Answer:
Gravity is the attraction between two objects that have mass. The amount of gravity is directly proportional to the amount of mass of the objects and inversely proportional to the square of the distance between the objects. Gravity is a force that increases the velocity of falling objects - they accelerate.
Explanation:
<span>The crystals that form in slowly cooling magma are generally large. </span>
Question:
A skateboarder jumps horizontally off the top of a staircase at a speed of 14.5 and lands at bottom of the stairs. The staircase has a horizontal length of 8.00 m. We can ignore air resistance. What is the skater's vertical displacement during the jump?
Answer:
y = 1.48 m
Explanation:
Projectile motion is a two dimensional motion experienced by an object or particle that is subjected near the Earth's surface and moves along a curved path under the influence of gravity only. The path followed by projectile motion is called projectile path.
As the skateboarder followed the projectile path, and we know that in projectile motion the horizontal component of the velocity remain constant throughout his motion. So there is no acceleration along horizontal path.
Also Skateboard jumps horizontally, So initial velocity has only horizontal component.
Horizontal component of initial velocity = 
= 14.5 m/s
Horizontal displacement = x = 8.00 m
Vertical displacement = y = ?
Using the following formula
x = t
8 = (14.5)(t)
t = 0.55 s
As skateboarder jumps horizontally, So there is no vertical component of velocity.
According to 2nd equation of motion
y = 
As 
So
y = 0.5gt²
y = 0.5*9.8*(0.55)²
y = 1.48 m
Answer:
The leaves of the electroscope move further apart.
Explanation:
This is what happens; when the positive object is brought near the top, negative charges migrating from the gold leaves to the top. This is because the negative charges in the gold are attracted by the positive charge. Thus, it leaves behind a net positive charge on the leaves, though the scope remains neutral overall. To that effect, the leaves repel each other and move apart. If a finger touches the top of the electroscope at the moment when the positive object remains near the top, it basically grounds the electroscope and thus the net positive charge in the leaves flows to the ground through the finger. However, the positive object continues to "hold" negative charges in place at the top. Ar this moment the gold leaves have lost their net positive charge, so they no longer repel, and they move closer together. If the positive object is moved away, the negative charges at the top are no longer attracted to the top, and they redistribute themselves throughout the electroscope, moving into the leaves and charging them negatively.
Thus, the leaves move apart from each other again and we now have a negatively charged electroscope. If a negatively charged object is now brought close to the top, but without touching, the negative charges already in the electroscope will be repelled down toward the leaves, thereby making them more negative, causing them to repel more, and hence move even further apart.
So, the leaves move further apart.
Answer:
20 N to the left
Explanation:
For the first question, add the two forces as they are acting in the same direction.
So, 8 + 12 = 20 N to the left
