Answer: 80 Newton
Explanation:
Initial velocity of ball = +20 m/s.
Final velocity of ball = -20 m/s
Mass of ball = 0.1kg
Time taken = 0.05 seconds
Average force = (Change in momentum of moving ball / Time taken)
Since, change in momentum = Mass (final velocity - initial velocity)
Change in momentum =0.1 x (-20 - (+20))
= 0.1 x (-20-20)
= 0.1 x (-40)
= -4.0 kgm/s
Then, put -4.0 kgm/s in the equation of force when Average Force = (Change in momentum / Time taken)
= (-4.0kgm/s / 0.05 seconds)
= 80Newton (note that the negative sign does not reflect on the magnitude of force)
Thus, the average force exerted on the ball is 80N
In comparing the Ptolemaic system to the Copernican system, neither is entirely correct since Ptolemy said the earth was at the center and Copernicus said <span>the planets had circular orbits. This is correct</span>
Answer:
v = 31.3 m / s
Explanation:
The law of the conservation of stable energy that if there are no frictional forces mechanical energy is conserved throughout the point.
Let's look for mechanical energy at two points, the highest where the body is at rest and the lowest where at the bottom of the plane
Highest point
Em₀ = U = m g y
Lowest point
= K = ½ m v²
As there is no friction, mechanical energy is conserved
Em₀ =
m g y = ½ m v²
v = √ 2 g y
Where we can use trigonometry to find and
sin 30 = y / L
y = L sin 30
Let's replace
v = RA (2 g L sin 30)
Let's calculate
v = RA (2 9.8 100.0 sin30)
v = 31.3 m / s
D.Both B and C
As they not allow heat to pass through and usually non metal
Most likely in a shallow sea environment.
