What happens when the temperature of an object decreases

Helppp plssss I am needing help for science and there is a photo pls answer

disa [49]

Answer:

sorry I don't really know :P

Explanation:

7 0

3 years ago

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During a blackout, you are trapped in a tall building. you want to call rescuers on your cell phone, but you can't remember whic

Gennadij [26K]

Let the height where we are trapped is H

now to find the time to reach the key at the bottom is given as

$y = v_i t + \frac{1}{2}at^2$

now we have

$H = \frac{1}{2}gt^2$

$t = \sqrt{\frac{2H}{g}}$

now if the speed of sound is considered to be 340 m/s then time taken by the sound to reach at the top is given as

$t = \frac{H}{340}$

now the total time is given as

$\sqrt{\frac{2H}{g}} + \frac{H}{340} = 3.27$

now by solving above equation we have

H = 48 m

now height of one floor is 3 m

so our position must be

$N = \frac{48}{3} = 16 th \:floor$

3 0

3 years ago

A block–spring system vibrating on a frictionless, horizontal surface with an amplitude of 7.0 cm has an energy of 14 J. If the

Bingel [31]

Answer:

$E_T= 28J$

Explanation:

The energy of Mass-Spring System the sum of the potential energy of the block plus the kinetic energy of the block:

$E_T=U+K=\frac{1}{2} k \Delta x^2+\frac{1}{2} mv^2$

Where:

$\Delta x=Amplitude\hspace{3}or\hspace{3}d eformation\hspace{3} of\hspace{3} the\hspace{3} spring\\m=Mass\hspace{3}of\hspace{3}the\hspace{3}block\\k=Constant\hspace{3}of\hspace{3}the\hspace{3}spring\\v=Velocity\hspace{3}of\hspace{3}the\hspace{3}block$

There are two cases, the first case is when the spring is compressed to its maximum value, in this case the value of the kinetic energy is zero, since there is no speed, so:

$E_T=\frac{1}{2} k \Delta x^2\\\\14=\frac{1}{2} k7^2\\\\Solving\hspace{3} for\hspace{3} k\\\\k=\frac{28}{49} =\frac{4}{7}$

The second case is when the block passes through its equilibrium position, in this case the elastic potential energy is zero since $\Delta x=0$ , so:

$E_T=\frac{1}{2} mv^2\\\\14=\frac{1}{2} mv^2\\\\Solving\hspace{3} for\hspace{3} v\\\\v^2=\frac{28}{m}$

Now, let's find the energy of the system when the block is replaced by one whose mass is twice the mass of the original block using the previous data:

$E_T=U+K=\frac{1}{2} k \Delta x^2+\frac{1}{2} m_2v^2$

Where in this case:

$m_2=New\hspace{3}mass=Twice\hspace{3} the\hspace{3} mass \hspace{3}of\hspace{3} the\hspace{3} original=2m$

Therefore:

$E_T=\frac{1}{2} (\frac{4}{7} ) (7^2)+\frac{1}{2} (2m)(\frac{28}{m_2})=\frac{1}{2} (\frac{4}{7} ) (7^2)+\frac{1}{2} (2m)(\frac{28}{2m})=14+14=28J$

8 0

3 years ago

What must you do to calculate a meaningful value of distance from the following equation?

ss7ja [257]

Answer:

Convert all the times to either hours or seconds

Explanation:

One time unit is in hours, and the other is in seconds. In order to do the math, the units need to be the same. So you either need to convert hours to seconds, or seconds to hours.

5 0

2 years ago

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What are some similarity’s and differences between potential and kinetic energy

Lady_Fox [76]

Answer: posteintal is like something that is about to happen and kinetic is like the energy while something is moving

Explanation:

6 0

3 years ago