Answer:
16 s
Explanation:
From the question given above, the following data were obtained:
Mass (m) = 40 Kg
Velocity (v) = 4 m/s
Power (P) = 20 W
Time (t) =?
Next, we shall determine the energy. This can be obtained as follow:
Mass (m) = 40 Kg
Velocity (v) = 4 m/s
Energy (E) =?
E = ½mv²
E = ½ × 40 × 4²
E = 20 × 16
E = 320 J
Finally, we shall determine the time. This can be obtained as follow:
Power (P) = 20 W
Energy (E) = 320 J
Time (t) =?
E = Pt
320 = 20 × t
Divide both side by 20
t = 320 / 20
t = 16 s
Thus, the time is 16 s
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
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
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
how moment act when applying a force on the pedal of a bicycle
Answer:
Forces that the rider applies to the pedals, saddle and handlebars during speeding, hill climbing and starting are estimated from cine film records using elementary mechanics. The results are compared with force measurements obtained from an instrumented pedal. Pedal forces of up to three times bodyweight were recorded during starting. Handlebar loads were always significantly large.
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.
explain how conservation of mechanical energy occurs a kicking a ball
Durante su práctica un atleta recorre en línea recta una distancia de 900m en un tiempo de 170 segundos. ¿Cuál fue su rapidez promedio?
Answer:
Velocidad promedio = 5.29 m/s
Explanation:
Dados los siguientes datos;
Distancia = 900 m
Tiempo = 170 segundos
Para encontrar la velocidad media;
La velocidad se puede definir como la distancia recorrida por unidad de tiempo. La velocidad es una cantidad escalar y, como tal, tiene magnitud pero no dirección.
Matemáticamente, la velocidad viene dada por la fórmula;
[tex] Velocidad = \frac{distancia}{tiempo}[/tex]
Sustituyendo en la fórmula anterior;
[tex] Velocidad = \frac{900}{170}[/tex]
Velocidad = 5.29 m/s
Por lo tanto, la velocidad promedio del automóvil es 5.29 metros por segundo.
A sled with mass 11.00 kg moves in a straight line on a frictionless horizontal surface. At one point in its path, its speed is 4.00 m/s; after it has traveled a distance 3.00 m beyond this point, its speed is 7.00 m/s. Use the work-energy theorem to find the force acting on the sled, assuming that this force is constant and that it acts in the direction of the sled's motion.
Answer:
The magnitude of the force acting on the sled is 60.5 newtons.
Explanation:
The Work-Energy Theorem states that the work done by the external force applied on the sled ([tex]W[/tex]), in joules, is equal to the change of its translational kinetic energy ([tex]\Delta K[/tex]), in joules:
[tex]W = \Delta K[/tex] (1)
By definitions of work and translational kinetic energy we expand the equation above:
[tex]F\cdot s = \frac{1}{2}\cdot m\cdot (v_{2}^{2}-v_{1}^{2})[/tex] (1b)
Where:
[tex]F[/tex] - External force applied on the sled, in newtons.
[tex]s[/tex] - Travelled distance, in meters.
[tex]v_{1}, v_{2}[/tex] - Initial and final velocities, in meters per second.
If we know that [tex]m = 11\,kg[/tex], [tex]v_{1} = 4\,\frac{m}{s}[/tex], [tex]v_{2} = 7\,\frac{m}{s}[/tex] and [tex]s = 3\,m[/tex], then the external force applied on the sled is:
[tex]F = \frac{m\cdot (v_{2}^{2}-v_{1}^{2})}{2\cdot s}[/tex]
[tex]F = \frac{(11\,kg)\cdot \left[\left(7\,\frac{m}{s} \right)^{2}-\left(4\,\frac{m}{s} \right)^{2}\right]}{2\cdot (3\,m)}[/tex]
[tex]F = 60.5\,N[/tex]
The magnitude of the force acting on the sled is 60.5 newtons.
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
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#
Activity 1 MATCH IT
Directions: Match Column A to Column B. Write your answer on the space provided before the number.
COLUMN A
__1. Hiking
__2. Orienteering
__3. Zumba
__4. Volleyball
__5.badminton
COLUMN B
A. It is an outdoor navigational recreational activity using specially drawn and detailed maps.
B. Created through on-the –spot aerobics class using the non- traditional music.
C.Going on an extended walk for the purpose of pleasure and exercise.
D. Can be traced from the ingenuity of William J. Morgan in 1895 at Holyoke Massachusetts.
E. Games are held inside the gym to avoid the effect of air in the flight of the shuttle.
Answer:
1. A hiking
2. C
3. B
4. D
5. E
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.
How does the temperature affect the speed of sound?
Explanation:
The relation between the speed of sound and the temperature is direct. As the temperature increases, the speed of sound also increases. If the substance is heated up, its molecules moves faster. As a result they collide faster and hence the speed increases. There is a relation between the speed of sound and the temperature i.e.
[tex]v=331+0.61T[/tex]
Hence, this is the required solution.
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
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
what is the relationship between the energy of a wave and ruts frequency?
Answer:
Just as wavelength and frequency are related to light, they are also related to energy. The shorter the wavelengths and higher the frequency corresponds with greater energy. So the longer the wavelengths and lower the frequency results in lower energy. The energy equation is E = hν.
Explanation:
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.
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
Express 0.00005 s in µs
Answer:
0.00005 second =
50 microseconds
Time
0.00005
Second
50
Microsecond
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:
quicklime which is calcium oxide, is made by heathig limestone in a furnace as per the equation :
CaCO3(s)CaO(s)+CO2
7.00Kg of calcium oxide was formed. what mass of calcium carbonate was heated?
Answer:
h2 PRD algo trata gevbjjgcvnkoytewxc.
Answer:
12.5kg
Explanation:
The process is explained in the paper
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
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.
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.
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:
What is an example of a series circuit
Answer:
Explanation
The most famous and common example is Christmas tree lights. You can't tell easily by looking at them whether they are in series or parallel. But you sure know the difference when one of them burns out. When that happens, the whole string goes dead. No matter what you do (other than find out which bulb burned out) will not fix the problem.
Another example is anything that is temperature controlled. For example a furnace is controlled by a thermostat. When the room temperature reaches a certain point, the thermostat is constructed in a certain way so that it forms an open circuit and no current can flow through it. The furnace motor turns off and the furnace stops pumping hot air into a room.
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
mechanical energy that has been "lost" to friction has actually been destroyed.
Answer:
Yes
Explanation:
The friction is bigger than the mechanical energy so it kind off takes over the mechanical energy. but if the friction decreases mechanical energy can work on the object again
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
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