<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:
The block will not move.
Explanation:
We'll begin by calculating the frictional force. This can be obtained as follow:
Coefficient of friction (µ) = 0.6
Mass of block (m) = 3 Kg
Acceleration due to gravity (g) = 10 m/s²
Normal reaction (R) = mg = 3 × 10 = 30 N
Frictional force (Fբ) =?
Fբ = µR
Fբ = 0.6 × 30
Fբ = 18 N
From the calculations made above, the frictional force of the block is 18 N. Since the frictional force (i.e 18 N) is bigger than the force applied (i.e 14 N), the block will not move.
Explanation:
Magnet: It has two poles: South pole and North pole.
Magnetic field lines are stronger near the poles of the magnet.
Same poles repel each other. There is a magnetic force of repulsion between the same poles. North- North poles repel each other.
Unlike poles attract each other. There is magnetic force of attraction between the opposite poles. South- North poles attract each other.
Mono poles cannot exist.
From the given statements, the magnetic poles are described by:
A north pole must exist with a south pole.
Two south poles placed near each other will repel each other.
A north pole and a south pole placed near each other will attract each other.
The gravitation force with which the earth is being pulled can be determined by applying Newton's law of universal gravitation.
<h3>
What is gravitation force?</h3>
According Newton's law of universal gravitation, the force exerted between two objects in the universe is directly proportional to the product of masses of the two objects and inversely proportional to the square of the distance between the two objects.
Mathematically, the formula for gravitation force is given as;
F = GmM/R²
where;
- m is the mass of the object
- M is mass of earth
- R is the distance of the object from earth
- G is universal gravitation constant
If the mass of the object is know and the distance between earth and the object is also known, the force with which the earth is being pulled can be calculated by applying Newton's law of universal gravitation as shown in the above equation.
Thus, the force with which the earth is being pulled can calculated as well.
Learn more about gravitation force here: brainly.com/question/27943482
#SPJ1
Answer:
Global warming
Explanation:
Global warming is caused when co2 gases cause the earth to heat up and cause the environment to change