Efficiency η of a Carnot engine is defined to be:
<span>η = 1 - Tc / Th = (Th - Tc) / Th </span>
<span>where </span>
<span>Tc is the absolute temperature of the cold reservoir, and </span>
<span>Th is the absolute temperature of the hot reservoir. </span>
<span>In this case, given is η=22% and Th - Tc = 75K </span>
<span>Notice that although temperature difference is given in °C it has same numerical value in Kelvins because magnitude of the degree Celsius is exactly equal to that of the Kelvin (the difference between two scales is only in their starting points). </span>
<span>Th = (Th - Tc) / η </span>
<span>Th = 75 / 0.22 = 341 K (rounded to closest number) </span>
<span>Tc = Th - 75 = 266 K </span>
<span>Lower temperature is Tc = 266 K </span>
<span>Higher temperature is Th = 341 K</span>
Explanation:
<em>Light</em><em> </em><em>is</em><em> </em><em>a</em><em> </em><em>form</em><em> </em><em>of</em><em> </em><em>energy</em><em> </em><em>that</em><em> </em><em>travels</em><em> </em><em>as</em><em> </em><em>waves</em><em>.</em>
Answer:
a) 4.0 rad/s2
Explanation:
- For rigid bodies, Newton's 2nd law becomes :
τ = I * α (1)
where τ is the net external torque applied, I is the rotational inertia
of the body with respect to the axis of rotation, and α is the angular
acceleration caused by the torque.
- At the same time, we can apply the definition of torque to the left side of (1), as follows:

where τ = external net torque applied by Fnet, r is the distance
between the axis of rotation and the line of Fnet, and θ is the
angle between both vectors.
In this particular case, as Fnet is applied tangentially to the disk, Fnet
and r are perpendicular each other.
- Since left sides of (1) and (2) are equal each other, right sides are equal too, so we can solve for the angular acceleration as follows: