2265 helium-filled balloons will be needed to lift a person whose mass is 70 kg.
Bouyancy, also known as upthrust, is an upward force applied by a fluid against the weight of an object that is partially or completely submerged. According to Achimede's principle, a force acts in opposition to an object's weight; if the force is higher than the object's weight, the object will float, but if the force is less than the object's weight, the object will sink. As a result, the helium balloon's weight must be more than the man's weight in order to lift him.
Vm = 30L
Mass = 70kg
Air density = 1.20kg/m^3
Helium density = 0.17kg/m^3
Overall density = Air density - Helium density
= 1.20 - 0.17
= 1.03kg/m^3
Convert the overall density to kg/liter
1.03/1000
0.00103kg/liter
Force on balloon
F = Overall density × vm
= 0.00103 × 30
= 0.0309kgf
Number of ballons is
70kgf/ 0.0309kgf
= 2265.37 ballons
=2265 ballons
To learn more about Achimede's principle. Click, brainly.com/question/787619
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Level 1: Plants and algae make their own food and are called producers. Level 2: Herbivores eat plants and are called primary consumers.
Answer:
D is the correct answer for this question.
Explanation:
I had done this already
2e min :)) pls park braliest
Answer:
The resistance for the second resistor is R2 = 240 Ohms and the equivalent resistance is Requivalent = 280 Ohms.
Explanation:
The resistance of a ohmic resistor is influeced by the type of it's material and by the it's construction. The longer the wire the greater the resistance and the greater the cross-sectional the lower the resistance. This can be expressed by the following equation:
R = (p*L)/A
Where p is a constant for the material of the resistor, L is the length of the wire and A is the area of the cross-sectional. In our case we have a resistor R1 that has a resistance of 40 Ohms, while a second resistor R2 made with the same material but with double length and half cross sectional. If we say that R1 is:
R1 = (p*L)/A
Then R2 must be:
R2 = (p*3*L)/(A/2)
Because the only things that changed were the length and area of the cross-sectional. We can now relate both resistors to find the second resistance, using the equation for R2. So we have:
R2 = [3*(p*L)/A]*2 = 6*(p*L)/A = 6*R1
We know that R1 is 40 Ohms so R2 = 6*40 = 240 Ohms.
The equivalent resistance of a series connection is the sum of the individual resistances, so we have:
Requivalent = R1 + R2 = 40 + 240 = 280 Ohms.