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2 years ago

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A square solar collector measures 6.00 m by 6.00 m and another solar collector measures 8.000 m by 8.000 m. using the correct nu

mber of significant figures what is the combined area of both collectors?
a) 1.00×10^2
b) 1.0 ×10^2
c)1×10^2
d) 1.000x10^2
e) 1.0000x10^2

1 answer:

Vlad1618 [11]2 years ago

7 0

Answer: $1.000\times 10^2m^2$

Explanation:

Significant figures : The figures in a number which express the value -the magnitude of a quantity to a specific degree of accuracy is known as significant digits.

The rule apply for the multiplication and division is :

The least precise number present determines the number of significant figures in the answer.

The rule apply for the addition and subtraction is :

The least precise number present after the decimal point determines the number of significant figures in the answer.

Area of square collector 1 =

Area of square collector 1 = $6.00m\times 6.00m=36.0m^2$

Area of square collector 2 = $length\times breadth$

Area of square collector 2 = $8.000m\times 8.000m=64.00m^2$

Combined area of both collectors = Area of square collector 1 + Area of square collector 2 = $36.0m^2+64.00m^2=100.0m^2=1.0\times 10^2m^2$

The combined area of both collectors is $1.000\times 10^2m^2$

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<em></em>

Explanation:

The complete question is

A flywheel is a mechanical device used to store rotational kinetic energy for later use. Consider a flywheel in the form of a uniform solid cylinder rotating around its axis, with moment of inertia I = 1/2 mr2.

Part (a) If such a flywheel of radius r1 = 1.1 m and mass m1 = 11 kg can spin at a maximum speed of v = 35 m/s at its rim, calculate the maximum amount of energy, in joules, that this flywheel can store?

Part (b) Consider a scenario in which the flywheel described in part (a) (r1 = 1.1 m, mass m1 = 11 kg, v = 35 m/s at the rim) is spinning freely at its maximum speed, when a second flywheel of radius r2 = 2.8 m and mass m2 = 16 kg is coaxially dropped from rest onto it and sticks to it, so that they then rotate together as a single body. Calculate the energy, in joules, that is now stored in the wheel?

Part (c) Return now to the flywheel of part (a), with mass m1, radius r1, and speed v at its rim. Imagine the flywheel delivers one third of its stored kinetic energy to car, initially at rest, leaving it with a speed vcar. Enter an expression for the mass of the car, in terms of the quantities defined here.

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$I$ = $\frac{1}{2}$ $mr^{2}$

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<em></em>

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<em></em>

<em></em>

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2 years ago