Answer:
I will answer this in English, we can translate it to:
Why if you charge a mate by an amount of time you are not doing work?
This happens because work is defined as the displacement done by a force:
W = d*F
where W is work, d is the distance, and F is the force.
This means that the amount of time that you are charging your mate does not affect the mechanical work, the only time that you are doing work is when you are lifting him.
Answer:
26000 years
Explanation:
Precession describes the angular motion of the Earth's body. Since the attitude of telescopes relative to the Earth's body can be controlled with high accuracy, and telescopes can measure the direction of incoming light also with high accuracy, the motion of Earth is under permanent high precision monitoring. Thus the basic numerical descriptor of precission, an angular rate of 5029.0966 seconds of arc per Julian century, traditionally denoted p (for precession) is a measured value from observed coordinate changes of thousands of stars over, say, two centuries. The understanding of this value in terms of forces acting on an oblate Earth from the Moon is well understood so that an extrapolation back and forth over a few full cycles contains little uncertainties. Of course, you can find details on the coordinate transformations mentioned above (the direct observational effect of precession) on the net. I was surprised to see that the Wikipedia article on precession covers the astronomical aspect very poorly. You thus better look for other sources.
Answer:
The rotor's angular velocity is 82.73rad/s
Explanation:
It is a curvilinear movement of a constant radius. If there is uniform angular acceleration, then it is a circular motion with constant acceleration, whose equations are analogous to that of the translational motion.
Calculating the initial velocity of the rotor, V1 in rad/s
V1 = 610rev/minute × 6.28 × 1miute/60secs
V1 = 63.85rad/s
Using kinematic equation to calculate the final velocity of the rotor
Given:
Angular acceleration = 5.9rad/s^2
Time,t= 3.2seconds
V2 = V1 + a × t
V2 = 63.85 + (5.9)× (3.2)
V2 = 63.85 + 18.88
V2 = 82.73rads/s
Answer:
Displacement by cyclist is zero.
Explanation:
In the given question bicyclist is travelling in a rectangular track having P , Q and R edges.
The bicyclist starts from P and travel through Q and R and returned to P again.
We need to find its displacement.
We know displacement of a body is its difference between its initial position to final position.
Here in the given question the bicyclist returns to P again.
Therefore, total displacement by bicyclist is zero.
Hence, this is the required solution.
