period
solution
we know work is mass × gravity force × height
and power is work / time
so we say that power = mass gravity force × height / time
now put all value and find time period
power = mass × gravity force × height / time
2.96 × 10^3 = 3.20 ✕ 10^7 × 9.81× 2 × 10^3 / time
time = 62.784 × 10^10 / 2.96 × 10^3
time = 21.21081081 × 10^7 sec
time = 58.91891892 × 10^3 hours
time = 6.72 years
so time required is 6.72 years