Consider a book that weighs 15 N at rest on a flat table. How many newtons of support does the table provide?

What is the relative size and composition of the universe, a galaxy, and a solar system? Is the universe endless?

vichka [17]

Yas, the universe is endless/infinte

7 0

3 years ago

what is the major cause of the earth’s magnetic field? the earth’s liquid outer core the earth’s liquid outer core the earth’s m

GaryK [48]

The earth's liquid outer core is the major cause of the earth’s magnetic field.

<h3>What is magnetic field?</h3>

The magnetic influence on moving electric charges, electric currents, and magnetic materials is described by a magnetic field, a vector field. A force acting on a charge while it travels through a magnetic field is perpendicular to both the charge's motion and the magnetic field. The magnetic field of a permanent magnet attracts or repels other magnets as well as ferromagnetic elements like iron. A magnetic field that varies with location will also exert a force on a variety of non-magnetic materials by changing the velocity of those particles' outer electrons. Electric currents, like those utilised in electromagnets, and electric fields that change over time produce magnetic fields that surround magnetised things.

To learn more about magnetic field,visit:

brainly.com/question/11514007

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4 0

2 years ago

A steel ball rolls with a constant velocity on a tabletop 0.950 m high it rolls off and hit the ground 0.352 m from the edge of

sp2606 [1]

Answer:

0.799 m/s if air resistance is negligible.

Explanation:

For how long is the ball in the air?

Acceleration is constant. The change in the ball's height $\Delta h$ depends on the square of the time:

$\displaystyle \Delta h = \frac{1}{2} \;g\cdot t^{2} + v_0\cdot t$ ,

where

$\Delta h$ is the change in the ball's height.
$g$ is the acceleration due to gravity.
$t$ is the time for which the ball is in the air.
$v_0$ is the initial vertical velocity of the ball.

The height of the ball decreases, so this value should be the opposite of the height of the table relative to the ground. $\Delta h = -0.950\;\text{m}$ .
Gravity pulls objects toward the earth, so $g$ is also negative. $g \approx -9.81\;\text{m}\cdot\text{s}^{-2}$ near the surface of the earth.
Assume that the table is flat. The vertical velocity of the ball will be zero until it falls off the edge. As a result, $v_0 = 0$ .

Solve for $t$ .

$\displaystyle \Delta h = \frac{1}{2} \;g\cdot t^{2} + v_0\cdot t$ ;

$\displaystyle -0.950 = \frac{1}{2} \times (-9.81) \cdot t^{2}$ ;

$\displaystyle t^{2} =\frac{-0.950}{1/2 \times (-9.81)}$ ;

$t \approx 0.440315\;\text{s}$ .

What's the initial horizontal velocity of the ball?

Horizontal displacement of the ball: $\Delta x = 0.352\;\text{m}$ ;
Time taken: $\Delta t = 0.440315\;\text{s}$

Assume that air resistance is negligible. Only gravity is acting on the ball when it falls from the tabletop. The horizontal velocity of the ball will not change while the ball is in the air. In other words, the ball will move away from the table at the same speed at which it rolls towards the edge.

$\begin{aligned}\text{Rolling Velocity}&=\text{Horizontal Velocity} \\&= \text{Average Horizontal Velocity}\\ &=\frac{\Delta x}{\Delta t}=\frac{0.352\;\text{m}}{0.440315\;\text{s}}=0.0799\;\text{m}\cdot\text{s}^{-1}\end{aligned}$ .

Both values from the question come with 3 significant figures. Keep more significant figures than that during the calculation and round the final result to the same number of significant figures.

3 0

3 years ago

Sometimes students are taught that "air expands as it is heated". And sometimes they are taught that "as air expands it cools".

hram777 [196]

Answer:

Both are true under specific circumstances. And are related to Boyle's law. volume and pressure in a gas are inversely proportional.

Explanation:

There is a tendency to entropy in our reality, that is, in particular true and visible with gases, they tend to occupy the whole space where they are confined, when we heat a volume of gas, then the movement of the particles and in consequence the pressure of the gas increases and to compensate this the volume tends to be increased too, according to Boyle's law. And the opposite happens when the volume is increased, then the pressure is relieved and since the particles are further one from each other, then the temperature is lower, and therefore it cools down.

7 0

3 years ago

Find the acceleration of a hamster when it increases its velocity from rest to 8.0 m/s in 3.0 s .

Eva8 [605]

<span>Acceleration is the change in velocity divided by time.
We can find acceleration a, by the following formula

a=v-u/t

where,
v is the final velocity (in this question v=8.0 m/s)
u is the initial velocity (since the hamster starts from rest, u=0)
t is the time taken (i,e 3.0 second)
now by applying the formula we have,

a = 8.0 - 0 / 3
= 8 / 3
= 2.65 m/s</span>²<span>

The acceleration is 2.65 meters per second squared</span>

6 0

3 years ago