Answer:
Efficiency = 10.2 %
Explanation:
Given the following data;
Mass = 70 kg
Height = 50 m
Velocity = 10 m/s
We know that acceleration due to gravity is equal to 9.8 m/s².
To find the efficiency of energy conversion from potential to kinetic;
First of all, we would determine the potential energy;
P.E = mgh
P.E = 70 * 9.8 * 50
P.E = 34300 J
For the kinetic energy;
K.E = ½mv²
K.E = ½ * 70 * 10²
K.E = 35 * 100
K.E = 3500
Therefore, Input energy, I = 34300 J
Output energy, O = 3500 J
Next, we find the efficiency;
Efficiency = O/I * 100
Substituting into the formula, we have;
Efficiency = 3500/34300 * 100
Efficiency = 0.1020 * 100
Efficiency = 10.2 %
Some liquid is poured into a burette so that it reads 14cm³.50 drops were run each of volume 0.1cm³ What is the volume of the 50 drops. (4marks)
Answer:
V = 5 cm³
Explanation:
In this exercise the volume (Vo = 0.1 cm³) of each drop is indicated, requesting the volume of 50 drops
V = V₀ #_drops
V = 0.1 50
V = 5 cm³
Answer:
[tex]V_{50}=5cm^3[/tex]
Explanation:
From the question we are told that:
Volume of liquid in burette [tex]V_b=14cm^3[/tex]
Volume of drop of liquid [tex]V_d=0.1cm^3[/tex]
Number of drops [tex]n=50[/tex]
Generally the equation for volume of 50 drops V_{50} is mathematically given by
[tex]V_{50}=V_d*n[/tex]
[tex]V_{50}=0.1*50[/tex]
[tex]V_{50}=5cm^3[/tex]
Therefore the volume of the 50 drops
[tex]V_{50}=5cm^3[/tex]
if the voltage across a 12 ohm resistor is 4.0 volts. the current through the resistor is?
Answer:
Current = 0.33 Amperes
Explanation:
Given the following data:
Resistance = 12 ohm
Voltage = 4 v
To find the current;
Ohm's law states that at constant temperature, the current flowing in an electrical circuit is directly proportional to the voltage applied across the two points and inversely proportional to the resistance in the electrical circuit.
Mathematically, Ohm's law is given by the formula;
Voltage = current * resistance
Substituting into the formula, we have;
4 = current * 12
Current = 4/12
Current = 0.33 Amperes
why are dams have broader walls at the bottom?
What is the electric field strenght in units of N/C if the flux through a 2.0m by 1.0m rectangular surface is 396Nm2/C, if the electric field is uniform, and if the plane of the surface is at an angle of π/3 radians with respect to the direction of the field ?
Answer:
The appropriate answer is "396 N/C".
Explanation:
The give values are:
Rectangular surface,
[tex]\Phi_e=396 \ N.m^2/C[/tex]
[tex]a = 2 \ m[/tex]
[tex]b = 1 \ m[/tex]
Angle,
[tex]\theta =\frac{\pi}{3} \ radian[/tex]
Now,
The area of rectangle (A) will be:
= [tex]a\times b[/tex]
= [tex]2\times 1[/tex]
= [tex]2 \ m^2[/tex]
hence,
The electric field strength will be:
⇒ [tex]\Phi_e=E.A Cos \theta[/tex]
or,
⇒ [tex]E=\frac{\Phi_e}{ACos \theta}[/tex]
On putting the given values, we get
⇒ [tex]=\frac{396}{2\times Cos(\frac{\pi}{3} )}[/tex]
⇒ [tex]=\frac{396}{2\times 0.5}[/tex]
⇒ [tex]=\frac{396}{1}[/tex]
⇒ [tex]=396 \ N/C[/tex]
What is the wavelength of sound wave in air that has a temperature of 24.6°C that has a frequency of 440.8 Hz?
A. 465.40 m
B. 0.78 m
C. 17.92 m
D. 0.75 m
Samples of different materials, A and B, have the same mass, but the sample
of A is higher in density. Which statement could explain why this is so?
A. The sample of material A has greater volume than the sample of
material B.
B. The particles that make up material B have more mass than the
particles that make up material A.
C. The particles that make up material B are more closely packed
together than the particles that make up material A.
D. The particles that make up material A have more mass than the
particles that make up material B.
Answer:
B. The particles that make up material B have more mass than the
particles that make up material A.
Explanation:
What’s the name of the muscle indicated on the image below?
1.Tricep
2.Oblique
3.Quadricep
4.Trapezius
Answer:
Oblique
Explanation:
I think that's the answer I was told this but forgot if this is the right answer if not then sorry
A satellite is acted upon by a 10n force upwards and 20n force downwards. What is the net force acting on the satellite and what direction will it move in
Answer:
Net force = 10 N in downward direction
Explanation:
Given that,
Upward force = 10 N
Downward force = 20 N
Let downward is negative and upward is positive.
Net force = 10+(-20)
= -10 N
So, the net force is 20 N and it is acting in downward direction.
NEED HELP In which of the following scenarios is work done?Single choice.
(2 Points)
A weightlifter holds a barbell overhead for 2.5 s.
A construction worker carries a heavy beam while walking at constant speed along a flat surface.
A car decelerates while traveling on a flat stretch of road.
A student holds a spring in a compressed position.
Answer: b. A construction worker carries a heavy beam while walking at constant speed along a flat surface.
Explanation:
Answer:
A construction worker carries a heavy beam while walking at constant speed along a flat surface.
hope it is helpful to you
what is kinetic energy, in your own words but be more detailed about what you say.
Kinetic energy is the energy when a object is in motion. ... energy gets transferred to the object, The energy transferred is kinetic energy, and it depends on the mass and speed.
Explanation:
Electricity is converted into other forms of _________ such as heat, sound, or light.
Answer:
chemical i think
I hope this helped
Find the equivalent resistance of this
circuit.
Ri
R2
1002
2002
R3
600 12
Answer:
63016
Explanation:
Ri+R2+R3 this is called series circuit
Answer:
200
Explanation:
100+200=300
1/300+1/600=200
25. Suppose there is no unbalanced force acting on a moving object. How will
the object's motion continue?
A. The speed of the object will decrease.
B. The speed of the object will increase.
C. The speed of the object will remain the same.
D. The direction of the object's velocity will change.
Answer:
C
Explanation:
Grammar is probably one of the most important components of the sciences besides math.
no unbalanced forces means that there is no force left over that cause an acceleration. All the forces are balanced.
So the Speed will not decrease. Not A.
The speed will not increase. Not B
The direction will not be affected. Not D
The answer is C
Which of the following BEST describes what occurs in a fusion reaction?
A.
Two low mass nuclei are joined to form one nucleus.
B.
A single nucleus divides into two or more nuclei and gives off energy.
C.
Electrons are shared between the nuclei.
D.
A chemical reaction occurs between the nuclei.
Answer:
Two mass nuclei are joined to form one nucleus
Explanation:
As the name implies "fusion", it is the joining of lighter nucleus to form a heavier nucleus to produce energy
Two bears sit on a see-saw. The see-saw is 3.5 m in total
length with the fulcrum at the center. A 40 kg baby bear sits at the very end of one side. Where should the 120 kg father bear sit relative to the center to keep the see-saw balanced?
Answer:
Explanation:
For the see-saw to be balanced, take moment at the fulcrum:
40g * 3.5/2 = 120g * distance
distance = 1.167m from the center
define gravitational field intensity?
Explanation:
The strength of the gravitational field is known as gravitational field intensity. It is the gravitational force acting on a unit test mass.
what factors could enhance memory and kept constant? and why
To help make sure information goes from short-term memory to long-term memory, you can use memory-enhancing strategies. One strategy is rehearsal, or the conscious repetition of information to be remembered. Think about how you learned your multiplication tables as a child.
Proven ways to protect memory include following a healthy diet, exercising regularly, not smoking, and keeping blood pressure, cholesterol, and blood sugar in check. Living a mentally active life is important, too. Just as muscles grow stronger with use, mental exercise helps keep mental skills and memory in tone.
According to one study, mental stimulation like reading can help protect memory and thinking skills, especially as you age. The authors even suggest that reading every day can slow down the late-life cognitive decline. ... The act of reading helps to heighten overall brain function and increase memory.
Let's take a deeper dive into evidence-based exercises that offer the best brain-boosting benefits.
Have fun with a jigsaw puzzle. ...
Try your hand at cards. ...
Build your vocabulary. ...
Dance your heart out. ...
Use all your senses. ...
Learn a new skill. ...
Teach a new skill to someone else. ...
Listen to or play music.
I am pushing on a large box with 200N of force. Clint is pushing on the box with 200N of force in the opposite direction. Why won't the box move?
what is the symbol end unit for electric charge
Answer:
The SI unit of electric charge is the coulomb and is represented by the symbol C.
[tex] \large\sf \leadsto\pmb{ Symbol \: Unit \: For \: Electric \: Charge}[/tex]
[tex] \sf \blue {The \: SI \: unit \: of \: electric \: charge \: is \: coulomb \: which \: is \: also \: represented \: as \: C!}[/tex]
A student is holding a marble in his hand. What are the equal and opposite forces that are acting on it?
Answer:
Gravity and his hand
Explanation:
What type of lens is used in the viewfinder of a simple camera and why? (Concave or convex)
Answer:
convex
sorry if this is wrong
True or False: A higher vapor pressure (evaporates easily) corresponds to strong intermolecular forces. (dont answer)
anyways free p o i n ts...
Answer:
truuuuuuuuuuuuuuuuuuuuuuuuujuuuuuuuur
Answer:
true
Explanation:
I took a test this year and I know the answer
A wave is moving at the rate of 40 cm/s. Its wavelength is 5 cm. What is the frequency of the wave? INCLUDE THE CORRECT UNIT!
Answer:
Solution given:
velocity=40cm/s
wave length=5cm
we have
frequency =velocity/wavelength=40/5=8hertz.
the frequency of the wave is 8 hertz.
A body is thrown up with with velocity u.it reaches maximum height h. If velocity of projection is doubled the maximum height is..
Answer: 4h
Explanation:
Given
The body is thrown vertically upward with velocity u and reaches a height of h
The relation between u and h is given by
[tex]\Rightarrow v^2-u^2=2as\\[/tex]
Put [tex]v=0,a=-g[/tex] in above equation
[tex]\Rightarrow 0-u^2=2(-g)h\\\\\Rightarrow h=\dfrac{u^2}{2g}[/tex]
If the velocity of projection is doubled i.e. 2u
[tex]\Rightarrow h'=\dfrac{(2u)^2}{2g}\\\Rightarrow h'=4\times \dfrac{u^2}{2g}\\\\\Rightarrow h'=4h[/tex]
The maximum height becomes 4h
PLS HELP
Light of wavelength A and frequency fpasses through a single slit of width a. A diffraction pattern is observed on a screen at a distance x from the slit. Which change will decrease the width of the central maximum?
A. Decrease the frequency of the light
B. Decrease the wavelength of the light.
C. Decrease the width of the slit.
El siguiente esquema representa un objeto con un volumen de 2cm^3 sumergido en un recipiente que contiene agua. La densidad del agua es 1 g/cm^3 . Si solo la mitad del objeto se encuentra sumergido, el valor de la masa del agua desalojada por el objeto es de:
Answer:
Ver explicación
Explanation:
Según los principios de Arquímedes, el empuje hacia arriba de un objeto sumergido en un fluido es igual al peso del fluido desplazado.
Por eso
Empuje hacia arriba = volumen del objeto * densidad del fluido * aceleración debida a la gravedad
Empuje hacia arriba = 2 * 10 ^ -6 / 2 * 1 * 10 ^ 3 * 10
Empuje hacia arriba = 0.01 N
Desde;
Empuje hacia arriba = peso del fluido desplazado
peso del fluido desplazado = 0.01 N
Masa de fluido desplazado = 0.01 N / 10 = 1 * 10 ^ -3 Kg o 1 g
Which would not be a reason for using wind power?
O Wind power has been created in areas where the wind is fast and consistent to provide consistent power.
O Wind power produces no pollution whatsoever.
O Wind power requires much less capital than other forms of alternative energy.
O Wind cannot be transported or used directly.
Two students go to play basketball. They notice the ball is flat (it won't bounce). They decide to pump it up with air. After it is pumped with air, will the ball have more, less, or the same amount of mass as before air was added?
A. The ball has less mass after being pumped with air.
B.Cannot determine unless we measure the mass.
C.The ball has more mass after being pumped with air.
D. The ball has the same amount of mass after being pumped with air.
Justify your answer
The ball has more mass being pumped with air. So, option (C) is correct answer.
What is mass?In physics, mass is a quantitative measurement of inertia, a basic characteristic of all matter. It essentially refers to a body of matter's resistance to changing its speed or location in response to the application of a force. The change caused by an applied force is smaller the more mass a body has. The kilogram serves as the unit of mass in the International System of Units (SI).
As the amount of air is added to the basketball by pumping it up with air, the mass of air is also added with the basketball. Hence, the ball has more mass now.
Learn more about mass here:
https://brainly.com/question/19694949
#SPJ2
explain why does the bowling ball decelerate as it travels along the lane
The main cause of this is Friction. The more oil that is laid down, the less friction there is between the ball and the lane surface. The less friction, the harder it is for the bowler to send the ball in a curved path imparted by the spin that the bowler puts on the ball at the instant of release.
Which answer is consistent with a replacement of light bulb that will increase
the intensity (brightness) of the light in a room
Answer:
What increases the brightness of a light bulb?
Increasing the voltage increases the brightness of the bulb. When a bulb in a series circuit is unscrewed all bulbs in the circuit go out. Increasing the number of bulbs in a series circuit decreases the brightness of the bulbs. ... Bulbs in parallel are brighter than bulbs in series.