<span>when it returns to its original level after encountering air resistance, its kinetic energy is
decreased.
In fact, part of the energy has been dissipated due to the air resistance.
The mechanical energy of the ball as it starts the motion is:
</span>

<span>where K is the kinetic energy, and where there is no potential energy since we use the initial height of the ball as reference level.
If there is no air resistance, this total energy is conserved, therefore when the ball returns to its original height, the kinetic energy will still be 100 J. However, because of the presence of the air resistance, the total mechanical energy is not conserved, and part of the total energy of the ball has been dissipated through the air. Therefore, when the ball returns to its original level, the kinetic energy will be less than 100 J.</span>
Answer:
Explanation:
A. Using
Sinစ= y/ L = 0.013/2.7= 0.00481
စ=0.28°
B.here we use
Alpha= πsinစa/lambda
= π x (0.0351)sin(0.28)/588E-9m
= 9.1*10^-2rad
C.we use
I(စ)/Im= (sin alpha/alpha) ²
So
{= (sin0.091/0.091)²
= 3*10^-4
Answer:

Explanation:
<u>Given:</u>
- Mass,
- Velocity,

where,
are the uncertainties in mass and velocity respectively.
The kinetic energy is given by

The uncertainty in kinetic energy is given as:

Answer:
Option C
Explanation:
Kinetic energy is the energy that the body possesses by virtue of its motion.
The formula for Kinetic energy is given by 
Using this formula let us find kinetic energy for the bodies given and find out which is the greatest
A) KE = 
B) KE =
C) KE = 
D) KE = 
Comparing these we find that 9mv^2 is the highest.
Hence option C is the answer.
Answer:
<u>B. the stars of spectral type A and F are considered reasonably to have habitable planets but much less likely to have planets with complex plant - or animal - like life.</u>
Explanation:
The appropriate spectral range for habitable stars is considered to be "late F" or "G", to "mid-K" or even late "A". <em>This corresponds to temperatures of a little more than 7,000 K down to a little less than 4,000 K</em> (6,700 °C to 3,700 °C); the Sun, a G2 star at 5,777 K, is well within these bounds. "Middle-class" stars (late A, late F, G , mid K )of this sort have a number of characteristics considered important to planetary habitability:
• They live at least a few billion years, allowing life a chance to evolve. <em>More luminous main-sequence stars of the "O", "B", and "A" classes usually live less than a billion years and in exceptional cases less than 10 million.</em>
• They emit enough high-frequency ultraviolet radiation to trigger important atmospheric dynamics such as ozone formation, but not so much that ionisation destroys incipient life.
• They emit sufficient radiation at wavelengths conducive to photosynthesis.
• Liquid water may exist on the surface of planets orbiting them at a distance that does not induce tidal locking.
<u><em>Thus , the stars of spectral type A and F are considered reasonably to have habitable planets but much less likely to have planets with complex plant - or animak - like life.</em></u>