Explanation:
The voltage of the lamp, V = 240 V
Power of the lamp, P = 40 W
It is running for 62 hours.
The cost of running is $2.50k per KWH
Electric power is,
P = 40×62 Wh
= 2480 Wh
P = 2.48 kWh
At the rate of $2.5 per kWh
P = $6.2
So, the cost of running is $6.2 per kWh.
2. In a chemical reaction
a) The atoms of the reactants always stay together to form the products
b) The atoms of the reactants unbond, rearrange, and then rebond to form the products
c) New atoms are formed which combine to make the products
d) Some atoms disappear while others multiply to form the products
Answer:
what I think in my opinion is B
Hello all, can you please answer this? I am struggling with this. I need this by tommorow. Question is below:
Light waves of frequency 6 x 10^14 Hz have a wavlength of 3.75 x 10^-7 m in water. What is their speed in water?
[tex]c_{water} = 2.25\times 10^{8}m/s[/tex]
Explanation:
The speed of light in any medium is given by
[tex]c = \lambda \nu[/tex]
where [tex]\lambda[/tex] is the wavelength and [tex]\nu[/tex] is the frequency. In water,
[tex]c_{water} = \lambda_{water} \nu[/tex]
[tex]\:\:\:\:\:\:\:\:= (3.75\times 10^{-7}\:m)(6\times 10^{14})\:Hz[/tex]
[tex]\:\:\:\:\:\:\:\:= 2.25\times 10^{8}\:m/s[/tex]
What is the mass of a cart that has an acceleration of 10m/s^2 when a net force of 2000 N is applied to it?
Please I need the answer...
Answer:
200kg is the answer to the question
explain how conservation of mechanical energy occurs a kicking a ball
How can you increase efficiency of a simple machine??
Answer:
Efficiency can be increase by using rollers in conjunction with the inclined plane. Wedge. The wedge is an adaptation of the inclined plane. It can be used to raise a heavy load over a short distance or to split a log.
Explanation:
Hope it helps
What effect does the distance between Earth and the Sun have on Earth’s seasons?
Answer:
So actually, it is not so much the distance at a particular time that affects the seasons. It is a common misconception. It is in-fact the earths tilt. When we rotate around the sun, due to our tilt, the North and South of earth have different seasons. This is because when light is shining on to earth, because of Earths tilt, on one half the light shines more directly and on the other it scatters thus the different temperatures, causing season. Hope this helps.
Show your work please
Answer:
[tex] V = U + at[/tex]
Explanation:
Given the following data;
Initial velocity = 0 (since the stone is starting from rest).
Final velocity = 32 m/s
Acceleration = g = 10 m/s²
Time = 3.2 seconds
To show that the speed of the stone when it hits the ground is 32 m/s, we would use the first equation of motion;
[tex] V = U + at[/tex]
Where;
V is the final velocity. U is the initial velocity. a is the acceleration. t is the time measured in seconds.Substituting into the formula, we have;
[tex] 32 = 0 + 10*3.2[/tex]
[tex] 32 = 0 + 32 [/tex]
[tex] 32 = 32 [/tex]
Proven: 32 m/s = 32 m/s
would volcanic activity have a noticable impact on climate over the next 50 years?
Answer:
yes
Explanation:
The gases and dust particles thrown into the atmosphere during volcanic eruptions have influences on climate. ... Volcanoes have also caused global warming over millions of years during times in Earth's history when extreme amounts of volcanism occurred, releasing greenhouse gases into the atmosphere.
An elevator of 3 × 10^4N is raised to a height of 100m in 20s . The work done by electric motor is equivalent to ?
Answer:
we neglect the time data
A.All three bulbs will go out
B.Bulbs 2 and 3 will go out, but bulb 1 will remain lit
C. All three bulbs will go out
D. Bulb 3 will go out, but bulbs 1 and 2 remain lit
Answer:
(D)
Explanation:
When switch C is opened then, Current is not flowing across 3 So bulb 3 will go out.
But current is flowing across 1 and 2 bulb because their switch is closed
therefore bulb 1 and 2 will remain it.
Hence, option (D) will be correct.
A bus travels with a constant speed of 48km/h. How long will it take to travel 60km?
Answer:
It will take 1 hr and 15 mins.
Explanation:
Let's look at the speed equation:
s=d/t
We want to find the time, and we have the speed and the distance, so we rearrange the equation. t will be on one side and s and d will be on the other side.
t=d/s
t=60km/(48km/h)
t=1.25h
An airplane with constant speed 696 mph than another 40 minutes constant speed 804 mph what is distance it go?
Answer:
536 miles
Explanation:
If the airplane is running at a speed of 804 miles per hour, and covers a distance, x in a particular number of mile. The distance in mile can be gotten they the application of direct formula. Multiplying the speed by the time it took, and thus
804 mph * 40
Remember the time is in minutes and not hours, so, you convert it to hours.
804 * 40/60 hours =
536 miles
Amigos necesito que me ayuden a resolver esta gráfica :').
Answer:
ANO BA TO?(;-;)
Explanation:
miss the rage??
The three scientists credited with using all available data and correctly determing the sturcture of dna from many years of previous work are
Answer:
James Watson, Francis Crick, and Maurice Wilkins
Explanation:
The three scientists that used the available data ( x-ray images of DNA provided by Rosalind Franklin) to correctly determine the structure of DNA are : James Watson, Francis Crick, and Maurice Wilkins.
These scientists discovered the structure of DNA in 1953 and they received, and they receive a Nobel Prize in Physiology or Medicine for their discovery
Um comentarista de futebol certa vez comentou:"A bola bateu na trave e voltou duas vezes mais forte". Sabendo que quando a bola atinge a trave ela acerta com uma força chamada de ação e a outra trave acerta com outra força chamada de reação explique porque a frase documentalista soa errada.
Answer:
Por ela ter batido na trave, não tem como voltar 2x mais forte, por que toda ação correspondente a uma reação de igual intensidade, mas que atua no sentido oposto
Explanation:
A ship anchored at sea is rocked by waves that have crests Lim apart the waves travel at 70m/S, at what frequency do the waves reach the ship?
Question: A ship anchored at sea is rocked by waves that have crests 100 m apart the waves travel at 70m/S, at what frequency do the waves reach the ship?
Answer:
0.7 Hz
Explanation:
Applying,
v = λf............... Equation 1
Where v = velocity of the wave, f = frequency fo the wave, λ = wavelength of the wave
make f the subject of the equation
f = v/λ................. Equation 2
From the question,
Given: v = 70 m/s, λ = 100 m ( distance between successive crest)
Substitute these values into equation 2
f = 70/100
f = 0.7 Hz
Hence the frequency at which the wave reach the ship is 0.7 Hz
A 1000 kg car accelerates from rest at a rate of 10 m/s² for 3 seconds. A) what is the final velocity of the car?
Answer:
Explanation:
We don't need the mass of the car in the equation to solve for final velocity, since the values given for the acceleration and the time it took to accelerate to that velocity are given. The equation we need is the one for acceleration, which is
[tex]a=\frac{v_f-v_0}{t}[/tex] We are solving for final velocity, we know the initial velocity is 0 (starting from rest), and the time to complete this acceleration (10 m/s/s) is 3 seconds:
[tex]10=\frac{v_f-0}{3}[/tex] which is the same thing as saying
[tex]10=\frac{v}{3}[/tex] so
v = 30 m/s
If the amplitude of a sound wave is increased by a factor of four,how does the energy carry by the sound wave in each time interval change?
Answer:
The energy will be increased by a factor 16
Explanation:
Mathematically, we have it that the energy carried by the sound wave is directly proportional to the square of the amplitude
So we have it that;
E = k * A^2
where E is the wave energy
K is the constant value
A is the amplitude value
So;
If E1 = k * (A1)^2
E2 = k * (A2)^2
But A2 = 4A1
E2 = k * (4A1)^2
E2 = k * 16(A1)^2
Divide E2 by E1
E2/E1 = k/k * 16(A1)^2/(A1)^2
E2/E1 = 16
E2 = 16 * E1
so simply, the energy will be increased by a factor of 16
The equivalent resistances of two wires connected in series and in parallel are 25 ohm and 4 ohm respectively. Calculate the resistance of each wire.
Answer:
5ohms and 20ohms
Explanation:
Let the resistance of each wire be R1 and R2, if the equivalent resistance in series is 25 ohms, then;
R1 + R2 = 25 ...1
If the equivalent in parallel is 4 ohm, then;
1/R1 + 1/R2 = 1/4
R2+R1/R1R2 = 1/4
Cross multiply
4(R2+R1) = R1R2 ...2
From 1;
R1 = 25 - R2 ... 3
Substitute 3 into 2
4(R2+25-R2) = (25-R2)R2
4(25) = (25-R2)R2
100 = 25R2 - R2²
R₂² -25R₂+100 = 0
R₂² -20R₂-5R₂+100 = 0
R₂(R₂-20)-5(R₂-20) = 0
(R₂-5)(R₂-20)=0
R₂ = 5 or 20
Since R₁ = 25-R₂
R₁ = 25 - 5
R₁ = 20
Hence the resistances are 5ohms and 20ohms
HELP
Question 1 of 25
A boy throws a ball straight up with a speed of 21.5 m/s. The ball has a mass
of 0.19 kg. How much gravitational potential energy will the ball have at the
top of its flight? (Assume there is no air resistance.)
O A. 48.5J
B. 41.2J
O C. 43.9 J
O D. 37.5J
Answer:
Explanation:
Although there is absolutely NO regard for significant digits, I can help you with this, nonetheless.
The equation for Potential Energy is PE = mgh. We have everything but the height of the ball. We have to solve for that using a one-dimensional motion equation:
v² = v₀² + 2aΔx, where Δx is our displacement (the height we need for PE). Filling in and keeping in mind that at the max height of parabolic travel, the final velocity of the object is 0:
0 = (21.5)² + 2(-9.8)Δx and
0 = 462.25 - 19.6Δx and
-462.25 = -19.6Δx so
Δx = 23.58 m. Using this as the h in our PE equation:
PE = .19(9.8)(23.58) so
PE = 43.9 J, choice C.
Which of the following graph is used for determining the instantaneous velocity from the slope?
A. distance-time graph
B. x - t graph
C. both of these
D. none of these
Answer:
B. x - t graph
Explanation:
A position-time (x-t) graph is a graph of the position of an object against (versus) time.
Generally, the slope of the line of a position-time (x-t) graph is typically used to determine or calculate the velocity of an object.
An instantaneous velocity can be defined as the rate of change in position of an object in motion for a short-specified interval of time. Thus, an instantaneous velocity is a quantity that can be found by measuring the slope of a line that is tangent to a point on the graph.
Hence, the x - t graph also referred to as the position-time graph is used for determining the instantaneous velocity from the slope.
For example;
Given that the equation of motion is S(t) = 4t² + 2t + 10. Find the instantaneous velocity at t = 5 seconds.
Solution.
[tex] S(t) = 4t^{2} + 2t + 10[/tex]
Differentiating the equation, we have;
[tex] S(t) = 8t + 2 [/tex]
Substituting the value of "t" into the equation, we have;
[tex] S(5) = 8(5) + 2 [/tex]
[tex] S(5) = 40 + 2 [/tex]
S(5) = 42 m/s.
Answer:
B. x - t graph
Explanation:
Thus, an instantaneous velocity is a quantity that can be found by measuring the slope of a line that is tangent to a point on the graph. Hence, the x - t graph also referred to as the position-time graph is used for determining the instantaneous velocity from the slope.
a mass of 2kg has a kinetic energy of 16J.what is the momentum of the body?
Explanation:
mass - 2kg
energy - 16 j
2
k.e- 1/2mv
2
16j=1/2×2×v
2
16×2/2=v
2
16=v
√16=v
V=4m/s
then momentum =mv
= 2×4
= 8 kgm/s
When playing a game of disc golf, each throw to your target is considered to be a O Point O Stroke O Hit O Toss
Answer:
an o point i think
Explanation:
Find the acceleration a body whose velocity increases from 11m/s to 33m/s in 10 seconds
Answer:
I am not sure if this is the answer
acceleration: 2.2m/s
Explanation:
here
initial velocity(u): 11m/s
Final velocity(v): 33m/s
time taken(t): 10 s
now
a:v-u/t
or
acceleration:final velocity-initial velocity/time taken
or
a: 33-11/10
or
a:22/10, divide it
: a=2.2m/s#
The specitic heat capacity of oxygen is 918 J/kg °C. The specific heat capacity of water is 4181 J/kg °C. Which substance will require more energy to raise its temperature by 1°C?
Answer:
Water
Explanation:
Given the specific heat of oxygen is 918J/kg °C and the specific heat of water is 4181 J/kg °C.
Consider 1Kg mass of each substance.
Now 1 Kg of oxygen needs 918 J of energy to raise its temperature by 1 °C
Also, 1 Kg of water needs 4181 J of energy to raise its temperature by 1 °C.
Clearly water requires more energy when compared to oxygen.
Basically, specific heat capacity is the amount of energy required to raise the temperature of a 1 kg body by 1 °C.
This circuit has five bulbs (A, B, C, D, and E). Select which bulbs would turn off if bulb C was unscrewed.
Answer:
C, A and E
Explanation:
In theory you always assume that the prostive is going to the negtive and since C, A and E are in series they all will turn off will turn off
the force acting normally per unit area on the surface of the body is known as
ssooeorkgogogoogkrorooror
Answer:
ssooeorkgogogoogkrorooror
Explanation:
A sound wave takes 0.2 seconds to travel 306 meters.
What is the speed of sound in this material? Through
which of the materials in Figure 24.23 is the wave
traveling?
Answer:
1530 m/s
Explanation:
Given that :
Speed = distance / time
Travel time take = 0.2 s
Distance covered = 306 metres
The speed of sound in the material :
Speed = distance / time = 306 m / 0.2
Speed = 1530 m/s
At 10-10 s during the evolution of the universe,______
formed, which are elementary particles that make
up protons and neutrons
What’s in the blank ?
Answer: Quarks
Explanation:
Quarks are the elementary particles that make up protons and neutrons. If you want to be more specific, there's six types, but overall, it's just quarks.