What is the work done by 20 Newton force applied at an angle of 45.0° to move a box a horizontal distance of 40 meters

At t1 = 2.00 s, the acceleration of a particle in counterclockwise circular motion is 6.00 i + 4.00 j m/s2 . It moves at constan

Jet001 [13]

The particle moves with constant speed in a circular path, so its acceleration vector always points toward the circle's center.

At time $t_1$ , the acceleration vector has direction $\theta_1$ such that

$\tan\theta_1=\dfrac{4.00}{6.00}\implies\theta_1=33.7^\circ$

which indicates the particle is situated at a point on the lower left half of the circle, while at time $t_2$ the acceleration has direction $\theta_2$ such that

$\tan\theta_2=\dfrac{-6.00}{4.00}\implies\theta_2=-56.3^\circ$

which indicates the particle lies on the upper left half of the circle.

Notice that $\theta_1-\theta_2=90^\circ$ . That is, the measure of the major arc between the particle's positions at $t_1$ and $t_2$ is 270 degrees, which means that $t_2-t_1$ is the time it takes for the particle to traverse 3/4 of the circular path, or 3/4 its period.

Recall that

$\|\vec a_{\rm rad}\|=\dfrac{4\pi^2R}{T^2}$

where $R$ is the radius of the circle and $T$ is the period. We have

$t_2-t_1=(5.00-2.00)\,\mathrm s=3.00\,\mathrm s\implies T=\dfrac{3.00\,\rm s}{\frac34}=4.00\,\mathrm s$

and the magnitude of the particle's acceleration toward the center of the circle is

$\|\vec a_{\rm rad}\|=\sqrt{\left(6.00\dfrac{\rm m}{\mathrm s^2}\right)^2+\left(4.00\dfrac{\rm m}{\mathrm s^2}\right)^2}=7.21\dfrac{\rm m}{\mathrm s^2}$

So we find that the path has a radius $R$ of

$7.21\dfrac{\rm m}{\mathrm s^2}=\dfrac{4\pi^2R}{(4.00\,\mathrm s)^2}\implies\boxed{R=2.92\,\mathrm m}$

8 0

3 years ago

: match each description below with the type of star that is described. You may assume that all of the stars described have appr

EleoNora [17]

Explanation:

A. White Dwarf: It is the end stage of a Sun-like star. At the end the red giant star will throw away the outer layers in the form a shell and in the center a hot and bright core will remain. This core consists of carbon and oxygen but the conditions are not suitable to start the fusion of carbon and oxygen.

B. Protostar: It is the initial stage of a star. Here the fuel is available but still the temperature and pressure are not enough to start the nuclear fusion.

C. Main Sequence Star: A star that is fusing Hydrogen in the core to make Helium and releasing the energy in this process. Sun is currently in its main sequence stage. A star spend 90% of its lifetime in main sequence stage.

D. Red Giant Star: In such stars, the hydrogen has been exhausted and only Helium is left. As the core starts contracting under gravity, the conditions are apt for the fusion of Helium to begin. Helium starts fusing to make carbon while in the outer layer Hydrogen to Helium process goes on. As a result the star expands.

5 0

3 years ago

8.92 A 45.0 kg woman stands up in a 60.0 kg canoe 5.00 m long. She walks from a point 1.00 m from one end to a point I .00 m fro

omeli [17]

The distance that the canoe moves in this process is 1.29 meters.

We first have to find the center of mass

$X = \frac{MsXs+McXc}{Mw+Mc} \\\\$

Where

Ms = Woman's mass = 45

Mc = Canoe's mass = 60kg

Xs = position from left= 1 cm

Xc = position from left end of canoe's mass = 2.5cm

When we put these values into the equation we have:

$X=\frac{45*1+60*2.5}{45+60} \\\\= 1.857\\$

The center of gravity lies at the center of this boat. Therefore,

$Xc = \frac{L}{2} \\\\L = 5 m long\\\\\frac{5}{2} =2.5$

5.00 - 1. 00 = 4 meters

$\frac{45*4+60*2.5}{45+60} = 3.14meters\\\\$

To get the distance that is moved by this canoe

distance = 3.143-1.857

= 1.286

≈ 1.29 meters

The distance that the canoe moves in this process is 1.29 meters.

6 0

2 years ago

PLEASE HELP!!!!

VashaNatasha [74]

In my opinion I would say all of the above; because people's job depends on where they live or how their environment is. The way they travel is also affected because we can't travel by car through water and can't use a boat in land. Free time as well because people like to travel and or just stay at home depending on the weather which is part of earths features.

7 0

3 years ago

Which of these properties of an object best quantifies its inertia: velocity, acceleration, volume, mass, or temperature?

LuckyWell [14K]

Answer:

Mass

Explanation:

Inertia is essentially an object's tendency to stay in motion or at rest unless it is forced to do otherwise (pun intended). It only makes sense to me that mass would best quantify an object's inertia, because an object with more mass would be harder to move and/or stop from moving.

3 0

3 years ago