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3 years ago

14

Anyone know this... pls help its for a grade

1 answer:

hodyreva [135]3 years ago

3 0

His average speed is 45 miles an hour

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A friction force of 280 N exists between a cart and the path. If the force of reaction is 766 N, what is the minimum action forc

MatroZZZ [7]

force of friction on the cart is given as

$F_f = 280 N$

here we also know the reaction force due to surface

$R = 766 N$

so we can say reaction force is given as

$R = \sqrt{F_n^2 + F_f^2}$

$766 = \sqrt{F_n^2 + 280^2}$

$F_n^2 = 766^2 - 280^2$

$F_n = 713 N$

now by force balance we will say

$F_y + F_n = mg$

$F_y = mg - F_n$

$F_x = F_f$

also we know that

$F_f = \mu * F_n$

$280 = \mu * 713$

$\mu = 0.39$

now minimum force required to set this into motion

$F_{min} = \frac{\mu mg}{\sqrt{1 + \mu^2}}$

here we know that

$mg = F_n = 713 N$

$F_{min} = \frac{0.39* 713}{\sqrt{1 + 0.39^2}}$

$F_{min} = 259 N$

So it will require 259 N minimum force to move it

3 0

3 years ago

The temperature scale which starts at absolute zero is the _____.

oksian1 [2.3K]

The temperature scale which starts at absolute zero is the Kelvin scale. The correct option in respect to the given question is the last option. William Thompson was the British scientist and inventor that invented the Kelvin scale. William Thompson was also popularly known as Lord Kelvin.His discovery of the Kelvin scale is considered one among the three best scales in use for measuring temperatures.Each measuring unit of this scale is never called a degree but a Kelvin. This specialized scale gives the option of measuring temperature in both centigrade and Fahrenheit.

6 0

3 years ago

Read 2 more answers

A cylinder which is in a horizontal position contains an unknown noble gas at 4.63 × 104 Pa and is sealed with a massless piston

AleksandrR [38]

Answer:

The change in internal energy of the system is -17746.78 J

Explanation:

Given that,

Pressure $P=4.63\times10^{4}\ Pa$

Remove heat $\Delta U= -1.95\times10^{4}\ J$

Radius = 0.272 m

Distance d = 0.163 m

We need to calculate the internal energy

Using thermodynamics first equation

$dU=Q-W$ ...(I)

Where, dU = internal energy

Q = heat

W = work done

Put the value of W in equation (I)

$dU=Q-PdV$

Where, W = PdV

Put the value in the equation

$dU=-1.95\times10^{4}-(4.63\times10^{4}\times3.14\times(0.272)^2\times(-0.163))$

$dU=-17746.78\ J$

Hence, The change in internal energy of the system is -17746.78 J

3 0

3 years ago

The largest tendon in the body, the Achilles tendon, connects the calf muscle to the heel bone of the foot. This tendon is typic

tia_tia [17]

Answer:

Tension on tendon = 1669800N

Explanation:

Detailed explanation and calculation is shown in the image below

7 0

3 years ago

Lauren throws her first pitch of the season for her school's softball team. If the ball travels 80 feet and takes 1.58 seconds t

kow [346]

Answer:

<em><u>5</u></em><em><u>0</u></em><em><u>.</u></em><em><u>6</u></em><em><u>3</u></em><em><u> </u></em><em><u>f</u></em><em><u>t</u></em><em><u>/</u></em><em><u>s</u></em><em><u> </u></em><em><u>(</u></em><em><u>2</u></em><em><u>d</u></em><em><u>p</u></em><em><u>)</u></em>

Explanation:

Speed = Distance/Time

80/1.58 = 50.63291139

= <u>50.63</u><u> </u><u>f</u><u>t</u><u>/</u><u>s</u> (2dp)

6 0

2 years ago