Answer:
Power
step by step explanation:
A girl travels 50m in 12s and then another 30m in 5s .Calculate her average speed?
Answer:
4.71m/s
Explanation:
Average speed = Total distance travelled ÷ Total time taken.
80/17=4.71
4.71m/s
Answer:
Average speed = Total distance travelled ÷ Total time taken.In this question,
Total distance travelled = 50m + 30m= 80m.
Total time taken = 12s + 5s= 17s
So, Average speed would be 80 ÷ 17
= [tex]\frac{80}{17}[/tex]
= 4.71 m/s. or 4.71 meter per second.
1. Compared to most other metals, what properties do the alkali metals have? А low melting points and high densities B low melting points and low densities C high melting point and high densities D high melting points and low densities
Answer:
B. low melting points and low densities
Explanation:
Alkali metals are any of the monovalent elements found in Group IA of the periodic table. They readily lose their one valence electron to form ionic compounds with nonmetals. Examples of alkali metal are Potassium (K), Lithium (L), and Sodium (Na).
Compared to most other metals, the chemical properties that alkali metals have are low melting points (28.5°C) and low densities that is typically less than 1 grams per cubic centimeters.
a sphere of mass 5kg and volume 2×10-5completely immersed in water find the buoyant force exerted water
Answer:
Buoyant force exerted water = 0.196 Newton
Explanation:
Given:
Mass of sphere ball = 5 kg
Volume = 2 x 10⁻⁵
Find:
Buoyant force exerted water
Computation:
Buoyant force exerted water = Gravity due to acceleration x volume of object x density of given liquid
Buoyant force exerted water = 9.8 x 2 x 10⁻⁵ x 1000
Buoyant force exerted water = 0.196 Newton
A capacitor stores 7.77 x 10-7 J of
energy when 4.29 x 10-8 C of
charge is on the plates. What is the
voltage across the capacitor?
[?] V
No links please
Answer: [tex]36.22\ V[/tex]
Explanation:
Given
Energy in a capacitor [tex]E=7.77\times 10^{-7}\ J[/tex]
Charge [tex]Q=4.29\times 10^{-8}\ C[/tex]
Energy of a capacitor is given by
[tex]E=\dfrac{1}{2}CV^2=\dfrac{1}{2}QV\quad [\text{Q=CV}][/tex]
Insert the values
[tex]E=\dfrac{1}{2}QV\\\\\Rightarrow 7.77\times 10^{-7}=\dfrac{1}{2}\times 4.29\times 10^{-8}\times V\\\\\Rightarrow V=3.622\times 10\\\\\Rightarrow V=36.22\ V[/tex]
Thus, the voltage around the capacitor is [tex]36.22\ V[/tex]
A converging lens can be defined as __________
a lens that causes parallel light rays to bounce off the surface
a lens that allows parallel light rays to pass without changing direction
a lens that causes parallel light rays to separate from each other
a lens that causes parallel light rays to focus at a specific location
Answer:
a lens that causes parallel light rays to separate from each other
Answer:
a lens that causes parallel light rays to focus at a specific location
I took the test and got it right! :)
1. A vehicle of mass 1500 kg braked to a standstill from a
velocity of 24 m/s in 12 s.
i. Show that the deceleration of the vehicle was 2.0 m/s2.
ii. Calculate the resultant force on the vehicle.
Explanation:
i. Vi=24
Vf=0
t= -2
a=vf-vi/t =0-24/12 = -2m/S2
ii. F=ma = 1500×-2= -3000 N
what is the speed of a wave with a wavelength of 3.0 m and a period of 0.40 s?
please help me ..im begging you
Explanation:
let's assume that:
v1= 600ml=0,6l
T1=27°C= 300K
p1=700mmHG=93326Pa
T2=-20°C=253K
p2=500mmHg=66661
V2=?
p1V1/T1=p2V2/T2 => V2=p1V1T2/p2
V2= 93326*0,6*253/66661
V2=212,52l
name the device of measurement and write its used or its function?
Answer:
There is a lot of instruments used for measurement, may I ask which one are you referring to?
4. Một nguồn điện ba pha đối xứng nối hình sao, điện áp ba pha nguồn Up = 220V. Nguồn điện cung cấp cho tải 3 pha đối xứng nối tam giác. Biết dòng điện dây Id = 10A. Tính điện áp dây, dòng điện pha của tải và của nguồn.
Answer:
so you gotta bring the 5 and add to 7
Explain: What happens to the velocity of a stream as the size of the sediment increases?
Answer:
Also, as stream depth increases, the hydraulic radius increases thereby making the stream more free flowing. Both of these factors lead to an increase in stream velocity. The increased velocity and the increased cross-sectional area mean that discharge increases.
In Part l, the independent variable was
Answer:
The independent variable is the variable the experimenter manipulates or changes, and is assumed to have a direct effect on the dependent variable. ... The dependent variable is the variable being tested and measured in an experiment, and is 'dependent' on the independent variable.
In which of the following do two smaller atoms fuse to form a larger atom?
Fission.
Fusion.
Neither
Both
Answer:
Fusion
Explanation:
A chemical reaction can be defined as a reaction in which two or more atoms of a chemical element react to form a chemical compound.
On the other hand, a nuclear reaction can be defined as a reaction in which the nucleus of an atom is transformed by being joined (fusion) or split (fission) with the nucleus of another atom of a radioactive element.
This ultimately implies that, during fusion, two smaller atoms fuse to form a larger atom. Thus, fusion involves the joining of two smaller nuclei of atoms to form a single massive or heavier nucleus with the release of energy.
Additionally, the energy that holds the neutrons and protons found in the nucleus of an atom together is known as Nuclear energy.
The rhinestones in costume jewelry are glass with index of refraction 1.50. To make them more reflective, they are often coated with a layer of silicon monoxide of index of refraction 2.00. What is the minimum coating thickness needed to ensure that light of wavelength 576 nm and of perpendicular incidence will be reflected from the two surfaces of the coating with fully constructive interference
Answer:
[tex]T=62.9*10^{-9}[/tex]
Explanation:
From the question we are told that:
Index of refraction of Rinestones [tex]\gamma_1 =1.5[/tex]
Index of refraction of silicon [tex]\gamma_2 =2.0[/tex]
Wavelength [tex]\lambda=576nm=576*10^{-9}[/tex]
Let each layer have thickness T
Therefore
Total Thickness =2T
Generally the equation for Constructive interference is mathematically given by
[tex]2T=(m+0.5)\frac{l\lambda}{\gamma_2}[/tex]
Where
[tex]M=0[/tex]
[tex]2T=(0+0.5)\frac{576*10^{-9}}{2*2.0}[/tex]
[tex]T=62.9*10^{-9}[/tex]
A car is travelling at 60m/s. and brakes to a speed of 14m/s, in 2.7 seconds. What is the deceleration?
Answer:
by using v = u + at equation we can find "a"
14 = 60 - 2.7a
2.7a = 60 - 14
2.7a = 46
decceleration = 17.03
What happens when a negatively charged object A is brought near a neutral object B?
A.
Object B gets a negative charge.
Ο
O o
B.Object B gets a positive charge.
O C.
Object B stays neutral but becomes polarized.
D.
Object A gets a positive charge.
O
E.
Object A loses all its charge.
Reset
Next
Answer:
A.
Explanation:Object b will get a negative charge .
Three voltmeters V, V₁ and V₂ are connected as in
Figure 37.9. a If V reads 18V and V, reads 12V, what does V₂ read?
b If the ammeter A reads 0.5A, how much electrical energy is changed to heat and light in lamp L₁ in one minute? c Copy Figure 37.9 and mark with a + the positive terminals of the ammeter and voltmeters for correct
connection.
Answer:
a. V₂ = 6 V
b. 360 joules
c. The positive terminals of both the voltmeter and ammeter are connected to the positive terminal of the power source
Please see the attached drawing created with MS Visio
Explanation:
a. The voltmeter readings are;
V₁ = 12 V, V = 18 V
Given that the voltage reading, 'V', is the voltage reading across two loads with voltages, V₁ and V₂ connected in series, we have;
V = V₁ + V₂
V₂ = V - V₁
V₂ = 18 V - 12 V = 6 V
b. The reading of the ammeter, A, I = 0.5 A
The heat energy, Q = I·V·t
Where;
t = The time = 1 minute (60 seconds)
Therefore, for the lamp L₁, where V = 12 V, we have;
Q₁ = 0.5 A × 12 V × 60 s = 360 Joules
The amount of electrical energy changed into heat and light in lamp L₁, Q₁ = 360 joules
c. The positive terminals of the voltmeter and ammeter are connected to the positive terminal of the power source
Please see attached drawing created with MS Visio
Car B is being pushed by a force of 22000 N. If it has a mass of 1375 kg.,
what is the acceleration of this car?
Answer:
a = 16 m/s²
General Formulas and Concepts:
Dynamics
Newton's Law of Motions
Newton's 1st Law of Motion: An object at rest remains at rest and an object in motion stays in motion Newton's 2nd Law of Motion: F = ma (Force is equal to [constant] mass times acceleration) Newton's 3rd Law of Motion: For every action, there is an equal and opposite reactionExplanation:
Step 1: Define
Identify variables
[Given] F = 22000 N
[Given] m = 1375 kg
[Solve] a
Step 2: Find Acceleration
Substitute in variables [Newton's 2nd Law of Motion]: 22000 N = (1375 kg)aIsolate a: 16 m/s² = aRewrite: a = 16 m/s²A deer walks 17.0 m south and then 12.0 m north. Find both the magnitude of its displacement and the distance traveled.
A)
5.0 m, 29.0 m
B)
5.0 m, 5.0 m
C)
29.0 m, 29.0 m
D)
29.0 m, 5.0 m
Answer:
Explanation:
Displacement involves direction and distance. In this case, the deer has walked a distance of 17 + 12 = 29m but because of the South-then-North direction, the net displacement is only 17-12 = 5m.
So the answer is A) 5.0 m, 29.0 m
Displacement:-
17-12=5mDistance:-
17+12=29mWhy do we see different phases of the lunar cycle?
A) As the moon rotates around its axis, different sides of it become visible.
B) as the earth rotates its axis, people can see different sides of the moon.
C) as earth revolves around the sun, the moon is cast into different shadows by earth.
D) as the moon revolves around earth, the different amounts of the sunlit side faces earth.
Answer: The answer is: D) as the moon revolves around earth, the different amounts of the sunlit side faces earth.
Explanation: I have my ways ;>
Have a great day!
-Sunny
A car accelerates for 10 seconds. During this time, the angular
velocity of the wheels of the car increases from 10 rad/s to 25 rad/s.
What is the angular acceleration of the wheels during this time?
e
Answer:
the angular acceleration of the car is 1.5 rad/s²
Explanation:
Given;
initial angular velocity, [tex]\omega_i[/tex] = 10 rad/s
final angular velocity, [tex]\omega_f[/tex] = 25 rad/s
time of motion, t = 10 s
The angular acceleration of the car is calculated as follows;
[tex]a_r = \frac{\omega_f - \omega_i }{t} \\\\a_r = \frac{25-10}{10} = 1.5 \ rad/s^2[/tex]
Therefore, the angular acceleration of the car is 1.5 rad/s²
help me please
only if you really know
Assume R is measured in meters (m) and M in kilograms (kg). Then
R ² / (GM) = [m]² / ([N•m²/kg²] [kg]) = m•kg / N = m•kg / (kg•m/s²) = s²
so t ² is indeed proportional to R ²/(GM).
Your friend has informed you that his/her uncle has decided not to look after him anymore.Write to your friends uncle giving him at least two reasons why he should change his mind
Answer:
Cause you are their family and they need you. Do you wanna be someone who abandoned them or be the one they look to and dont dislike into adulthood. Also you signed onto this job no one said it was going to be easy but you making your life easier but harder for someone who is just a kid who still needs you.
why are circuit breakers used in parts of national grid ?
Answer:
To protect control circuits or small devices with insufficient cutting power
Explanation:
If a charge of 40kC flows through an electrical heater and the amount of energy converted into heat is 10MJ. Calculate the potential difference across the ends of the heater.
Answer:
Energy Transfer Quiz - Quiz
The diagram shows a heater above a thermometer. The thermometer bulb is in the position shown.
what is the mystery behind black hole
Well since the gravitational pull is so strong, nothing can escape from it which means we haven't been able to get close enough to really know everything about them. There's no way of knowing what truly goes on inside of them since there is no way out.
Answer:
A black hole is a region of spacetime where gravity is so strong that nothing—no particles or even electromagnetic radiation such as light—can escape from it. The theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole.
Explanation:
which forces are capable of affecting particles or objects from large distance
Answer:
only long-range force that affects all particles is the gravitational force.
Explanation:
In nature there are four fundamental forces: nuclear, weak, gravitational and electrical.
The last two are long-range, that is, the forces are zero for infinite distances, the current gravitational on all the particles and the electric one acts on the charged particles, without the chosen charge it is zero, the forces is also zero.
Consequently the only long-range force that affects all particles is the gravitational force.
Una masa de Hidrogeno ocupa 0.2 L a 100°C. Determine su volumen a 0°C, si la presión se mantiene constante. Como la presión y la cantidad de materia se mantienen constantes, podemos aplicar la ley de Charles
Answer:
0,146 L
Explanation:
Según la ley de Charles; el volumen de una determinada masa de gas es directamente proporcional a su temperatura a presión constante.
A partir de los datos proporcionados;
V1 = 0,2 L
T1 = 100 ° C + 273 = 373 K
V2 =
T2 = 0 ° C + 273 = 273 K
V1 / T1 = V2 / T2
V1T2 = V2T1
V2 = V1T2 / T1
V2 = 0,2 × 273/373
V2 = 0,146 L
how do you do question 2?
Answer:
Look at explanation
Explanation:
a) Weight is another term for how much gravity is on an object and can be calculated by using the local gravity*mass so in order to find weight divide 1200 by g
m= 1200/9.8= 122.45kg
b) We know Fnet=ma and Fnet=Fapp+Fresistivity so Fapp+Fresistivity=ma
Plug in values
500+Fresistivity=122.45*2
solve for Fresistivty= 244.9-500=-255.1N (the reason it is negative is because it is in the opposite direction
c)Power= ΔE/Δt and we also know ΔE=ΔWork so Power= ΔWork/Δt. If a person pulls harder, they have a greater force and since mass is constant, acceleration is greater and since the amount of time needed to cover A to B is reduced since x-x0=v0t+1/2at²(v0=0, when you solve for t it will be lower because acceleration increases). If t decreases than Power increases by inverse proportionality. Work =Fd if the amount of Force increases by distance travelled remains constant than work also increases so power will also increase.
A person skateboards at 3.25 m/s for 55.0 s. How far did he travel?
