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You flip a coin straight up if the coin reaches a high point of 0.25 m above where you released it what was the initial speed?

Julli [10]

Answer: 2.21 m/s

Explanation:

Given

Coin reaches a height of 0.25 m above the launch point

Suppose u is the initial speed of the coin

Using the equation of motion

$\Rightarrow v^2-u^2=2as\\$

Putting values

$\Rightarrow 0^2-u^2=2\times g\times s=2\times (-9.8)\times 0.25\\\Rightarrow u^2=4.9\\\Rightarrow u=2.21\ m/s$

Thus, the initial velocity is 2.21 m/s

6 0

3 years ago

which of these statements best explains why the difference between summer and winter temperatures is greatet in Russia thanin FL

MaRussiya [10]

I don't know your statement, but one explanation for this is that Russia is mostly located on land, away from water and Florida is surrounded by water.

Water takes up the heat from the environment, so it has the effect of making the temperatures of objects around it milder: cooling down when hot, warming up when too cold.

5 0

3 years ago

A sample contains 16 g of a radioactive isotope. how much radioactive

mafiozo [28]

After one half-life, 8 g of radioactive isotope will remain in the sample.

<h3>What is radioactivity?</h3>

The act of producing radiation spontaneously is known as radioactivity. This is accomplished by an unstable atomic nucleus that want to give up some energy in order to move to a more stable form.

The following formula is used to compute the number of half lives elapsed:

$\rm N=\frac{N_0}{2^n} \\\\ N=\frac{16}{2} \\\\ N= 8 \ gram$

Hence,8 gram of radioactive isotope remains in the sample after 1 half-life.

To learn more about the radioactivity, refer to the link;

brainly.com/question/1770619

#SPJ1

7 0

2 years ago

Read 2 more answers

Two blocks are connected by a light string that passes over two frictionless pulleys. The block of mass m2 is attached to a spri

irina1246 [14]

(BELOW YOU CAN FIND ATTACHED THE IMAGE OF THE SITUATION)

Answer:

$d=\frac{2g(m1-m2)}{k}$

Explanation:

For this we're going to use conservation of mechanical energy because there are nor dissipative forces as friction. So, the change on mechanical energy (E) should be zero, that means:

$E_{i}=E_{f}$

$K_{i}+U_{i}=K_{f}+U_{f}$ (1)

With $K_{i}$ the initial kinetic energy, $U_{i}$ the initial potential energy, $K_{f}$ the final kinetic energy and $U_{f}$ the final potential energy. Note that initialy the masses are at rest so $K_{i} = 0$ , when they are released the block 2 moves downward because m2>m1 and finally when the mass 2 reaches its maximum displacement the blocks will be instantly at rest so $K_{f} =0$ . So, equation (1) becomes:

$U_{i}=U_{f}$ (2)

At initial moment all the potential energy is gravitational because the spring is not stretched so $U_{i}=U_{gi}$ and at final moment we have potential gravitational energy and potential elastic energy so $U_{f}=U_{gf}+U_{ef}$ , using this on (2)

$U_{gi}=U_{gf}+U_{ef}$ (3)

Additional if we define the cero of potential gravitational energy as sketched on the figure below (See image attached), $U_{gi}=0$ and we have by (3) :

$0= U_{gf}+U_{ef}$ (4)

Now when the block 1 moves a distance d upward the block 2 moves downward a distance d too (to maintain a constant length of the rope) and the spring stretches a distance d, so (4) is:

$0=-m1gd+m2gd+\frac{kd^{2}}{2}$