All categories

3 years ago

QuesLUI 2 UI IU

Physics

1 answer:

Alika [10]3 years ago

3 0

Answer:

D) The given reaction is Exothermic, because energy is released

Explanation:

Here, given that Zinc is added to a beaker containing hydrochloric acid.

Also, the beaker gets warm.

⇒The energy is released in the form of heat.

EXOTHERMIC reactions are those type of reactions in which energy is released in the form of heat.

When the beaker gets warm, the reaction is exothermic in nature.

Hence, the given reaction is Exothermic, because energy is released

You might be interested in

A 100-W (watt) light bulb has resistance R=143Ω (ohms) when attached to household current, where voltage varies as V=V0sin(2πft)

Phantasy [73]

Complete Question

A 100-W (watt) light bulb has resistance R=143Ω (ohms) when attached to household current, where voltage varies as V=V0sin(2πft), where V0=110 V, f=60 Hz. The power supplied to the bulb is P=V2R J/s (joules per second) and the total energy expended over a time period [0,T] (in seconds) is $U = \int\limits^T_0 {P(t)} \, dt$

Compute U if the bulb remains on for 5h

Answer:

The value is $U = 7.563 *10^{5} \ J$

Explanation:

From the question we are told that

The power rating of the bulb is $P = 100 \ W$

The resistance is $R = 143 \ \Omega$

The voltage is $V = V_o sin [2 \pi ft]$

The energy expanded is $U = \int\limits^T_0 {P(t)} \, dt$

The voltage $V_o = 110 \ V$

The frequency is $f = 60 \ Hz$

The time considered is $t = 5 \ h = 18000 \ s$

Generally power is mathematically represented as

$P = \frac{V^2}{ R}$

=> $P = \frac{( 110 sin [2 \pi * 60t])^2}{ 144}$

=> $P = \frac{ 110^2 [ sin [120 \pi t])^2}{ 144}$

$U = \int\limits^T_0 { \frac{ 110^2* [sin [120 \pi t])^2}{ 144}} \, dt$

=> $U = \frac{110^2}{144} \int\limits^T_0 { ( sin^2 [120 \pi t]} \, dt$

=> $U = \frac{110^2}{144} \int\limits^T_0 { \frac{1 - cos 2 (120\pi t)}{2} } \, dt$

=> $U = \frac{110^2}{144} \int\limits^T_0 { \frac{1 - cos 240 \pi t)}{2} } \, dt$

=> $U = \frac{110^2}{144} [\frac{t}{2} - [\frac{1}{2} * \frac{sin(240 \pi t)}{240 \pi} ] ]\left | T} \atop {0}} \right.$

=> $U = \frac{110^2}{144} [\frac{t}{2} - [\frac{1}{2} * \frac{sin(240 \pi t)}{240 \pi} ] ]\left | 18000} \atop {0}} \right.$

$U = \frac{110^2}{144} [\frac{18000}{2} - [\frac{1}{2} * \frac{sin(240 \pi (18000))}{240 \pi} ] ]$

=> $U = 7.563 *10^{5} \ J$

7 0

3 years ago

What element has 3 valence electrons and 4 energy levels

Tems11 [23]

Gallium is the answer

6 0

3 years ago

When the sound from two sound waves goes up and down (loud, soft, loud, soft) it makes a distinctive sound pattern called beats.

djverab [1.8K]

The beats are actually two new sounds.

Their frequencies are (the sum of the original two frequencies) and (the difference of the original two frequencies).

The existence of the beats is the result of the difference in the frequencies of the original two sounds. <em> (b)</em>

8 0

3 years ago

Read 2 more answers

A galvanometer is used as a

agasfer [191]

Answer:

detecting and indicating an electric current

4 0

3 years ago

A red blood cell is 7 x 10-6 m in size. This means it is 7 __________ in size. What unit completes the sentence?

aalyn [17]

If a red blood cell is 7 x $10^-^6$ m in size, it means that such a cell is 7 microns or micrometer in size. The unit that completes the sentence will, thus, be microns or micrometer.

According to international system of measurement:

$10^{-1}$ m = decimeter

$10^{-2}$ m = centimeter

$10^{-3}$ m = millimeter
$10^{-6}$ m = micrometer or micron
$10^{-9}$ m = nanometer

Thus, a measurement of 7 x $10^-^6$ m is the same is 7 micons or 7 micrometer.

More on metric conversion can be found here: brainly.com/question/17767575

5 0

2 years ago