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3 years ago

A single fixed pulley changes the effort force in direction. true or false

2 answers:

4 0

True, the single fixed pulley changes the direction of the effort force by distributing across the rope that moves along the circumference

yan [13]3 years ago

3 0

true, because I said so.

You might be interested in

A mass is suspended on a vertical spring. Initially, the mass is in equilibrium. Then, it is pulled downward and released. The m

anastassius [24]

Answer:

d. from the equilibrium position to the bottom and then back to the equilibrium.

g. from the top position to the bottom and then back to the top.

h. from the bottom position to the top and then back to the bottom.

Explanation:

It is the case of SHM or Simple Harmonic Motion. Firstly, there is a need to understand the time interval or time period. The standard definition of time period in simple harmonic motion is

"the time period required for the system to complete its one cycle"

Now one have to consider that the system given above, the motion of mass attached to spring will follow the path of motion from equilibrium point to bottom to equilibrium point to top, then equilibrium point to the bottom and so on.

to choose right answer you must have to consider the option, in which the starting point and ending point of the mass is same. If mass starts from top, the time it will take to reach on top again, will be defined as its time period and so in the case of bottom or equilibrium as starting point. Hence, "d", "g" and "h" are right answers.

8 0

3 years ago

Sirius and its companion orbit around a common center of mass with a period of 50 years. The mass of Sirius is 2.35 times the ma

s2008m [1.1K]

Answer:

1 solar masses

Explanation:

-Sirius has to maintain equilibrium with it's companion.

-Let x be the mass of Sirius and y be the mass of it's companion.

-From the question, we know that Sirius is 2.35 times heavier than it's companion:

$\frac{x}{y}=2.35\\\\\frac{x}{y}=\frac{2.35}{1}$

Hence, the mass of it's companion is 1 solar masses

3 0

3 years ago

A 1.65 kg mass stretches a vertical spring 0.260 m If the spring is stretched an additional 0.130 m and released, how long does

Irina-Kira [14]

Answer:

The system will take approximately 0.255 seconds to reach the (new) equilibrium position.

Explanation:

We notice that block-spring system depicts a Simple Harmonic Motion, whose equation of motion is:

$y(t) = A\cdot \cos \left(\sqrt{\frac{k}{m} }\cdot t +\phi\right)$ (1)

Where:

$y(t)$ - Position of the mass as a function of time, measured in meters.

$A$ - Amplitude, measured in meters.

$k$ - Spring constant, measured in newtons per meter.

$m$ - Mass of the block, measured in kilograms.

$t$ - Time, measured in seconds.

$\phi$ - Phase, measured in radians.

The spring is now calculated by Hooke's Law, that is:

$k = \frac{m\cdot g}{\Delta y}$ (2)

Where:

$g$ - Gravitational acceleration, measured in meters per square second.

$\Delta y$ - Deformation of the spring due to gravity, measured in meters.

If we know that $m=1.65\,kg$ , $g = 9.807\,\frac{m}{s^{2}}$ and $\Delta y = 0.260\,m$ , then the spring constant is:

$k = \frac{(1.65\,kg)\cdot \left(9.807\,\frac{m}{s^{2}} \right)}{0.260\,m}$

$k = 62.237\,\frac{N}{m}$

If we know that $A = 0.130\,m$ , $k = 62.237\,\frac{N}{m}$ , $m=1.65\,kg$ , $x(t) = 0\,m$ and $\phi = 0\,rad$ , then (1) is reduced into this form:

$0.130\cdot \cos (6.142\cdot t)=0$ (1)

And now we solve for $t$ . Given that cosine is a periodic function, we are only interested in the least value of $t$ such that mass reaches equilibrium position. Then:

$\cos (6.142\cdot t) = 0$

$6.142\cdot t = \cos^{-1} 0$

$t = \frac{1}{6.142}\cdot \left(\frac{\pi}{2} \right)\,s$

$t \approx 0.255\,s$

The system will take approximately 0.255 seconds to reach the (new) equilibrium position.

4 0

3 years ago

Carlos has some soil that has too much sand mixed in for growing plants. What should he add to improve the soil for growing plan

Sauron [17]

Answer:

He would have to add <u>Top Soil </u>

Explanation:

My Mom grows a punch of plants so I asked her and she said Top Soil but if this is not the answer I am sorry :)

6 0

3 years ago

On a cold winters da,y,If you left a drink setting outside,it could freeze.Explain why in a complete sentence

sertanlavr [38]

Hello!

On a cold winters day, if you left a drink setting outside, it could freeze because the heat (related to the kinetic energy) of the atoms in the drink will be transferred to the environment to achieve energy equilibrium.

Heat transfer occurs by various mechanisms, flowing from the hottest body to the coldest, that's why the heat goes from the drink, which has a higher temperature (and kinetic energy) to the environment, which has a lower temperature. This is described by the second law of thermodynamics

6 0

4 years ago