Answer:
it is used because
It occupies less spaceheavy loads are easily movedminimum of effort is usedit is a bit lighter than screw jacks.They are also less likely to jam due to rust in the screw thread.
Hydraulic jacks are often used to lift elevators in low and medium rise buildings.
A hydraulic jack uses a liquid that is forced into a cylinder by a pump plunger.
2. A solid sphere and a solid cylinder, both uniform and of the same mass and radius, roll without slipping at the same forward speed. It is correct to say that the total kinetic energy of the solid sphere is A) more than the total kinetic energy of the cylinder. B) less than the total kinetic energy of the cylinder. C) equal to the total kinetic energy of the cylinder.
Research have found that other than for reasons of hunger, American women eat when they are depressed ,whereas Japanese women eat because of social demands.They found no significant differences between american and japanese men. These results demonstrate that ________ and _______ must be taken into account when studying why and under what circumstances people eat.
Answer:
culture
food
Explanation:
The above mentioned studied the interaction between food and culture. Food habits reflect different meanings in different cultures. As per the question, the United States America and Japan are two countries far away from each other, which have distinct cultures and gave rise to different eating norms. However, the impact of media have been shaping the eating patterns around the globe, which have brought different food and cultures together.
Which of the following is a TRUE
statement about states of matter?
A. Most matter on Earth exists as a solid, liquid, or gas.
B. Plasma, the fourth state of matter, is abundant on Earth.
C. Matter never changes from a solid to a liquid or a gas.
D. Most matter in the universe is liquid.
The statement that is the most true regarding the states of matter is the first statement.
A. Most matter on Earth exists as a solid, liquid, or gas.
This is correct since most of the matter on Earth exists in those 3 states, meanwhile plasma is not a state that most of matter on earth is found in since it is mostly associated to stars and the external galactic regions.
Therefore, B is incorrect.
C is false, since almost of all of the matter on earth can transform and change through each of the 3 states of matter, solid, liquid, and gas.
D is false since most of the matter in universe is actually made out of plasma instead of a liquid. In fact, over 99% of the known universe's matter is said to consist of plasma.
Matter can be defined as the material substance which constitutes the observable nature. Most matter on Earth exists as a solid, liquid, or gas. Plasma is also the state of matter found in daily life. The correct option is A.
What are states of matter?All the materials which we see in our daily lives are made up of matter. Matter can be classified into different states such as solid, liquid and gas based on the intermolecular forces and the arrangement of particles. All the three states of matter can be converted from one form to another.
The molecules of solid are tightly packed and they have strong intermolecular forces which also has a definite shape and volume. The liquids have weak intermolecular forces than the solids and it acquire the shape of the vessel.
The intermolecular forces in gases are negligible and they do not have any fixed shape or volume.
Thus the correct option is A.
To know more about states of matter, visit;
https://brainly.com/question/1134312
#SPJ2
A polonium isotope with an atomic mass of 211.988868 u undergoes alpha decay, resulting in a daughter isotope with an atomic mass of 207.976652 u. Ignoring any recoil of the daughter, find the kinetic energy of the emitted alpha particle in megaelectronvolts (MeV).
Answer:
K = 9.53 MeV
Explanation:
The kinetic energy that the alpha particle has emitted, is the energy in excess after removing the resting energy of the atoms and the helium nucleus that forms the alpha particle
Since energy and masses are related and cannot be
m₀ c² = [tex]m_{f}[/tex] c² + m_He c²+ K
K = c² (m₀ - m_{f} - m_He)
the mass of the Helium atom is 4 u
K = (3 10⁸)² (211,988868 -207.976652 - 4,002) 1,661 10⁻²⁷
K = 14,949 10⁻¹¹ (0.0102)
K = 1,527 10⁻¹² J
let's reduce 1 J = 6,242 10¹² MeV
K = 9.53 MeV
Una masa de 0,5 kg está sobre una pendiente inclinada 20º sujeta mediante una cuerda paralela a la pendiente que impide que deslice. Si no hay rozamiento, ¿qué fuerza hace la cuerda?
Answer:
4.61 N
Explanation:
masa = 0.5 kg
ángulo de inclinación = 20°
Peso normal de la masa = mg
donde m = masa
g = aceleración debido a la gravedad = 9.81 m/s^2
Peso normal = 0.5 x 9.81 = 4.905 N
Si la masa se mantiene en su lugar mediante una cuerda paralela al plano, y no hay fricción en la masa, entonces
La fuerza sobre la cuerda = peso normal x cos ∅
donde ∅ = 20 °
La fuerza sobre la cuerda = 4.905 x cos 20°
==> 4.61 N
HELP!?
Convert 107 km/h into m/s.
Answer: 29.72
Explanation:
you multiply the number by 5 then divide by 18=
107x5= 535
535/18= 29.72
A series circuit is shown in the diagram below. What is the potential drop across R₁? (R₂ = 20 Ω, R₂ = 40 Ω, R₃ = 60 Ω, V = 60 V) (Ohm's law: IR)
Answer:
Option B. 10 V.
Explanation:
The following data were obtained from the question:
Resistor 1 (R₁) = 20 Ω
Resistor 2 (R₂) = 40 Ω
Resistor 3 (R₃) = 60 Ω
Potential difference (V) = 60 V
Next, we shall determine the total resistance of the circuit.
The circuit is in series connection. Therefore the total resistance (R) can be obtained by adding up R₁, R₂ and R₃ together as shown below:
R = R₁ + R₂ + R₃
R = 20 + 40 + 60
R = 120 Ω
Therefore, the total resistance in the circuit is 120 Ω
Next, we shall determine the current flowing in the circuit.
Note: The same current will flow through each resistor since they are in series connection.
The current flowing in the circuit can be obtained as follow:
Potential difference (V) = 60 V
Total resistance (R) = 120 Ω
Current (I) =..?
V = IR
60 = I x 120
Divide both side by 120
I = 60/120
I = 0.5 A
Therefore, the current flowing in the circuit is 0.5 A
Now, we can calculate the potential drop across R₁ as follow:
Resistor 1 (R₁) = 20 Ω
Current (I) = 0.5 A
Potential difference cross R₁ (V₁) =.?
V₁ = IR₁
V₁ = 0.5 x 20
V₁ = 10 V
Therefore, the potential difference across R₁ is 10 V.
Consider that each tick mark represents 1 mile on the vector grid, use the Gizmo to simulate the following scenario: Imagine that a hiker walked 6 mi SE and then 4 mi N. Find the sum of the vectors. Which of the following best describes the general direction that the blue line points?
a) south
b) west
c) east
d) cannot be determined from this information
Answer:
The best description of the general direction that the blue line points is East direction
Answer:
c. east
Explanation:
If you are asked to modify the robots or drones that are currently used , what kind of modifications you would do and suggest any two fields where it can be used.
Explanation:
In recent times of pandemic, robots can be use as replacement of labor in the industries. Mundane tasks can be programmed in their system so that they can used readily.
Drones can used delivery for essential goods and services, so that human interference can be least and the spread of virus can be curbed.
In a recent example, Argentina where aerial data has reportedly been used to accelerate the construction of emergency hospitals.
Tech A says that an overdrive gear ratio means the input gear turns faster than the output gear. Tech B says that overdrive ratios provide less torque output than underdrive ratios. Who is correct?
Answer:
Technician B only is correct
Explanation:
The gear ratio is the ratio of the output speed to the input speed such that an overdrive gear ratio of more than 1:1, having more speed per speed of engine rotation RPM
Overdrive ratios conditions is one where the vehicle wheels and speed is faster at a given engine rotation, such that there is fuel efficiency is increased as the engine rotation is low for a given speed and distance of travel.
Experimenting with free fall, Mariana observes that her baseball takes 1.5 s to travel the last 30m before hitting the ground. From what height above the ground did Mariana drop the ball?
Answer:
37.8 m
Explanation:
At point 0, the ball is at height y₀.
At point 1, the ball is at height 30 m.
At point 2, the ball is at height 0 m.
Given:
y₁ = 30 m
y₂ = 0 m
v₀ = 0 m/s
a = -10 m/s²
t₂ − t₁ = 1.5 s
Find: y₀
Use constant acceleration equation.
y = y₀ + v₀ t + ½ at²
Evaluate at point 1.
y₁ = y₀ + v₀ t₁ + ½ at₁²
30 m = y₀ + (0 m/s) t₁ + ½ (-10 m/s²) t₁²
30 = y₀ − 5t₁²
Evaluate at point 2.
y₂ = y₀ + v₀ t₂ + ½ at₂²
0 m = y₀ + (0 m/s) t₂ + ½ (-10 m/s²) t₂²
0 = y₀ − 5t₂²
y₀ = 5t₂²
Substitute:
y₀ = 5 (1.5 + t₁)²
y₀ = 5 (2.25 + 3t₁ + t₁²)
y₀ = 11.25 + 15t₁ + 5t₁²
30 = 11.25 + 15t₁ + 5t₁² − 5t₁²
30 = 11.25 + 15t₁
t₁ = 1.25
30 = y₀ − 5t₁²
30 = y₀ − 5(1.25)²
y₀ ≈ 37.8
You are observing the radiation from a distant active galaxy and you notice that the amplitude of the signal varies in strength regularly over a certain period. The maximum possible size for the source of this radiation can now be calculated from the:____________
Answer:
Period of the signal.
Explanation:
So, this question is all about a concept in physics or astronomy which is called or known as Radiation Astronomy and Galactic Nuclei that are active. This concept talks most about Quasars; a powerful radiating object which derives its power from black holes.
When You take a look at Quasars, we get the to know that the more you think you can see, the more they move away from us.
Thus, when "You are observing the radiation from a distant active galaxy and you notice that the amplitude of the signal varies in strength regularly over a certain period. The maximum possible size for the source of this radiation can now be calculated from the "PERIOD OF THE SIGNAL.
NB: not the amplitude but the period.
A uniform metre rod of 5 metre length is suspended horizontally by two strings P and Q.Pis attached 0.8 metre from one end and Q is attached 2 metre from the other end.Given that the weight of the rod is 110N. Calculate the tension in each string
Answer:
The tension in string P is 25 N, while that of Q is 85 N.
Explanation:
Considering the conditions for equilibrium,
i. Total upward force = Total downward force
[tex]T_{P}[/tex] + [tex]T_{Q}[/tex] = 110 N
ii. Taking moment about P,
clockwise moment = anticlockwise moment
110 × (2.5 - 0.8) = [tex]T_{Q}[/tex] × (3 - 0.8)
110 × 1.7 = [tex]T_{Q}[/tex] × 2.2
187 = 2.2[tex]T_{Q}[/tex]
[tex]T_{Q}[/tex] = [tex]\frac{187}{2.2}[/tex]
[tex]T_{Q}[/tex] = 85 N
From the first condition,
[tex]T_{P}[/tex] + [tex]T_{Q}[/tex] = 110 N
[tex]T_{P}[/tex] + 85 N = 110 N
[tex]T_{P}[/tex] = 110 - 85
[tex]T_{P}[/tex] 25 N
Therefore, the tension in string P is 25 N while that of Q is 85 N.
(a) Two microwave frequencies are authorized for use in microwave ovens: 900 and 2560 MHz. Calculate the wavelength of each. (b) Which frequency would produce smaller hot spots in foods due to interference effects
Answer:
a) wavelength for the two frequencies are 0.33 m and 0.12 m
(b) 2560 MHz
Explanation:
Given:
microwave frequencies are
900 and 2560 MHz
f1= 900MHz we need to convert it to Go so the unit will be able to be consistent
f1= 900MHz= 900× 10^6Hz
f2= 2560 MHz= 2560×10^6Hz
a)Calculate the wavelength of each
But we can calculate our wavelength λ using the below formula
λ=c/f
c which is the speed of light has a constant value of =3*10^8m/s
Then for the first frequency
λ=c/f =(3×10^8)/900×10^6
=0.33 m
=33 cm.
For the second frequency
λ=c/f = (3×10^8)/2560×10^6
=0.12 m
=12 cm
(b) Which frequency would produce smaller hot spots in foods due to interference effects
(b) 2560 MHz( has the smallest wavelength)
This is because a small wavelength microwave gives a pattern with which is interference with waves and have a closer hotspot
A boat floats in a lake. When the boat moves the force of resistance is proportional to the velocity of the boat. Initially the boat is at rest. A person walks from the stern to the bow of the boat. What will be the position of the boat long time after the person stopped moving?
Answer: Contant.
Explanation:
You are given that When the boat moves the force of resistance is proportional to the velocity of the boat. This means that the total momentum on the boat is equal to zero. Then the boat remains at a certain position.
When a person walks from the stern to the bow of the boat, the boat will tend to move in the opposite direction with equal magnitude of momentum. The magnitude of forces will thereby cancel out.
The person will be seen moving while the boat moves in the opposite direction.
If no external force is acting on the boat, the sum of the momentum of the person and the boat will be equal to zero. And the boat will remain at rest.
The position of the boat long time after the person stopped moving will therefore remain the same.
A robot standing on a cliff shoots a ball upwards with an initial speed of 30 m/s. What is the height of the cliff given that the ball reaches the bottom of the cliff 8 s after the shoot? (Take g = 10 m/s^2 and the height of the robot is negligible.)
A 25 m
B 45 m
C 80 m
D 145 m
Answer:
C 80 m
Explanation:
Given:
v₀ = 30 m/s
a = -10 m/s²
t = 8 s
Find: Δy
Δy = v₀ t + ½ at²
Δy = (30 m/s) (8 s) + ½ (-10 m/s²) (8 s)²
Δy = -80 m
The ball lands 80 m below where it started. So the height of the cliff is 80 m.
Bumper car A (281 kg) moving +2.82 m/s makes an elastic collision with bumper car B (209 kg) moving +1.72 m/s. What is the velocity of car A after the collision? Would greatly appreciate the actual answer!
Answer:
Hello There. ☆~\《--_^■^_--》\~☆ The final velocity of the car A is -1.053 m/s. For an elastic collision both the kinetic energy and the momentum of the system are conserved.
Hope It Helps!~ ♡
ItsNobody~ ☆
Given:
[tex]M_A = 281 \ kg \\\\ v_A= 2.82 \frac{m}{s}\\\\M_B = 209 \ kg \\\\ V_B = 1.72 \frac{m}{s}[/tex]
To find:
velocity=?
Solution:
Using the formula for the velocity of CAR after the collision:
[tex]\to V_A = \frac{V_A(M_A -M_B) +2 M_B V_B}{M_A+M_B}\\\\[/tex]
[tex]= \frac{2.82(281 - 209) +2 \times 209 \times 1. 72}{ 281+ 209}\\\\ = \frac{2.82(72) +718.96}{490}\\\\= \frac{203.04 +718.96}{490}\\\\= \frac{922.00}{490}\\\\= \frac{922}{490}\\\\=1.881 \ \frac{m}{s}[/tex]
Therefore, the answer is "[tex]\bold{1.881\ \frac{m}{s}}[/tex]"
Learn more about the velocity:
brainly.com/question/24376522
Select the type of energy involved in each step. You turn on the burner of a gas stove. The gas ignites. The gas warms the water in the pan.
Answer:
You turn on the burner of a gas or stove - mechanical energy.
The gas ignites - Chemical energy.
The gas warms the water in the pan - Thermal energy.
Which force is there between an ice skate and the ice
Do you think, are we need to learn Measurement in Physics. Explain how the measurement is necessary and inevitable in real life situations?
Answer:
Measurement is inevitable because in every single thing we do we measure.for instance, if you are a family of four,the food prepared will be less than the food prepared for a family of about 15 people.this is measurement.if not so,the food prepared will go waste.again, the drugs prescribed by the doctor is measured to avoid over dose or under dose of medication.this can be harmful to ones health
Determine whether or not each of the following statements is true. If a statement is true, prove it. If a statement is false, provide a counterexample and explain how it constitutes a counter-example.
A capacitor consists of two flat, metal plates with unequal areas. Each of the plates starts neutral, and then each plate is connected to a dierent terminal of a battery. After some time, the plates will have excess charge on them, and the magnitude of the excess charge on one plate will equal the magnitude of the excess charge on the other plate.
A. True
B. False
If a wire carries current, then it has a net non-zero charge in it.
A. True
B. False
Answer:
a) True b) True
Explanation:
a) a capacitor is made up of two flat plates and each one has a charge of the same sign, therefore the statement is true
b) the current is the flow of electrons per unit of time, therefore the charge is not zero, therefore the statement is True
Una tractomula se desplaza con rapidez de 69 km/h. Cuando el conductor ve una vaca atravesada enmedio de la carretera, acciona los frenos y se detiene 4 s después. Si la vaca estaba a 25 m de la tractomulacuando el conductor pisó el freno. ¿atropelló la vaca? Justifique su respuesta.
Answer:
Los datos que tenemos:
Rapidez: 69km/h
Tiempo que tarda en frenar = 4s.
Distancia inicial entre la tracto-mula y la vaca = 25m
Ok, la ecuación de desaceleración es:
D = (sf - si)/t
sf = velocidad final = 0m/s
si = velocidad inicial = 69km/h
t = tiempo = 4s
D = -69km/h/4s
ok, 1h = 3600s
D = (-69km/s)*1/(4*3600s) = -0.0048 km/s^2
Entonces la ecuación de aceleración es:
a(t) = -0.0048 km/s^2
Para la velocidad, integramos sobre el tiempo
v(t) = (-0.0048 km/s^2)*t + v0
donde v0 es la velocidad inicial, en este caso v0 = 69km/3600s = 0.0191km/s
v(t) = (-0.0048 km/s^2)*t + 0.0191km/s
Para la posición volvemos a integrar sobre el tiempo, esta vez suponemos la posición inicial igual a cero.
p(t) = (1/2)*(-0.0048 km/s^2)*t^2 + 0.0191m/s*t
Ahora, si p(t=4s) < 25m, esto implica que la tracto-mula no impacto con la vaca.
p(4s) = (1/2)*(-0.0048 km/s^2)*(4s)^2 + 0.0191km/s*4s = 0.038km
y 1km = 1000m
0.038km = 0.038*1000m = 38m
Entonces si, atropello a la vaca.
A loudspeaker at the origin emits a 130 Hz tone on a day when the speed of sound is 340 m/s. The phase difference between two points on the x-axis is 5.6 rad.What is the distance between these two points
Answer:
distance between two points having phase difference 5.6 rad is
Φ = 2.33 m
Explanation:
given
frequency, f = 130Hz
speed of sound in air, v = 340m/s
distance between two crust or through with phase difference 2[tex]\pi[/tex] = λ (wavelength)
phase difference = 5.6 rad
note: distance between two points having a phase difference = [tex]\frac{ \lambda }{2\pi }[/tex]
∴ distance between two points having phase difference of 5.6 rad is = [tex]\frac{ \lambda }{2\pi }[/tex] ×5.6
Recall
v = f × λ
speed = frequency × wavelength
wavelength = speed/frequency
λ = v/f
λ = 340/130 = 2.615 m
∴ distance between two points having phase difference 5.6 rad is = [tex]\frac{ 2.615 }{2\pi }[/tex] ×5.6 = 2.33 m
If three cars, each of mass 1000 kg , occupy the NE, SE, and SW corners, determine the coordinates of the CM of the loaded ferryboat relative to the center of the raft. Take the origin to be at the CM of the raft.
Answer:
Using X = sum( x's * mass)/sum( masses)
= [(0)*(6400)+ (-9.5*1000) + (9.5)*(1000) + (9.5)*(1000)]/(6400+1000+1000+1000)
= 1.01 m
Y = sum( y's * mass)/sum( masses)
= [(0)*(6400) + (9.5)*(1000) +(-9.5)*(1000) + (-9.5)*(1000)]/ (6400+1000+1000+1000)
= -1.01 m
Which of the following are double-displacement reactions? multiple answers
A. 2H2(g) + O2(g) -> 2H2O(g)
B. Zn(s) + 2HCI(aq) -> H2(g) + ZnCI2(s)
C. Ba(OH)2(aq) + 2HCIO4(aq) -> Ba(CIO4)2(aq) + 2H2O(I)
D. HNO3 (aq) + KOH (aq) -> H2O(I) + KNO3 (aq)
Answer:
C and D
Explanation:
A: is a simple composition
B: is a single replacement
C: C is a double displacement
D: is a double replacement
Answer:
The answers are C abd D.
Explanation:
Here,
A no. Is a combination or analysis chemical reaction.
B no.is a single displacement reaction as cl2 goes to zn.
C no. Is double displacement reaction.
D no. Is a double displacement reaction.
Hope it helps.....
Q. A train accelerates from 36 km/h to 54 km/h in 10 sec. (i) Acceleration (ii) The distance travelled by car.
u=10m/s
v=15m/s
acceleration=
v_u/ t
5/10
0.5
If y=5sin (3x -40)
Calculate the frequency and period
Answer:
0.477 Hz
2.09 s
Explanation:
y = A sin(ωx − φ)
A is the amplitude, ω is the angular frequency, and φ is the phase shift.
ω = 3 rad/s
f = ω / 2π ≈ 0.477 Hz
T = 1/f ≈ 2.09 s
One star has a temperature of 30,000 K and another star has a temperature of 6,000 K. Compared to the cooler star, how much more energy per second will the hotter star radiate from each square meter of its surface?
Answer:
The hotter star radiates 625 times more energy per second from each square meter of its surface
Explanation:
Temperature of the hotter star is 30000 K
temperature of the cooler star = 6000 K
From Stefan-Boltzmann radiation laws, for a non black body
P = εσA[tex]T^{4}[/tex]
where
P is the energy per second or power of radiation
ε is the emissivity of the body
σ is the Stefan-Boltzmann constant of proportionality
A is the area of the sun
T is the temperature of the sun
The sun can be approximated as a black body, and the equation reduces to
P = σA[tex]T^{4}[/tex]
For the hotter body,
P = σA([tex]30000^{4}[/tex]) = 8.1 x 10^17σA J/s
For the cooler body,
P = σA([tex]6000^{4}[/tex]) = 1.296 x 10^15σA J/s
comparing the two stars energy
==> (8.1 x 10^17)/(1.296 x 10^15) = 625
This means that the hotter star radiates 625 times more energy per second from each square meter of its surface
In this video, we see that a _____ magnetic field can create an electric current. In this video, we see that a _____ magnetic field can create an electric current. Changing Perpendicular Strong Dipole
Answer:
The correct option is (a) "Changing".
Explanation:
If a coil is placed in the magnetic field, due to the change in its magnetic flux an emf will induce in it. EMF is like voltage. So, due to the induced emf and current is induced in it. Hence, we can say that changing the magnetic field can create an electric current.
List the submultiples and multiple units of length, mass, and time with respect to real-life situations. How are these units are related to S I unit of the above mentioned physical quantity?
Answer:
Explanation:
In physics, there are two types of physical quantities namely the fundamental and the derived quantities. Fundamental quantities are independent quantities on which derived quantities depends on. Length, mass and time are examples of fundamental quantities.
The SI unit of length is meters. A meter is a multiple unit. Its submultiple units are centimetres (10⁻²metres), kilometres (10³metres), decimetres (10⁻¹metres) etc
The SI unit of mass is kilogram (kg). The only sub multiple unit used in real-life situation is grams.
1 kg = 100 grams
The SI unit of time is seconds. The multiple units are the minutes, hours, weeks, days and years.
1 minute = 60 seconds
1 hour = 3600 seconds
1 day = 24 * 3600 = 86,400 secs