A flashlight is connected to a dry cell of voltage 3.50 V. It draws 20.0 ma (1000 ma = 1A) what is the resistance?

1. Three kids in a parking lot launch a rocket that rises

Mnenie [13.5K]

Answer:

Average speed equals distance / time

380 / 40 = 9.5 m/s.

Explanation:

3 0

3 years ago

The _____ theory is the most accepted theory regarding the origin of the solar system. It suggests that our star, the Sun, was f

lyudmila [28]

The big bang theory is the most accepted theory regarding the origin of the solar system. It suggests that our star, the Sun, was first created by a cloud ofdust and gas.

3 0

3 years ago

Read 2 more answers

The specific heat of substance A is greater than that of substance B. Both A and B are at the same initial temperature when equa

Sonja [21]

Answer:

$m_A c_{pA} (T_{fA} -T) = m_B c_{pB} (T_{fB}- T)$

For this case, if we try to find the final temperature of A and B, we see that we will obtain an expression in terms of specific heats and masses, from the information given we know the relationship between specific heats, but we don't know the relationship that exists among the masses, then the best option for this case is:

d) More information is needed

(The relation between the masses is not given)

Explanation:

For this case we know the following info:

$c_{pA} > c_{pB}$

Where c means specific heat for the substance A and B.

We also know that the initial temperatures for both sustances are equal:

$T_{iA}= T_{iB}$

We assume that we don't have melting or vaporization in the 2 substances. So we just have presence of sensible heat given by this formula:

$Q = m c_p \Delta T$

And for this case we know that Both A and B are at the same initial temperature when equal amounts of energy are added to them, so then we have this:

$Q_A = Q_B$

And if we replace the formula for sensible heat we got:

$m_A c_{pA} \Delta T_A = m_B c_{pB} \Delta T_B$

And if we replace for the change of the temperature we got:

$m_A c_{pA} (T_{fA} -T_{iA}) = m_B c_{pB} (T_{fB}- T_{iB})$

And since $T_{iA}= T_{iB}= T$ we have this:

$m_A c_{pA} (T_{fA} -T) = m_B c_{pB} (T_{fB}- T)$

For this case, if we try to find the final temperature of A and B, we see that we will obtain an expression in terms of specific heats and masses, from the information given we know the relationship between specific heats, but we don't know the relationship that exists among the masses, then the best option for this case is:

d) More information is needed

(The relation between the masses is not given)

4 0

3 years ago

What’s important about physical health

coldgirl [10]

Answer:

Physical activity or exercise can improve your health and reduce the risk of developing several diseases like type 2 diabetes, cancer and cardiovascular disease. Physical activity and exercise can have immediate and long-term health benefits. Most importantly, regular activity can improve your quality of life.

Explanation:

<h2>hope it is helpful for you </h2><h2>keep smiling </h2>

4 0

2 years ago

Which statement best describes why some materials are NOT magnetic?

hammer [34]

B

paired electrons spin in opposite directions cancelling their magnetic fields

3 0

3 years ago