What is the name of a very porous igneous rock that is so light that it floats?

Se dispone de dos vasos con agua a 20 grados y queremos calentarlo hasta alcanzar 50 grados. Si el primero contiene 0,5l y el se

BigorU [14]

Answer:

The cup with 0.5L

Explanation:

To know what amount of water you take into account the specific heat of the water. The specific heat of water is:

$c_{water}=4186\frac{J}{kg\°C}$

Thus, 4186 J of energy are needed to icrease the temperature of 1 kg water in 1°C. Then, more grams of water will need more energy.

You have that one cup has 0.5 L and the other one has 750mL = 0.75L

The second cup of water will need more heat because the amount of water contained in the second cup is greater than in the first cup with 0.5L

4 0

2 years ago

Janice has just measured the density of an object. Which value is possible? (Density: D = )

Sunny_sXe [5.5K]

By definition, the density of an object is given by:

$D = \frac{M}{V}$

Where,

M: mass of the object

V: volume of the object

Since the mass and volume of an object are numerical values greater than zero, then it follows that:

$D> 0$

It is important to respect the units of each measure.

For this case we can use the grams for the mass and cubic centimeters for the volume.

Answer:

A possible value for density is given by:

$6 \frac{g}{cm^3}$

7 0

2 years ago

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On a graph of position vs. time, a negative slope means what about motion of the object?

Aleksandr-060686 [28]

Answer:

Explanation:

A positive v time graph is a velocity graph. If the position/time is negative, then the slope of the line is negative. If the line is indicative of the velocity, which it is, that means that the velocity is negative (decreasing). The first choice is the one you want.

6 0

2 years ago

5 Which of the following must be transformed into electrical energy when biomass is used as an energy resource? * DS (20 Points)

Lemur [1.5K]

Answer:

nuclear energy

Explanation:

3 0

2 years ago

A metal block of mass 3 kg is falling downward and has velocity of 0.44 m/s when it is 0.8 m above the floor. It strikes the top

Anton [14]

Answer:

$y_{max} = 0.829\,m$

Explanation:

Let assume that one end of the spring is attached to the ground. The speed of the metal block when hits the relaxed vertical spring is:

$v = \sqrt{(0.8\,\frac{m}{s})^{2} + 2\cdot (9.807\,\frac{m}{s^{2}} )\cdot (0.4\,m)}$

$v = 2.913\,\frac{m}{s}$

The maximum compression of the spring is calculated by using the Principle of Energy Conservation:

$(3\,kg)\cdot (9.807\,\frac{m}{s^{2}})\cdot (0.4\,m) + \frac{1}{2}\cdot (3\,kg)\cdot (2.913\,\frac{m}{s} )^{2} = (3\,kg) \cdot (9.807\,\frac{m}{s^{2}})\cdot (0.4\,m-\Delta s) + \frac{1}{2}\cdot (2000\,\frac{N}{m})\cdot (\Delta s) ^{2}$

After some algebraic handling, a second-order polynomial is formed:

$12.728\,J = \frac{1}{2}\cdot (2000\,\frac{N}{m} )\cdot (\Delta s)^{2} - (3\,kg)\cdot (9.807\,\frac{m}{s^{2}} )\cdot \Delta s$

$1000\cdot (\Delta s)^{2}-29.421\cdot \Delta s - 12.728 = 0$

The roots of the polynomial are, respectively:

$\Delta s_{1} \approx 0.128\,m$

$\Delta s_{2} \approx -0.099\,m$

The first root is the only solution that is physically reasonable. Then, the elongation of the spring is:

$\Delta s \approx 0.128\,m$

The maximum height that the block reaches after rebound is:

$(3\,kg) \cdot (9.807\,\frac{m}{s^{2}} )\cdot (0.4\,m-\Delta s) + \frac{1}{2}\cdot (2000\,\frac{N}{m})\cdot (\Delta s)^{2} = (3\,kg)\cdot (9.807\,\frac{m}{s^{2}} )\cdot y_{max}$

$y_{max} = 0.829\,m$

4 0

2 years ago

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