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3 years ago

5

An engine that has an efficiency of 25% takes in 200 [J] of heat during each cycle. Calculate the amount of work this engine per

forms.

1 answer:

BartSMP [9]3 years ago

5 0

Answer:

$W=50J$

Explanation:

The work done $W$ and the energy taken $Q_{in}$ by a heat engine are related to the efficiency $\eta$ by the expression

$\eta=\frac{W}{Q_{in}}$

The efficiency is $\eta$ =25%, the numerical form of this percentage is 0.25 and the energy taken is $Q_{in}$ =200J. Replacing in the formula:

$0.25=\frac{W}{200}\\W=200*0.25\\W=50J$

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Mashcka [7]

Answer:

The slope of a position-time graph can be calculated as:

$m=\frac{\Delta y}{\Delta x}$

where

$\Delta y$ is the increment in the y-variable

$\Delta x$ is the increment in the x-variable

We can verify that the slope of this graph is actually equal to the velocity. In fact:

$\Delta y$ corresponds to the change in position, so it is the displacement, $\Delta s$

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which corresponds to the definition of velocity.

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3 years ago

An experiment is done to compare the initial speed of projectiles fired from high-performance catapults. The catapults are place

anzhelika [568]

Answer:1.084

Explanation:

Given

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mass of bullet m=5.5 gm

velocity of bullet u

After collision let say velocity is v

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$v=\frac{m}{M+m}\times u$

Conserving Energy for Pendulum

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$\frac{(M+m)v^2}{2}=(M+m)gh$

here $h=L(1-\cos \theta )$ from diagram

therefore

$v=\sqrt{2gL(1-\cos \theta )}$

initial velocity in terms of v

$u=\frac{M+m}{m}\times \sqrt{2gL(1-\cos \theta )}$

For first case $\theta =6.8^{\circ}$

$u_1=\frac{M+m_1}{m_1}\times \sqrt{2gL(1-\cos 6.8)}$

for second case $\theta =11.4^{\circ}$

$u_2=\frac{M+m_2}{m_2}\times \sqrt{2gL(1-\cos 11.4)}$

Therefore $\frac{u_1}{u_2}=\frac{\frac{M+m_1}{m_1}\times \sqrt{2gL(1-\cos 6.8)}}{\frac{M+m_2}{m_2}\times \sqrt{2gL(1-\cos 11.4)}}$

$\frac{u_1}{u_2}=\frac{1819.181\times 0.0838}{1001\times 0.1404}$

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3 years ago

Which formula describes acceleration?<br><br> m/s^2<br><br><br> m/s<br><br><br> s/m<br><br><br> m2

Aleks04 [339]

Answer:

m/s^2

Explanation:

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kgm/s^2 = kg × acceleration

where acceleration = Force ÷ mass

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3 years ago

28. Ken and Musa shared a cake such that Ken got twice the size

ratelena [41]

Answer:

$Musa = \frac{1}{3}$

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Required

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Factorize

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3 years ago

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Margaret [11]

The answer for apex is ibn al-haytham.

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3 years ago