Use the scenario below for questions 4-7.

Consider the following four objects: a hoop, a flat disk, a solid sphere, and a hollow sphere. Each of the objects has mass M an

Mumz [18]

Answer:

The hoop

Explanation:

We need to define the moment of inertia of the different objects, that is,

DISK:

$I_{disk} = \frac{1}{2} mR^2$

HOOP:

$I_{hoop} = mR^2$

SOLID SPHERE:

$I_{ss} = \frac{2}{5}mR^2$

HOLLOW SPHERE

$I_{hs} = \frac{2}{3}mR^2$

If we have the same acceleration for a Torque applied, then

$mR^2>\frac{2}{3}mR^2>\frac{1}{2} mR^2>\frac{2}{5}mR^2$

$I_{hoop}>I_{hs} >I_{disk}>I_{ss}$

The greatest momement of inertia is for the hoop, therefore will require the largest torque to give the same acceleration

4 0

3 years ago

Calculate the electric force an electron exerts upon a proton inside a He atom if they are d=2.7⋅10^-10m apart.

maksim [4K]

Explanation:

Charge of electron in He, $q_e=1.6\times 10^{-19}\ kg$

Charge of proton in He, $q_p=1.6\times 10^{-19}\ kg$

Distance between them, $d=2.7\times 10^{-10}\ m$

We need to find the electric force between them. It is given by :

$F=k\dfrac{q_eq_p}{d^2}$

$F=-9\times 10^9\times \dfrac{(1.6\times 10^{-19}\ C)^2}{(2.7\times 10^{-10}\ m)^2}$

$F=-3.16\times 10^{-9}\ N$

Since, there are two protons so, the force become double i.e.

$F=2\times 3.16\times 10^{-9}\ N$

$F=6.32\times 10^{-9}\ N$

So, the correct option is (c). Hence, this is the required solution.

6 0

3 years ago

Why does a pencil in a glass container filled with water appear to be bent?

Bogdan [553]

The phenomenon is called "refraction". It's the process of
light waves bending toward a different direction when they
cross a boundary between different media ... in this case,
from water into air.

Your brain doesn't know that the light waves bent toward a
new direction when they came out of the water into the air,
so your brain locates the bottom half of the pencil just like it
ALWAYS does ... in the direction the light waves are coming FROM.

4 0

4 years ago

Read 2 more answers

In no more than five simple statements, use the kinetic theory to explain why an iron bar expands when it is heated.

lozanna [386]

Answer:

Iron expands because heating increases the space between the molecules

Explanation:

According to the kinetic molecular theory, all matter is composed of atoms and molecules which are in constant motion.

When a substance is heated, molecules of the substance begin to vibrate faster. This faster vibration leads to increased space between the molecules (expansion) . The kind of motion motion and degree of spacing of the molecules determine the state of matter in which the substance is found.

Hence, when an iron bar is heated, it expands due to increased motion of its molecules leading to spaces between them.

7 0

4 years ago

Which of the following is true for balancing equations? A. There must be an equal number of atoms of each element on both sides

Zielflug [23.3K]

<h3><u>Answer</u>;</h3>

A. There must be an equal number of atoms of each element on both sides of the equation.

<h3><u>Explanation;</u></h3>

Chemical equations need to be balanced in order to satisfy the law of conservation of matter, which states that in a closed system matter is neither created nor destroyed.
The number of atoms of each element should be equal on either side of the equation, that is the reactants and product side.

3 0

3 years ago