B is the right answer. Multiply numbers you get the answer
The moon orbiting the Earth
Explanation:
The motion of the moon orbiting the earth is a circular motion. Circular motion is simply the motion of an object in circle at constant speed.
- A cannonball flying from a cannon is a projectile motion and not a circular motion.
- A car moving along a straight track is a linear/translational motion.
- Pendulum of a grandfather clock is a simple harmonic motion.
Learn more:
Circular motion brainly.com/question/2562955
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Answer:
0.20
Explanation:
The box is moving at constant velocity, which means that its acceleration is zero; so, the net force acting on the box is zero as well.
There are two forces acting in the horizontal direction:
- The pushing force: F = 99 N, forward
- The frictional force:
, backward, with
coefficient of kinetic friction
m = 50 kg mass of the box
g = 9.8 m/s^2 gravitational acceleration
The net force must be zero, so we have

which we can solve to find the coefficient of kinetic friction:

The thermal efficiency is defined as follows

,
and the energy which is put into the system is

.
In your case

So

which gives an efficiency of

.