What voltage is required to move 2A through 5Ω?
2. Why is alcohol thermometer not suitable to measure high temperature?
Answer:
Alcohol thermometers are used rather than mercury thermometers in very cold regions because alcohol has a lower freezing point than mercury. Pure ethanol freezes at -115 degrees C, while mercury freezes at -38 degrees C.
Explanation:
It is less durable because alcohol evaporates faster than mercury. It cannot measure high temperature because of a low boiling point. It wets the walls of the thermometer, which can adversely impact the accuracy of readings
an electric bulb is marked 40volts ,230w another bulb is marked 40w,110v
a.calculate the ratio of their resistance
b.the ratio of their energy
c.find the charge on each bulb
d.which of the two bulbs can hold enough .
Answer:
a. The ratio of their resistance is 2783:64
b. The ratio of their energy is 4:23
c. The charge on the first bulb is 5.75 C
The charge on the second bulb is [tex]0.\overline {36}[/tex] C
Explanation:
The voltage on one of the electric bulbs, V₁ = 40 volts
The power rating of the bulb, P₁ = 230 w
The voltage on the other electric bulbs, V₂ = 110 volts
The power rating of the bulb, P₂ = 40 w
a. The power is given by the formula, P = I·V = V²/R
Therefore, R = V²/P
For the first bulb, the resistance, R₁ = 40²/230 ≈ 6.96
The resistance of the second bulb, R₂ = 110²/40
The ratio of their resistance, R₂/R₁ = (110²/40)/(40²/230) = 2783/64
∴ The ratio of their resistance, R₂:R₁ = 2783:64
b. The energy of a bulb, E = t × P
Where;
t = The time in which the bulb is powered on
∴ The energy of the first bulb, E₁ = 230 w × t
The energy of the second bulb, E₂ = 40 w × t
The ratio of their energy, E₂/E₁ = (40 w × t)/(230 w × t) = 4/23
∴ The ratio of their energy, E₂:E₁ = 4:23
c. The charge on a bulb, 'Q', is given by the formula, Q = I × t
Where;
I = The current flowing through the bulb
From P = I·V, we get;
I = P/V
For the first bulb, the current, I = 230 w/40 V = 5.75 amperes
The charge on the first bulb per second (t = 1) is therefore;
Q₁ = 5.75 A × 1 s = 5.75 C
The charge on the first bulb, Q₁ = 5.75 C
Similarly, the charge on the second bulb, Q₂ = (40 W/110 V) × 1 s = [tex]0.\overline {36}[/tex] C
The charge on the second bulb, Q₂ = [tex]0.\overline {36}[/tex] C.
d. The question has left out parts
What allows a metal to be pounded into a flat shape?
As a light wave strikes a shiny surface like a piece of polished metal, it will be
refracted
reflected
absorbed
Please help!!!!!
Fusion produces less radioactivity than fission.
True or false
Answer:
False
Explanation:
Fusion doesn't produce more.
Help me on this please
Which statement compares the strengths of electric forces between particles of matter?
Please don't just guess for points, if your answer is wrong i'll report it.
A. Hydrogen bonds are stronger than ionic bonds but weaker than Van der Waals forces.
B. Metallic bonds are stronger than hydrogen bonds but weaker than ionic bonds.
C. Hydrogen bonds are weaker than Van der Waals forces but stronger than metallic bonds.
D. Metallic bonds are weaker than hydrogen but are stronger than ionic bonds.
B. Metallic bonds are stronger than hydrogen bonds but weaker than ionic bonds.
The statement is discussing the relative strengths of different types of electric forces that can exist between particles of matter.
Metallic bonds are formed by the sharing of electrons between atoms in a metal, and are considered relatively strong. Hydrogen bonds are formed between molecules that contain hydrogen and are relatively weak compared to metallic bonds.
Ionic bonds are formed between positively and negatively charged ions and are generally considered to be the strongest of these three types of bonds. Thus, the statement concludes that metallic bonds are stronger than hydrogen bonds but weaker than ionic bonds in terms of their relative strengths.
For more such question on hydrogen
https://brainly.com/question/2111051
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An object attached to one end of a spring makes 20 complete vibrations in 10s. Its frequency is:
O 2 Hz
.50 s
2 s
.50 Hz
Answer:
0.50 s
Explanation:
An electric toy with a resistance of 2.50\,\Omega is operated by a 3.00\,\text{V} battery. (c) How much energy was delivered to the toy [over four hours]?
Answer:
Energy = 51840 J = 51.84 KJ
Explanation:
The electrical energy delivered to the toy can be found out by the following formula:
[tex]Energy = (Power)(time)\\Energy = (VI)(t)\\Enegry = VIt\\[/tex]
where,
V = Voltage = 3 V
R = Resistance = 2.5 Ω
I = Current = V/R (Ohm's Law) = 3 V/2.5 Ω = 1.2 A
t = time = (4 h)(3600 s/1 h) = 14400 s
Therefore,
[tex]Energy = (3\ V)(1.2\ A)(14400\ s)\\[/tex]
Energy = 51840 J = 51.84 KJ
Helppppppl!!!!!!!!!!!
Answer:
I think deposition of C is the oldest deposit
A piece of steel is 11.5cm long at 22C. It is heated to 1221C, close to its melting point. How long is it, in cm, at the high temperature?
Answer:
The length at the final temperature is 11.7 cm.
Explanation:
We need to use the thermal expansion equation:
[tex]\Delta L=\alpha L_{0}\Delta T[/tex]
Where:
L(0) is the initial lengthΔT is the differential temperature, final temperature minus initial temperature (T(f)-T(0))ΔL is the final length minus the initial length (L(f)-L(0))α is the coefficient of linear expantion of steel (12.5*10⁻⁶ 1/°C)So, we have:
[tex]L_{f}-L_{0}=\alpha L_{0}(T_{f}-T_{0})[/tex]
[tex]L_{f}=L_{0}+\alpha L_{0}(T_{f}-T_{0})[/tex]
[tex]L_{f}=0.115+(12.5*10^{-6})(0.115)(1221-22)[/tex]
[tex]L_{f}=0.117\: m[/tex]
Therefore, the length at the final temperature is 11.7 cm.
I hope it helps you!
If a chemical reaction has a AH value of -125 kJ, it would be considered what?
Answer:
Exothermic Reaction
Explanation:
ENDOTHERMIC REACTION: A chemical reaction is considered endothermic if the energy is absorbed during the reaction. In other words, if the energy is required by the reactants to proceed with the reaction, then the reaction is endothermic.
The value of enthalpy change ΔH is positive in such reactions showing intake of energy.
EXOTHERMIC REACTION: A chemical reaction is considered exothermic if the energy is released during the reaction. In other words, if the energy is produced as a product of the reaction, then the reaction is exothermic.
The value of enthalpy change ΔH is negative in such reactions showing the release of energy.
Since, the value of ΔH = -125 KJ, is negative for the given reaction.
Therefore, it would be considered as Exothermic Reaction.
If it takes 35J to lift up an object to some height, then how much gravitational potential energy will that object have?
A girl runs 40m due south in 40 seconds an d then 20m due north in 10 secondsCalculate.
the average speed,
her average velocity .
in her change in velocity for the whole journey!
The average speed of the girl is 1.2 m/s.
Average velocity is defined as the trade in position or displacement (∆x) divided by the time durations (∆t) wherein the displacement takes place. The common velocity can be effective or negative depending upon the sign of the displacement. The SI unit of average velocity is meters per second (m/s or ms-1).
Given;
Total distance = 40 + 20 = 60 M
Displacement = 40 - 20 = 20 m south
total time = 40 + 10 = 50 seconds
Average speed = total distance / total time
= 60/50
= 1.2 m/s
average velocity = total displacement / total time
= 20 / 50
= 0.4 m/s due south.
Average velocity is calculated by means of dividing your displacement (a vector pointing out of your initial role in your final position) through the entire time; the average pace is calculated by way of dividing the overall distance you traveled by means of the total time.
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I need help plz!!! Please help...
Answer: 60
Explanation:
What does the object below model?
O A. The heart
O B. The skeletal system
C. The brain
O D. The lungs
Answer: c
Explanation: it is c because i used my brain to answer it
Answer: The Brain
Explanation:
Its the brain
How much energy does a 100-W light bulb use in 8.0 hours?
Energy is referred to heat here
Power=P=100WTime=t=8hEnergy be H
[tex]\\ \sf\Rrightarrow H=Pt[/tex]
[tex]\\ \sf\Rrightarrow H=100(8)[/tex]
[tex]\\ \sf\Rrightarrow H=800J[/tex]
As distance ________________ between two objects, gravitational force will _________________. *
1 point
a. increases, increase
b. increases, decrease
c. decreases. increase
Answer:
b. increases, decrease
Explanation:
Which benefit is provided by good flexibility?
A. less risk of injury
B. longer endurance
C. muscle growth
D. greater strength
Would the following reaction be endothermic or exothermic? Why?
CH4 + 02 --> CO2 + H2O + Energy
A. Exothermic because energy is a reactant
B. Endothermic because energy is a reactant
C. Endothermic because energy is a product
D. Exothermic because energy is a product
Answer:
D. Exothermic because energy is a product
Explanation:
ENDOTHERMIC REACTION: A chemical reaction is considered endothermic if the energy is absorbed during the reaction. In other words, if the energy is required by the reactants to proceed with the reaction, then the reaction is endothermic.
EXOTHERMIC REACTION: A chemical reaction is considered exothermic if the energy is released during the reaction. In other words, if the energy is produced as a product of the reaction, then the reaction is exothermic.
Hence, the correct answer for this question will be:
D. Exothermic because energy is a product
will give Brianliest answer. help.
consider a collusion in one dimension that invoves two objects of masses 4.5 kg and 6.2 kg the larger mass is originally at rest, and the smaller mass has an initial velocity of 16 m/s [E]. the final velocity of the larger object is 10.0 m/s [E]. calculate the final velocity of the smaller object after the collision.
Answer:6.2
Explanation:
someone please help I have no idea what to do
Answer:
10⁶ or 1000000
Explanation:
formula: frequency = velocity/wavelength = [tex]\frac{3.0x10^{8} }{3.0x10^{2}}[/tex]i'm not sure because the teacher probably wrote the question wrong.What kind of energy does an electromagnet use to pick up metallic objects?
Answer:
Magnetic energy is used by an electromagnet to pick up metallic objects
Explanation:
An electromagnet generates its own magnetic field in presence of electric current.
As an electric current is induced in an electromagnet , it magnetic dipole arrange themselves in order to behave as a magnet and hence generate magnetic field with a proper north and south. This leads to attraction of metallic object.
Hence, it can be said that Magnetic energy is used by an electromagnet to pick up metallic objects
A dog sits on a flat surface. If the dog has a mass of 13 kg, what is the normal force acting on it?
85 N
13 N
127 N
41 N
Answer:
127
Explanation:
f(n)=mg
(13)*(9.81)
127.4N
8. An electric force F exists between two objects, both having thecharge, q. If the charge on one object is doubled to 2q, the force
between the objects becomes
A. 1/4 F
B. 1/2 F
C. 2F
D. 4F
What effect does the Sun have on the ocean tides?
A.
The Sun does not have an effect on the ocean tides because it is
too far away.
B. The Sun warms the water, causing it to rise.
C. The gravitational pull of the Sun causes spring and neap tides.
D.the gravitational pull of the sun gravity is more powerful then the moons
Answer:
B
Explanation:
When the sun, moon, and Earth are in alignment at the time of the new or full moon, the solar tide has an additive effect on the lunar tide, creating extra-high high tides, and very low, low tides both commonly called spring tides.
how to calculate acceleration
Answer:
Acceleration (a) is the change in velocity (Δv) over the change in time (Δt), represented by the equation a = Δv/Δt. This allows you to measure how fast velocity changes in meters per second squared (m/s^2). Acceleration is also a vector quantity, so it includes both magnitude and direction.
Explanation:
hope it help mark me as brill please
Answer:
acceleration equals the change in velocity divided by time
Explanation:
Reflection, refraction, and diffraction
all cause light
waves to
A) bend
B) change direction
C)stand still
D)absorb energy
Answer:
B) change direction
Explanation:
Diffraction is the change of direction of waves that occurs when waves travel from one medium to another.
Reflection is the change of direction of waves when they bounce off of a barrier.
Refraction is the change of direction of waves that happens when waves pass from one medium to another.
Each of these are all the change in direction of waves.
Which chemical reaction is the fastest?
A. Mold grows on bread.
B. Bacteria make yogurt from milk.
C. Yeast produces air pockets in bread.
D. Baking soda produces bubbles when vinegar is poured on it.
Answer:
D. Baking soda produces bubbles when vinegar is poured on it.
Explanation:
Acetic acid = C₂H₄O₂
Baking soda = NaHCO₃
C₂H₄O₂ + NaHCO₃ → NaC₂H₃O₂ + H₂O + CO₂
When baking soda is added to vinegar, a chemical reaction will take place producing a huge amount of carbon-dioxide in the form of bubbles in the foaming mixture.