Which type of energy is stored in chemical compounds and released in chemical reactions?

Which row shows what happens to the temperature of a solid as it melts and what happens to the temperature when

frez [133]

When ice melts, its temperature doesn't change ... ice at 32 degrees becomes water at 32 degrees.

When water boils, its temperature doesn't change ... water at 212 degrees becomes steam at 212 degrees.

The row that says both of these is row-D .

4 0

3 years ago

The radius k of the equivalent hoop is called the radius of gyration of the given body. Using this formula, find the radius of g

Morgarella [4.7K]

Here is the full question:

The rotational inertia I of any given body of mass M about any given axis is equal to the rotational inertia of an equivalent hoop about that axis, if the hoop has the same mass M and a radius k given by:

$k=\sqrt{\frac{I}{M} }$

The radius k of the equivalent hoop is called the radius of gyration of the given body. Using this formula, find the radius of gyration of (a) a cylinder of radius 1.20 m, (b) a thin spherical shell of radius 1.20 m, and (c) a solid sphere of radius 1.20 m, all rotating about their central axes.

Answer:

a) 0.85 m

b) 0.98 m

c) 0.76 m

Explanation:

Given that: the radius of gyration $k=\sqrt{\frac{I}{M} }$

So, moment of rotational inertia (I) of a cylinder about it axis = $\frac{MR^2}{2}$

$k=\sqrt{\frac{\frac{MR^2}{2}}{M} }$

$k=\sqrt{{\frac{MR^2}{2}}* \frac{1}{M} }$

$k=\sqrt{{\frac{R^2}{2}}$

$k={\frac{R}{\sqrt{2}}$

$k={\frac{1.20m}{\sqrt{2}}$

k = 0.8455 m

k ≅ 0.85 m

For the spherical shell of radius

(I) = $\frac{2}{3}MR^2$

$k = \sqrt{\frac{\frac{2}{3}MR^2}{M} }$

$k = \sqrt{\frac{2}{3} R^2}$

$k = \sqrt{\frac{2}{3} }*R$

$k = \sqrt{\frac{2}{3}} *1.20$

k = 0.9797 m

k ≅ 0.98 m

For the solid sphere of radius

(I) = $\frac{2}{5}MR^2$

$k = \sqrt{\frac{\frac{2}{5}MR^2}{M} }$

$k = \sqrt{\frac{2}{5} R^2}$

$k = \sqrt{\frac{2}{5} }*R$

$k = \sqrt{\frac{2}{5}} *1.20$

k = 0.7560

k ≅ 0.76 m

6 0

3 years ago

If a spring is stretched 4m from its starting length when 20n of force is applied, then how much work (in joules) is done by the

lys-0071 [83]

ANSWER:

250 J

STEP-BY-STEP EXPLANATION:

F = 20N is required to stretch the spring by 4 meters

We know that the force is equal to:

$F=k\cdot x$

We solve for k (spring constant):

$k=\frac{F}{x}=\frac{20}{4}=5\text{ N/m}$

The work done in stretching the spring is given by the following equation (in this case the stretch is 10 meters:

$\begin{gathered} W=\frac{1}{2}k\cdot x^2 \\ \text{ Replacing} \\ W=\frac{1}{2}\cdot5\cdot10^2 \\ W=250\text{ J} \end{gathered}$

The work required is 250 joules.

5 0

1 year ago

Explain four contributory factors of unequal access to basic resources

serious [3.7K]

Answer:

Answer. The big five factors of poverty (as a social problem) include: ignorance, disease, apathy, dishonesty and dependency. These, in turn, contribute to secondary factors such as lack of markets, poor infrastructure, poorleadership, bad governance, under-employment, lack of skills, lack of capital, and others.

3 0

2 years ago

A child on a bike stops pedaling and coasts. Because he is not pedaling he slows down at a rate of 1 m/s^2. In the 5 seconds aft

mrs_skeptik [129]

Explanation:

Let u is the initial speed of the bike. Finally, the bike stops, v = 0

Deceleration of the bike, $a=-1\ m/s^2$