Answer: A-they change the direction of the forces
Explanation:
Any device which makes our work simpler is known as a machine. A machine may increase the amount of output force which is determined by its mechanical advantage or a machine changes the direction of the force.
In the given situation the input force acts in the downward direction to pull the rope. The output force acts on the flag being pulled upwards at the other end. Thus, the direction of the forces varies. Correct option is A.
Answer:
is the current through the body of the man.
energy dissipated.
Explanation:
Given:
- time for which the current lasted,

- potential difference between the feet,

- resistance between the feet,

<u>Now, from the Ohm's law we have:</u>


is the current through the body of the man.
<u>Energy dissipated in the body:</u>



Answer:
the velocity at point B is 27120.08 km/hr
Explanation:
check the picture attached for explanation
Answer:


Explanation:
Given:
temperature of source reservoir, 
temperature of sink reservoir, 
energy absorbed from the source, 
work done, 
a.
<u>Now change in entropy of the surrounding:</u>

<em>Since heat engine is a device that absorbs heat from a high temperature reservoir and does some work giving out heat in the universe as the byproduct.</em>



b.
<u>We know Carnot efficiency is given as:</u>



<u>Now the Carnot work done:</u>


.......................(1)
c.
From eq. (1) we have the Carnot work, so the difference:



Now, we find:

Answer:
Explanation:
To calculate an effect size, called Cohen's d , for the one-sample t-test you need to divide the mean difference by the standard deviation of the difference, as shown below. Note that, here: sd(x-mu) = sd(x) . μ is the theoretical mean against which the mean of our sample is compared (default value is mu = 0).