A _____ is a quantity that has magnitude and direction

inna [77]

A : lighter than lead shot, reducing its velocity and distance

4 0

4 years ago

It takes 8 seconds for a pulley system to lift a load that weights 400N to a height of 10 m. How much power is required?.

mariarad [96]

Answer:

C. 500 watts

Explanation:

power is defined as the rate of work done

$power=\frac{work.done}{time}$

When a force causes a object to move, work is being done on the object by the force.

$work.done=force*displacement\\=400*10\\=4000J$

$power=\frac{4000J}{8s}\\=500 W$

3 0

4 years ago

List 5 types of action energy and 4 types of potential energy

Taya2010 [7]

Well, kinetic energy is defined as energy in motion (or as you said, action energy). Now, in order to characterize something as kinetic energy, it needs to be in motion (e.x., movement on a rollercoaster, a ball falling, a ball rolling, a person running, or a car in motion, really, anything moving).
Potential energy is stored energy. For example, it could be the farthest point back when you pull a slingshot. Or being at the very top of a hill right before you fall back down it, or holding a ball at its highest point before you drop it. Another example, is water stored behind a dam waiting to be released. Hope this helps!

5 0

3 years ago

Why do disk stars bob up and down as they orbit the galaxy?

Pie

Answer:

When the stars get a little bit farther from the disk, the other stars that are still in the disk will pull them toward it as a consequence of the gravity between them.

Explanation:

Galaxies have different structures due to parameters as the orbit of the stars around the center of the galaxy or the metallicity¹ of the stars (which serves to find the age of the stars). For example, in the case of the Milky Way, it has:

The Halo

The Bulge

The Thick Disk

The Thin Disk

The Halo has old stars with low metallicities and random orbits, while the bulge has stars with the same random motions like the one in the Halo.

The Thick Disk has stars with orbits oriented in the same direction but with metallicities a little bit higher than the one from the Halo but lower than the stars in the Thin Disk.

The stars that are in the thin disk have orbits oriented in the same direction and are the ones with the higher metallicity levels, which means that they are the most younger in the galaxy.

In general the stars in the disk of the galaxy (thick disk and thin disk) goes up and down as they orbit the center of the galaxy, <u>the reason for this is that when they get a little bit farther from the disk, the stars that are still in the disk pull them back toward it as a consequence of the gravity between them. </u>

Remember the equation of the Universal gravitation law:

$F = G\frac{m1.m2}{R^{2}}$ (1)

Where F is the force of gravity, G is the gravitational constant, m1 and m2 are the masses of two objects and R is the distance between them.

Notice how equation 1 expresses that the force of gravity is inversely proportional to the square of the distance between the two objects, which means that the force of gravity will decrease as the square of the distance increase.

Key terms:

¹Metallicity: the abundance of heavier elements against the presence of Helium or Hydrogen.

7 0

3 years ago

Compare and contrast potential and kinetic energy

inysia [295]

Kinetic and Potential Energy HistoryA roller coaster train going down hill represents merely a complex case as a body is descending an inclined plane. Newton's first two laws relate force and acceleration, which are key concepts in roller coaster physics. At amusement parks, Newton's laws can be applied to every ride. These rides range from 'The Swings' to The 'Hammer'. Newton was also one of the developers of calculus which is essential to analyzing falling bodies constrained on more complex paths than inclined planes. A roller coaster rider is in an gravitational field except with the Principle of Equivalence.Potential EnergyPotential energy is the same as stored energy. The "stored" energy is held within the gravitational field. When you lift a heavy object you exert energy which later will become kinetic energy when the object is dropped. A lift motor from a roller coaster exerts potential energy when lifting the train to the top of the hill. The higher the train is lifted by the motor the more potential energy is produced; thus, forming a greater amount if kinetic energy when the train is dropped. At the top of the hills the train has a huge amount of potential energy, but it <span>has very little kinetic energy.Kinetic Energy The word "kinetic" is derived from the Greek word meaning to move, and the word "energy" is the ability to move. Thus, "kinetic energy" is the energy of motion --it's ability to do work. The faster the body moves the more kinetic energy is produced. The greater the mass and speed of an object the more kinetic energy there will be. Hope this helped:))))</span>

7 0

3 years ago

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