Which of the following does not affect electrical resistance?

Fofino [41]

Answer:

An object at rest will stay at rest and an object in motion will stay in motion unless it is acted upon by an unbalanced/external force.

8 0

3 years ago

the system shown above is released from rest. if friction is negligible, the acceleration of the 4.0 kg block sliding on the tab

JulsSmile [24]

The acceleration of the first block (4 kg) is -9.8 m/s².

The given parameters:

Mass of the first block, m₁ = 4.0 kg
Mass of the second block, m₂ = 2.0 kg

The net force on the system of the two blocks is calculated as follows;

$m_2 g - T = m_1 a$

where;

T is the tension in the connecting string due weight of the first block

$m_2 g - m_1 g = m_1 a\\\\a = \frac{m_2 g - m_1g}{m_1} \\\\a = \frac{g(m_2 - m_1)}{m_1} \\\\a = \frac{9.8(2-4)}{2} \\\\a = -9.8 \ m/s^2$

Thus, the acceleration of the first block (4 kg) is -9.8 m/s².

Learn more about net force on two connected blocks here: brainly.com/question/13539944

5 0

3 years ago

Sodium chloride (NaCl) is an ionic solid. It dissolves easily in water. Which property of water allows it to dissolve NaCl? Wate

marin [14]

Answer:

Water is a polar molecule

Explanation:

The general solubility rule is that like dissolves like. In short, polar solutes would dissolve in polar solvents. Non polar solutes also dissolves on non polar solvents.

NaCl is an ionic molecule which forms as a result of transfer of electrons from one atom to another. The transfer of electrons makes the atoms oppositely a charged ions and they become polar.

Water is made up of Hydrogen H⁺ ions and hydroxy ions OH⁻. Water is an heteronuclear covalent molecule. Here, there is an unequal sharing of electrons as one atom pulls the shared electron more closer. This leaves a partial negative charge on the more electronegative atom and a partial positive charge on the other.

This polar nature of water NaCl makes dissolution easy.

5 0

3 years ago

2nd question!!!!!!!!!!!!!!!!!!!

DochEvi [55]

Answer:

D.

Explanation:

6 0

2 years ago

It would be really helpful if u help me solving this question. PLEASE!!!

sweet [91]

Answer: The students will determine the two fixed points of the thermometer:

Lower fixed point = 0 degree Celsius

Upper fixed point = 100 degree Celsius

Then divide the thermometer with equal intervals

The room temperature will be the point at which the themometric substance remains constant when rising from ice point.

Explanation:

Apparatus available:

Unmarked thermometer

250 cm3 glass beaker

crushed ice

water

heatproof mat

clamp, boss and stand

meter rule

Added apparatus

Bunsen burner

Stirrer

Method

The students will determine the two fixed points of the thermometer:

Lower fixed point = 0 degree Celsius

Upper fixed point = 100 degree Celsius

Then divide the thermometer with equal intervals

Procedures

Set up the apparatus of illustrated in the attached figure.

Immerse the unmarked thermometer into the ice in the beaker.

When the level indicated by the thermometric substance remains steady after some time, a mark will be made at that point. This mark will corresponds to the ice point (lower fixed point) and is assigned the value of 0 °C.

You may add little water and continue to stir gently.

The themometric substance will start to rise and stop when it reaches room temperature. Mark the point but do not assign any value

Place the beaker on bunsen burner and boil the water. The themometric substance will continue to rise and remain constant at upper fixed point

This mark will corresponds to the steam point (upper fixed point) and is assigned the value of 100 °C.

Divide between the lower fixed point and upper fixed point into equal intervals. Then you can see the value of room temperature.

7 0

3 years ago