All categories

3 years ago

Karina strikes a match to light a candle. Explain what type of reaction the burning match represents in terms of energy

2 answers:

8 0

A burning match represents an exothermic reaction. The chemicals release energy in the form of heat and light as the reaction progresses.

blsea [12.9K]3 years ago

5 0

Answer:

Burning match represents exothermic reaction.

Explanation:

Exothermic reaction:These are the reaction which releases energy into the surroundings.

Endothermic reaction:These are the reaction which absorbs energy from the surroundings.

Burning of the match stick is an Exothermic reaction.This is because amount of energy required to burn the match is very less than of the energy given out by the match on burning.

Input Energy < Output Energy

You might be interested in

A cylinder with a mass M and radius r is floating in a pool of liquid. The cylinder is weighted on one end so that the axis of t

Blizzard [7]

Answer:

acylinder whit is yoiyes

8 0

4 years ago

A student made the claim that a 4 gram paintball fired from a paintball gun at 90 m/s could have about the same kinetic energy a

Fiesta28 [93]

Answer:

I do agree with the student. Because imagene you have a tissue and a stick. And you throw them at the same speed , the stick will go farther because it' s heavier but the tissue would just blow around and not go forward because it is not heavy enought.

Explanation:

Hope this is correct have a terrific day.

5 0

3 years ago

A sun-like star is barely visible to naked-eye observers on earth when it is a distance of 7.0 light years, or 6.6 * 1016 m, awa

igomit [66]

Answer:

At a distance of 1376.49 candle emits 0.2 watt power

Explanation:

Distance between Sun and earth $6.6\times 10^{16}m$

Sun emits a power of $P=3.8\times 10^{26}watt$

Power emitted by candle = 0.20 watt

We know that brightness is given by

$B=\frac{P}{4\pi d^2}$

So $\frac{3.8\times 10^{26}}{4\pi (6\times 10^{16})^2}=\frac{0.20}{4\pi d^2}$

$3.8\times 10^{26}d^2=7.2\times 10^{32}$

$d^2=1.89\times 10^6$

$d=1376.49m$

So at a distance of 1376.49 candle emits 0.2 watt power

3 0

3 years ago

Identical isolated conducting spheres 1 and 2 have equal charges and are separated by a distance that is large compared with the

scoundrel [369]

Answer:

F = 0.1575 N

Explanation:

When the third sphere touches the first sphere, the charge is distributed between both spheres, then now the first sphere has only half of his original charge.

In this moment then

Sphere one has a charge = Q/2

Sphere three has a charge = Q/2

Now when the third sphere touches the second sphere again the charge is distributed in a manner that both sphere has the same charge.

How the total charge is Q = Q/2 + Q = 3/2Q, when the spheres are separated each one has 3/4Q

Sphere two has a charge = 3/4Q

Sphere three has a charge = 3/4Q

The electrostatic force that acts on sphere 2 due to sphere 1 is:

F = $\frac{kQ_{1}Q_{2} }{r^{2} }$

F= $\frac{K(Q/2)(3Q/4)}{r^{2} }$

how $\frac{KQ^{2} }{r^{2} }$ = 0.42

Then

F = $\frac{0.42*3}{8}$

F = 0.1575 N

3 0

3 years ago

A 75-hp (shaft output) motor that has an efficiency of 91.0 percent is worn out and is to be replaced by a high- efficiency moto

daser333 [38]

Convert the shaft ouput from HP to kW

Shaft output = 75HP = 55.93kW

1st: Finding for the power consumption based on 55.93kW output

Power consumption (Old) = 55.93kW / .910 = 61.46kW

Power consumption (New) = 55.93kW / .954 = 58.63kW

2nd: Total power used in kWh:

Power Used = Power consumption * load factor * Hours:

Power (Old) = 61.46kW * .75 * 4368 = 201343 kWh

Power (New) = 58.63kW * .75 * 4368 = 192072 kWh

Energy saved = 201343 kWh - 192072 kWh = 9,271 kWh

3rd: Calculating for the price:

Price = kW-Hr * $/kWh

Price (Old) = 201343kWh * $0.08/kWh = $16107.44

Price (New) = 192072 kWh * $0.08/kWh = $15365.76

Cost saved = $16107.44 - $15365.76 = $741.68/yr

4th: Setting up the cost equation:

Cost over time, F(t) = Motor_Cost + (Price * Number of Years, t)

Cost (Old) = 5449 + 16107.44*t

Cost (New) = 5520 + 15365.76*t

Equate the two to find for t when they cost equally:

5449 + 16107.44*t = 5520 + 15365.76*t

16107.44*t = 15365.76*t +71

16107.44*t - 15365.76*t = 71

741.68*t = 71

t = 71 / 741.68 = .095 years = 35 days

So the payback period is after 35 days.

6 0

3 years ago