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Reil [10]
2 years ago
15

Martha is late for class, so she races her 75 kg body up a 4.0 meter flight of stairs in only 2.3 seconds. What is Martha’s powe

r?
Mathematics
1 answer:
vovangra [49]2 years ago
7 0

Answer:

1.3\cdot 10^3\text{ J}

Step-by-step explanation:

Power is defined by work over time. In physics, work can be defined as the energy transferred over from an applied force over some distance. As a formula:

W=Fd, where F = force applied and d = distance that force is applied over.

*It is worth noting that F must be parallel to the distance travelled. If it is perpendicular, no work is done, and if it is at an angle, find the parallel component and use that for F.

In this case, the force applied must counter the force of gravity on Martha, which is given by F_g=mg, where m = Martha's mass and g = gravitational constant 9.8 m/s/s. Therefore, F_g=75\cdot 9.8=735\text{ N}. Since she raises her body 4.0 meters, the work done must be W=Fd=735\cdot 4=2940\text{ J}.

Since power is equal to work over time and t = 2.3 seconds, we have:

\displaystyle P=\frac{W}{t}=\frac{2940}{2.3}=\boxed{1278\text{ J}}\approx \boxed{1.3\cdot 10^3\text{ J}} (to two significant figures)

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PLEAS HELP ASAP PLEAS 20 points<br> 1 over 3b = 4 over 5. what equals b in this equation?
White raven [17]

Answer:

b = 5/12

Step-by-step explanation:

You have the proportion

1/(3b) = 4/5        

Cross multiply to get rid of the fractions...

5 = 12b                now solve for b

5/12 = b                 (divide by 12 on both sides)

8 0
3 years ago
One common factor of two numbers is 40. Another common factor is 10. If both numbers are less than 100, what are the two numbers
Viefleur [7K]
Only two numbers less than 100 have a factor of 40: 40 (1 x 40) and 80 (2 x 40). Since 40 is a factor of both 40 and 80, 10 must also be a factor - indeed, 40 = 4 x 10 and 80 = 8 x 10.

The two number must be 40 and 80.
5 0
3 years ago
Thanks, &amp; yes how did you get that
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Hello <span>Vmcdowell43

The word Thanks is a shorter way of saying Thank you. Many people use it because it is easier.

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3 years ago
If the diameter of a circle changes from 5 cm to 15 cm, how will the circumference change? A) multiplies by 1 3 B) multiplies by
andreyandreev [35.5K]
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5 0
3 years ago
Read 2 more answers
Which of the following is the inverse of the given function? Y=3x^5-4
lawyer [7]

y\textrm{ }=\textrm{ }(\frac{x\textrm{ }+\textrm{ }4}{3} )^{\frac{1}{5} }

Step-by-step explanation:

   Given function y\textrm{ }=\textrm{ }3x^{5}\textrm{ }-\textrm{ }4

   To find an inverse for any given function, which is of the form y=f(x), always swap x and y in the equation and try to get the form  x=f(y). Now, swapping back x and y, we get the inverse function.

   On swapping x and y, we get x\textrm{ }=\textrm{ }3y^{5}\textrm{ }-\textrm{ }4

y\textrm{ }+\textrm{ }4\textrm{ }=\textrm{ }3x^{5}

x^{5}\textrm{ }=\textrm{ }\frac{y\textrm{ }+\textrm{ }4}{3}

x\textrm{ }=\textrm{ }(\frac{y\textrm{ }+\textrm{ }4}{3} )^{\frac{1}{5} }

   Swapping back x and y, we get y\textrm{ }=\textrm{ }(\frac{x\textrm{ }+\textrm{ }4}{3} )^{\frac{1}{5} }

   This is the inverse function.

3 0
3 years ago
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