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Black_prince [1.1K]
3 years ago
12

A teacher pushed a 98 newton desk across a floor for a distance of 5 meters. He exerted a horizontal force of 20 N for four seco

nds. What was his power?
Physics
1 answer:
Pie3 years ago
7 0

Answer:

First let's find the work.

Work = Force*Displacement

= 20*5

= 100 Joules

Power = Work/Time

= 100/4

= 25 Watts

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Blood pressure is usually measured by wrapping a closed air-filled jacket equipped with a pressure gage around the upper arm of
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Answer:

a) High and low pressures are 15.999 kilopascals and 10.666 kilopascals, respectively.

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Explanation:

a) <em>High and low pressures in kilopascals</em>:

101.325 kPa equals 760 mm Hg, then, we can obtain the values by a single conversion:

p_{high} = 120\,mm\,Hg\times \frac{101.325\,kPa}{760\,mm\,Hg}

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\frac{h_{w}}{h_{Hg}} = \frac{\rho_{Hg}}{\rho_{w}}

h_{w} = \frac{\rho_{Hg}}{\rho_{w}}\times h_{Hg} (Eq. 1)

Where:

\rho_{w}, \rho_{Hg} - Densities of water and mercury, measured in kilograms per cubic meter.

h_{w}, h_{Hg} - Heights of water and mercury columns, measured in meters.

If we know that \rho_{w} = 1000\,\frac{kg}{m^{3}}, \rho_{Hg} = 13600\,\frac{kg}{m^{3}}, h_{Hg, high} = 0.120\,m and h_{Hg, low} = 0.080\,m, then we get that:

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h_{w, low} = \frac{13600\,\frac{kg}{m^{3}} }{1000\,\frac{kg}{m^{3}} } \times 0.080\,m

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