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Mandarinka [93]

3 years ago

12

A rectangular pane of glass is 91.1 cm wide and 155.9 cm long, and its area is equal to the length multiplied by the width. Usin

g the correct number of significant figures, what is the area of the glass?

2 answers:

Kamila [148]3 years ago

8 0

911.1×155.9 = 14,202.49
14,202.49 in 3 significant figures would be either 14,200 or 1.42×10^4

zlopas [31]3 years ago

8 0

Answer:

$Area = 14200 cm^2$

Explanation:

As we know that the area of the rectangle is given as

$Area = Length \times Width$

now we will have

$Length = 155.9 cm$

$Width = 91.1 cm$

here we know that significant digits in length is 4 while significant digits in width is 3.

so here we can say that Area must have three significant figures

so we will have

$Area = 155.9 \times 91.1$

$Area = 14202.49 cm^2$

so by rounding off in three significant figures the area will be

$Area = 14200 cm^2$

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3 years ago

You are riding a bicycle. If you apply a forward force of 150 N, and you and the bicycle have a combined mass of 90 kg, what wil

bekas [8.4K]

<h3>Hello There!!</h3>

<h3><u>Given</u>,</h3>

Force(F) = 150N

Mass(m) = 90kg

<h3><u>To </u><u>Find,</u></h3>

Acceleration(a) = ?

<h3><u>We know,</u></h3>

F= m×a

$150 = 90 \times \text{a} \\ \\ \text{a} = \frac{150}{90} \\ \fbox{cancelling by 3} \\ \\ \text{ a} = \cancel \frac{150}{90} \\ \\ \text{ a} = \frac{5}{3} = 1.67 \text{m/s} {}^{2}$

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3 years ago

A student team is to design a human powered submarine for a design competition. The overall length of the prototype submarine is

Allushta [10]

Answer:

a) The speed is 61.42 m/s

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a) The Reynold´s number for the model and prototype is:

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$Re_{p} =\frac{p_{p}V_{p}L_{p} }{u_{p} }$

Equaling both Reynold's number:

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$\frac{F_{Dm} }{p_{m}V_{m}^{2}L_{m}^{2} } =\frac{F_{Dp} }{p_{p}V_{p}^{2}L_{p}^{2} } \\F_{Dp} =\frac{F_{Dp}p_{p}V_{p}^{2}L_{p}^{2} }{p_{m}V_{m}^{2}L_{m}^{2} } \\F_{Dp}=\frac{2.3*999.1*0.56^{2} *8^{2} }{1.184*61.42^{2}*1^{2} } =10.32N$

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3 years ago

Read 2 more answers

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Nana76 [90]

Answer:

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Now,

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The center of mass for the cone lies at the $\frac{1}{4}$ times the total height

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W = mgh'

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alukav5142 [94]

Answer:

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4 years ago