Thermodynamics

Physics

1 answer:

Marizza181 [45]3 years ago

5 0

Answer:

A heat engine is a device that converts internal energy into work. Internal energy is increased by the addition of heat. The efficiency of a heat engine is a measurement of how efficiently it works. Efficiency compares the amount of useful energy extracted from a process to the total energy input. The heat engine will be more efficient if the percentage is higher.

Explanation:

You might be interested in

Earth's rotational axis completes one precession every _____.

ruslelena [56]

A). Earth completes one rotation on its rotation axis
every (3 minutes and 56 seconds less than 24 hours).
This causes night and day. It's rotation, not precession.

B). Earth completes one orbital revolution around the sun
every (365 plus a little bit) days. It's revolution, not precession.

C). I'm not sure what happens on a cycle of 512 years.
It may have something to do with the moon. But whatever
it is, it's not precession.

D). When you spin a top and it starts to run down, the first
thing that happens is that the handle of the top, or the point
on top of the top, starts moving in a circle. That's precession.
That's what the Earth's axis is doing. The north pole points
toward the north star (Polaris) now. But the north pole is
actually drawing out a big circle in the sky, and other stars
will become the "north star" far in the future.
The north pole draws out a full circle in the sky, roughly
once every 26,000 years. That's precession.

6 0

3 years ago

Two workers are sliding 350 kgkg crate across the floor. One worker pushes forward on the crate with a force of 390 NN while the

svetoff [14.1K]

Answer:

$\mu_k=0.18$

Explanation:

First, we write the equations of motion for each axis. Since the crate is sliding with constant speed, its acceleration is zero. Then, we have:

$x: T+F-f_k=0\\\\y:N-mg=0$

Where T is the tension in the rope, F is the force exerted by the first worker, f_k is the frictional force, N is the normal force and mg is the weight of the crate.

Since $f_k=\mu_k N$ and $N=mg$ , we can rewrite the first equation as: