What is true about coal as an energy source

The atomic mass of an atom can be found by

Anton [14]

A. Adding the number of protons and number of neutrons in the atom

Electrons are so incredibly small that the number of electrons makes almost no difference in the atomic mass. So b and c are not the answer.

D doesn't really make sense because like if you want to know the mass of a basket of apples and oranges, you'd add up the apples' and oranges' masses, not subtract.

5 0

2 years ago

A playground slide is 8.80 ft long and makes an angle of 25.0° with the horizontal. A 63.0-kg child, initially at the top, slide

mario62 [17]

Answer:

initial: 1654.6 J, final: 0 J, change: -1654.6 J

Explanation:

The length of the slide is

L = 8.80 ft = 2.68 m

So the height of the child when he is at the top of the slide is (with respect to the ground)

$h = L sin \theta = (2.68 m)sin 25.0^{\circ}=1.13 m$

The potential energy of the child at the top is given by:

$U = mgh$

where

m = 63.0 kg is the mass of the child

g = 9.8 m/s^2 is the acceleration due to gravity

h = 1.13 m

Substituting,

$U=(63.0 kg)(9.8 m/s^2)(2.68 m)=1654.6 J$

At the bottom instead, the height is zero:

h = 0

So the potential energy is also zero: U = 0 J.

This means that the change in potential energy as the child slides down is

$\Delta U = 0 J - (1654.6 J) = -1654.6 J$

7 0

2 years ago

1) How is density different than mass?

elixir [45]

Mass is a measure of how much matter there is within an object, typically given in grams. Mass is not affected by gravity, so a given object would have the same mass on earth as in outer space. Density is the amount of mass in an object per a certain amount of volume

3 0

2 years ago

A toroidal solenoid has an inner radius of 12.0 cm and an outer radius of 15.0 cm . It carries a current of 1.50 A . Part A How

tensa zangetsu [6.8K]

Answer:

The number of turns is $N = 1750 \ turns$

Explanation:

From the question we are told that

The inner radius is $r_i = 12.0 \ cm = 0.12 \ m$

The outer radius is $r_o = 15.0 \ cm = 0.15 \ m$

The current it carries is $I = 1.50 \ A$

The magnetic field is $B = 3.75 mT = 3.75 *10^{-3} \ T$

The distance from the center is $d = 14.0 \ cm = 0.14 \ m$

Generally the number of turns is mathematically represented as

$N = \frac{2 * \pi * d * B}{ \mu_o * r_o }$

Generally $\mu_o$ is the permeability of free space with value

$\mu_o = 4\pi * 10^{-7} \ N/A^2$

So

$N = \frac{2 * 3.142 * 0.14 * 3.75 *10^{-3} }{ 4\pi * 10^{-7} * 0.15 }$

$N = 1750 \ turns$

5 0

3 years ago

How can you tell there is only one atom of oxygen in H2O?

kow [346]

Answer:

For H2O, there is one atom of oxygen and two atoms of hydrogen. A molecule can be made of only one type of atom. In its stable molecular form, oxygen exists as two atoms and is written O2. to distinguish it from an atom of oxygen O, or ozone, a molecule of three oxygen atoms, O3.

Explanation:

4 0

3 years ago