Answer:
J electrons
Explanation:
Electrons are the negatively charged subatomic particles that surrounds the nucleus of an atom.
- Electrons occupy the bulk volume of an atom.
- These particle was discovered by J.J Thomson
- They found orbiting the extra-nuclear space of every atom.
- The nucleus is made up of protons and neutrons.
Answer:
The density of beryllium is 1.85 g/cm³. Thus given metal is beryllium.
Explanation:
Given data:
Mass of metal = 37 g
Volume of metal = 20cm³
Which metal is this = ?
Solution:
We will solve this problem by using density formula. After finding density we will check from literature which metal has a density similar to our calculated density.
d = m/v
d = 37 g/ 20cm³
d = 1.85 g/cm³
The density of beryllium is 1.85 g/cm³. Thus given metal is beryllium.
T<span>his is a straightforward question related to the surface energy of the droplet. </span>
<span>You know the surface area of a sphere is 4π r² and its volume is (4/3) π r³. </span>
<span>With a diameter of 1.4 mm you have an original droplet with a radius of 0.7 mm so the surface area is roughly 6.16 mm² (0.00000616 m²) and the volume is roughly 1.438 mm³. </span>
<span>The total surface energy of the original droplet is 0.00000616 * 72 ~ 0.00044 mJ </span>
<span>The five smaller droplets need to have the same volume as the original. Therefore </span>
<span>5 V = 1.438 mm³ so the volume of one of the smaller spheres is 1.438/5 = 0.287 mm³. </span>
<span>Since this smaller volume still has the volume (4/3) π r³ then r = cube_root(0.287/(4/3) π) = cube_root(4.39) = 0.4 mm. </span>
<span>Each of the smaller droplets has a surface area of 4π r² = 2 mm² or 0.0000002 m². </span>
<span>The surface energy of the 5 smaller droplets is then 5 * 0.000002 * 72.0 = 0.00072 mJ </span>
<span>From this radius the surface energy of all smaller droplets is 0.00072 and the difference in energy is 0.00072- 0.00044 mJ = 0.00028 mJ. </span>
<span>Therefore you need roughly 0.00028 mJ or 0.28 µJ of energy to change a spherical droplet of water of diameter 1.4 mm into 5 identical smaller droplets. </span>
Answer: D and A
Explanation: <u>D</u> cuz you need water to have good soil and <u>A</u> cuz you get better soil if its warm. (: ( 'u' ) ( 'U' )
Answer:
You can make the ramp really steep and hold the marble at the top of it
Explanation:
