Answer:
Refraction of waves involves a change in the direction of waves as they pass from one medium to another. Refraction, or the bending of the path of the waves, is accompanied by a change in speed and wavelength of the waves.
Sonny took 16 seconds to finish a 100-m race. What was
Sonny's average speed in the race
Speed = Distance/Time
=> Speed = 100m/16s
=> Speed = 6.25m/s
=> Speed = 6.25 ms^-1
pahelp po ako.
1. Which of the following terms refers to energy in motion?
A. kinetic energy C. potential energy
B. light energy D. thermal energy
2. Which of the following is a type of energy gained due to its position?
A. kinetic energy C. gravitational potential energy
B. light energy D. thermal energy
3. How do you get the total mechanical energy of an object in a closed system?
A. Get the sum of the initial and final kinetic energy.
B. Get the sum of the initial and final potential energy.
C. Get the sum of the kinetic energy and the potential energy.
D. Get the difference between the kinetic energy and the potential energy.
4. Which of the following is the best set up to observe the conservation of mechanical energy?
A. A cart rolling down a wooden ramp.
B. A wooden block falling in a vacuum.
C. A volleyball falling from a tall building.
D. a paper plane being launched from a tower.
5. A big rock was dropped from the third floor of a building. What happens to the kinetic energy of the ball as it falls?
A. The rock’s kinetic energy increases.
B. The rock’s kinetic energy decreases.
C. The rock’s kinetic energy remains the same.
D. The rock’s kinetic energy cannot be identified.
6. A heavy metallic ball was rolled up on a frictionless ramp. What happens to the gravitational potential energy of the ball as it rolls up the ramp?
A. The ball’s gravitational potential energy increases.
B. The ball’s gravitational potential energy decreases.
C. The ball’s gravitational potential energy remains the same.
D. The ball’s gravitational potential energy cannot be identified.
7. A 2kg ball is elevated up a building, how much is its potential energy 10m from the ground?
A. 5J C. 98J
B. 20J D. 196J
For items 8 to 10, refer to the illustration below. A ball is dropped at point W and travels along a frictionless path to reach point Z.
8. At which point does the ball has greatest gravitational potential energy?
A. W C. Y
B. X D. Z
9. At which point does the ball has greatest kinetic energy?
A. W C. Y
B. X D. Z
10. What happens to the total mechanical energy of the ball as it travels from point W to point Z?
A. The total mechanical energy increases.
B. The total mechanical energy decreases.
C. The total mechanical energy remains the same.
D. The total mechanical energy cannot be determined.
For items 11 to 12, refer to the illustration below. A pendulum swings back and forth from its highest position to its lowest position and vice versa.
11. As a pendulum swings from its highest to lowest position, what happens to its gravitational potential energy and kinetic energy?
A. Both its GPE and KE increases.
B. Both its GPE and KE decreases.
C. Its GPE decreases but KE increases.
D. Its GPE increases but KE decreases.
12. What happens to the total mechanical energy of the bob as it swings back and forth if only force acting on it is the gravitational force?
A. The total mechanical energy increases.
B. The total mechanical energy decreases.
C. The total mechanical energy remains the same.
D. The total mechanical energy cannot be determined.
Four ball of masses 0.5 kg, 1 kg, 2 kg, and 5 kg were dropped simultaneously on top of a building with the height of 20 m. Ignoring the air resistance, the four balls reach the ground at the same time.
13. Which of the following balls has the greatest gravitational potential energy on top of the building?
A. The ball with the mass of 5 kg.
B. The ball with the mass of 2 kg.
C. The ball with the mass of 0.5 kg.
D. All the balls have the same potential energy.
14. Which of the following balls has the least kinetic energy on top of the building?
A. The ball with the mass of 5kg.
B. The ball with the mass of 1kg.
C. The ball with the mass of 0.5kg.
D. All the balls have the same kinetic energy.
15. Which of the following balls has the greatest total mechanical energy?
A. The ball with the mass of 2kg.
B. The ball with the mass of 1kg.
C. The ball with the mass of 0.5kg.
D. All the balls have the same total mechanical energy
4. An object is thrown from from the ground upward with an initial speed of 3.75 m/s. How long will the object be in the air before it lands on the ground?
Answer:
Explanation:
There's an easy way to answer this and then an easier way. I'll do both since I'm not sure what you're doing this for: physics or calculus. Calculus is the easier way, btw.
Going with the physics version first, here's what we know:
a = -9.8 m/s/s
v₀ = 3.75 m/s
t = ??
That's not a whole lot...at least not enough to directly solve the problem. What we have to remember here is that at the max height of a parabolic path, the final velocity is 0. So we can add that to our info:
v = 0 m/s. Use the one-dimensional equation that utilizes all that info and allows us to solve for time:
v = v₀ +at and filling in:
0 = 3.75 + (-9.8)t and
-3.75 = -9.8t so
t = .38 seconds. This is how long it takes to get to its max height. Another thing we need to remember (which is why calculus is so much easier!) is that at the halfway point of a parabolic path (the max height), the object has traveled half the time it takes to make the whole trip. In other words, if .38 is how long it takes to go halfway, then 2(.38) is how long the whole trip takes:
2(.38) = .76 seconds. Now onto the calculus way:
The position function is
[tex]s(t)=-4.9t^2+3.75t[/tex] The first derivative of this is the velocity function and, knowing that when the velocity is 0, the time is halfway gone, we will find the velocity function and then set it equal to 0 and solve for t:
v(t) = -9.8t + 3.75 and
0 = -9.8t + 3.75 and
-3.75 = -9.8t so
t = ,38 and multiply that by 2 to find the time the whole trip took:
2(.38) = .76 seconds.
A car moves with the speed of 40 km/hr for the first half and 60 km/hr
for Second half distance "What is the average distance of cars.
Answer:
50 km/h
Explanation:
[tex](40 + 60) / 2[/tex]
-> [tex]50[/tex] (km/h)
The search for black holes involves searching for The search for black holes involves searching for Group of answer choices single stars that emit large amounts of X-rays. a stellar core greater than 3 solar masses large spherical regions from which no light is detected. pulsars with periods less than one millisecond. pulsars that are orbited by planets.
Answer:
Large spherical regions from which no light is detected
Explanation:
A black hole is an object that has an extremely high density such that it possesses very powerful gravitational force that prevents the escape of all objects including light from it, and consumes nearby objects.
Due to the power of the gravitational force of a black hole, at the center, objects are infinitesimally compressed resulting in the inapplicability of the concept of space and time and the location is known as a singularity
Therefore, the search for black holes involves searching for large spherical regions from which no light is detected.
Un auto que acelera a razón de 2 m/S^2 ; Si para cierto tramo se observa que logra triplicar su rapidez en 6 s. ¿Cuál fue su rapidez al final de estos 6 segundos?
Answer:
12m/s
Explanation:
Using the equation of motion
v = u + at
Given that
u = 0m/s
a = 2m/s²
time t = 6s
Substitute the given values into the expression
v = 0 + 2(6)
v = 0+12
v = 12m/s
Hence the required velocity is 12m/s
Can somebody help me understand this
Do the data for the first part of the experiment support or
refute the first hypothesis? Be sure to explain your
answer and include how the variables changed in the
first part of the experiment.
Mechanical equivalent of heat
Answer:
Sample Response: The data for the first part of the experiment support the first hypothesis. As the height of the cylinder increased, the temperature of the water increased. At a greater height, the cylinder has more gravitational potential energy. This gravitational potential energy was completely converted to thermal energy, which increased the temperature of the water.
Explanation:
this the sample response from ED mechanical equivalent of heat lab.
Answer:
Sample response:
Explanation:
The data for the first part of the experiment support the first hypothesis. As the height of the cylinder increased, the temperature of the water increased. At a greater height, the cylinder has more gravitational potential energy. This gravitational potential energy was completely converted to thermal energy, which increased the temperature of the water.
Help me and I'll make u Brainliest and follow u
26. D. crushing the sugar cube and dissolving it in water.
27. A. atom
28. B. molecule
29. B. plum pudding model of Joseph John Thomson
30. B. He used cathode ray tubes which showed that all atoms contain tiny negatively charged subatomic particles or electrons.
31. D. protons and neutrons are relatively heavier than electrons.
Select the correct answer. The motion of a car on a position-time graph is represented with a horizontal line. What does this indicate about the car’s motion? A. It’s not moving. B. It’s moving at a constant speed. C. It’s moving at a constant velocity. D. It’s speeding up.
If the car's motion appears as a horizontal line on a position-time graph, it shows that as time changes, the car's position doesn't change.
This is just a complicated way to say that the car is not moving. (A)
Answer: It's not moving.
Explanation:
I got it correct on edmentum.
Using diagram 1.1 and diagram 1.2, compare the number of turn of the coils, the pattern of the iron fillings and the angle of deflection of the ammeter pointer
Answer:
The number of turns in the second coil is more than the coil 1.
Explanation:
The magnetic field lines are the imaginary path on which an isolated north pole moves if it is free to do so.
The tangent at any point to the magnetic field line, gives the direction of magnetic field at that point.
More be the crowd ness of magnetic field lines more is the strength of magnetic field.
Here the crowd ness of magnetic field lines is more in figure 2 , so the magnetic filed in figure 2 is more than 1. It shows that the number of turns in the second coil is more than the 1 and also the current in the coil 2 is more than 1 .
The 75.0 kg hero of a movie is pulled upward at a constant velocity by a rope. What is the tension on the rope?
Answer:
750 N
Explanation:
the tension on the rope is the weight of the hero
Clothes are flung to the sides of a round tub during the spin-cycle of a washing machine.If the tub's period of rotation is 0.2s and the tub's radius is 35cm,answer the related qestions below: (a)The frequency of roation (b)The circumference of rotation (c)The spinning of speed (d)The centripetal acceleration (e)The centripetal force of rotation if total mass rotated is 30kg (f)The power of washing machine
Answer:
Explanation:
First I need to tell you that I used .20 s for the period of rotation instead of just .2, and I used 30.0 kg for the mass instead of just 30. The reason being that both those numbers as stated in the problem only have 1 significant digit and that's not generally enough to get the accuracy you're looking for. Adding a 0 to the ends of each of those numbers doesn't change the value of the numbers, only the number of sig fig's in each. Beginning with a:
a. [tex]f=\frac{1}{T}[/tex] so [tex]f=\frac{1}{.2}[/tex] and f = 5.0 Hz
b. The circumference is the distance around the outside of the washer's drum. We need to find that, but before we do, I'm going to state the radius in meters instead of cm. 35 cm = .35 m. Therefore,
C = 2(3.1415)(.35) so
C = d = 2.2 m
c. The speed of the washer is found in d = rt, where r is the rate and our velocity and d is the distance around the outside of the drum (circumference). Therefore,
2.2 = v(.20) so
v = 11 m/s
d. The centripetal acceleration has an equation
[tex]a_c=\frac{v^2}{r}[/tex] so
[tex]a_c=\frac{(11)^2}{.35}[/tex] and
[tex]a_c=\frac{121}{.35}[/tex] so
[tex]a_c=350\frac{m}{s^2}[/tex]
e. The centripetal force has an equation
[tex]F_c=\frac{mv^2}{r}[/tex] and
[tex]F_c=\frac{(30.0)(11)^2}{.35}[/tex] and
[tex]F_c=[/tex] 1.0 × 10⁴ N
f. The equation for Power is
[tex]P=\frac{W}{t}[/tex] where W is work and W = FΔx (force times displacement). Therefore,
[tex]P=\frac{(1.0*10^4)(2.2)}{.20}[/tex] so
P = 1.1 × 10⁵ Watts
Why do scientists use science
Answer:
Firstly, science helps our understanding of the world around us. Everything we know about the universe, from how trees reproduce to what an atom is made up of, is the result of scientific research and experiment.
Scientists use the scientific method to collect measurable, experimental evidence in an experiment related to a term (often in the form of an if/then statement), the results aiming to support or differ a theory. In other words, scientific method helps scientists get accurate, repeatable results.
What is the net force on a remote controlled airplane if a force of 57.6N is applied West and a force of 95.7N is applied South?
Answer:
112 N at 239°
Explanation:
Applying,
Pythagoras theorem,
a² = b²+c².................. Equation 1
Where a = net force
From the question,
Given: b = 57.6 N, c = 95.7 N
Substitute into equation 1
a² = 57.6²+95.7²
a² = 3317.76+9158.49
a² = 12476.25
a = √12476.25
a = 111.7 N
a ≈ 112 N
Then the direction is given as
∅ = tan⁻¹(c/b)........... Equation 2
∅ = tan⁻¹(95.7/57.6)
∅ = tan⁻¹(1.66)
∅ = 58.9°
∅ ≈ 59°
Since the angle is in the third quadrant,
∅' = 59+180
∅ = 239°
Hence the right answer is
112 N at 239°
How do the rocks in the mantle move?
A. They do not move.
B. They move in convection currents.
C. They flow like water.
D. They move on top of the crust.
Answer:
b. they move in convection currents.
Explanation:
i learned this in 4th grade
Find the transformation matrix that rotates a rectangular coordinate system through an angle of 60 about axes equal angels with original three coordinate axes
Answer:
[tex]M = \left[\begin{array}{ccc}cos \ 60&0\\0&-sin \ 60\end{array}\right][/tex]
Explanation:
To find the matrix, let's decompose the vectors, the rotated angle is (-60C) for the prime system
x ’= x cos (-60)
y ’= y sin (-60)
we use
cos 60 = cos (-60)
sin 60 = - sin (-60)
we substitute
x ’= x cos 60
y ’= - y sin 60
the transformation system is
[tex]\left[\begin{array}{ccc}x'\\y'\end{array}\right] = \left[\begin{array}{ccc}cos 60&0\\0&-sin60\end{array}\right] \ \left[\begin{array}{ccc}x\\y\end{array}\right][/tex]x '
the transformation matrix is
[tex]M = \left[\begin{array}{ccc}cos \ 60&0\\0&-sin \ 60\end{array}\right][/tex]
what are MA and VR of a lever?
Explanation:
Mechanical advantage (MA) = Load/Effort. Velocity ratio (VR) = distance effort moves/ distance load moves in the same time
if an object is placed at the center of carvature of a convance mirror the image formed is called
Answer:
When the object is placed between centre of curvature and principal focus of a concave mirror the image formed is beyond C as shown in the figure and it is real, inverted and magnified.
A student sects a leaf of length 7.2 cm to draw. Her drawing is 28.8 cm in length. What is the magnification of the drawing?
a) x4
b) x207.36
c) x0.25
d) x36
Answer:
A) x4
Explanation:
Magnification is equal to image size divided by the actual size, or M = I/A.
The image size is the student's drawing, which is 28.8 cm, and the actual size is 7.2 cm. Divide them, and cancel out the units, and you should get:
28.8 cm/7.2 cm = 4
: Một mặt phẳng vô hạn tích điện đều, mật độ σ = 4.10-9 C/cm2, đặt thẳng đứng trong không khí. Một quả cầu nhỏ có khối lượng 8 g, mang điện tích q = 10-8 C treo gần vào mặt phẳng, sao cho dây treo lúc đầu song song với mặt phẳng. Lấy g = 9,8m/s2. Khi cân bằng, dây treo quả cầu hợp với mặt phẳng 1 góc bằng bao nhiêu?
Answer:
The angle is 16 degree.
Explanation:
A uniformly charged infinite plane, density σ = 4.10-9 C/cm2, is placed vertically in air. A small ball of mass 8 g, with charge q = 10-8 C, hangs close to the plane, so that the string is initially parallel to the plane. Take g = 9.8m/s2 . In equilibrium, by what angle does the string hanging from the ball make an angle with the plane?
Surface charge density, σ = 4 x 10^-9 C/m^2
charge, q = 10^-8 C
mass, m = 0.008 kg
Let the tension is the string is T and the angle is A.
[tex]T sin A = q E....(1)\\\\T cos A = m g .... (2)\\\\Divie (1) by (2)\\\\tan A =\frac{q E}{m g}\\\\tan A = \frac{10^{-8}\times 4\times 10^{-5}}{2\times 8.85\times 10^{-12}\times 0.008\times9.8}\\\\tan A = 0.288\\\\A = 16 degree[/tex]
Capacitance (C) is measured in farads, where 1 farad is equivalent to 1 coulomb per volt. Resistance (R) is measured in ohms, and 1 ohm is equal to 1 volt per ampère. The coulomb is defined as the amount of charge passing when a current of 1 ampère flows for 1 second. What is the unit of RC expressed in its simplest form?
When fundamental units are combined, they result in derived units. RC (which means Resistance Capacitance) is a derived unit and its unit in the simplest form is Coulomb per Ampere (C/A)
Given that:
Capacitance (C) [tex]\to[/tex] Farads (f)
and
[tex]1f = 1\frac CV[/tex] ----- 1 farad = 1 capacitance per volt
Resistance (R) [tex]\to[/tex] Ohms [tex]\Omega[/tex]
[tex]1 \Omega = 1\frac{V}{A}[/tex]
The unit of RC is the product of the unit of R by the unit of C.
i.e.
[tex]RC = 1f \times 1\Omega[/tex]
Substitute [tex]1f = 1\frac CV[/tex]
[tex]RC = 1\frac CV \times 1\Omega[/tex]
Substitute [tex]1 \Omega = 1\frac{V}{A}[/tex]
[tex]RC = 1\frac CV \times 1\frac VA[/tex]
Cancel out volts (V)
[tex]RC = 1\frac CA[/tex]
[tex]\frac CA[/tex] means Coulomb per Ampere
Hence, the unit of RC is Coulomb per Ampere.
Read more about units at:
https://brainly.com/question/10167613
What information does the period number give about an atom?
Answer:All of the elements in a period have the same number of atomic orbitals. For example, every element in the top row (the first period) has one orbital for its electrons. All of the elements in the second row (the second period) have two orbitals for their electrons.Explanation:
Answer:
It tells us the principle quantum shell in which the element lies in. In other words, it shows the total number of electron shells the atom has
Compared to the inertia of a 1-kilogram mass, the inertia of a 4-kilogram mass is
Explanation:
The inertia of a 4 kg mass is four times as great as a 1 kg mass.
What kind of waves are present during an earthquake?
Answer:
There are four main types of earthquake waves:
P-waves S-waves (which are body waves), Rayleigh waves Love waves (which are surface waves).HOPE IT HELPS!!
what is acceleration
[tex]\boxed{\large{\bold{\blue{ANSWER~:) }}}}[/tex]
[tex]\sf What \: is \: acceleration? \\ \\ \sf The \: rate \: of \: change \: of \: velocity \: of \: an \\ \sf object \: with \: respect \: to \: time \\ \sf is \: known \: as \: acceleration. [/tex]
Question 5 of 10
A 15 N force is applied to an object, which then accelerates at 5.0 m/s2. What
is the mass of the object?
A. 10 kg
B. 20 kg
C. 75 kg
D. 3.0 kg
Hi there!
[tex]\large\boxed{D. \text{ } 3.0 kg}}[/tex]
Use the following equation to solve:
F = ma, where:
F = Force (N)
m = mass (kg)
a = acceleration (m/s²)
Thus:
15 = 5m
15/5 = m
mass = 3 kg
What is the meaning of the word "force"?
Answer:
Explanation:
The word force has a precise meaning. A force is exerted on one object by another. The idea of a force is not limited to living things or non-living things. All objects (living and non-living) can apply a force on or to another object also all objects (living and non living) can be affected by forces.
The most powerful empire between the 1500s and 1600s was the __________ Empire.
A.
Ottoman
B.
Mauryan
C.
Roman
D.
Persian
Answer:
A
Explanation:
Answer:
Ottoman
Explanation:
siri told me after I asked
A glass tube in the shape of a letter J has the shorter limb sealed and the longer limb open. Mercury is poured into the tube until the levels in either limb is the same when the tube is vertical.In this position, the length of the air column in the sealed limb is 6.3cm.More mercury is then poured into the tube until the length of the trapped air column is 42cm.Calculate the difference in the levels of mercury in the limbs if a nearby mercury barometer reads 75.0cm and the reading of a nearby thermometer has not changed?
Answer:
35.4 cm
Explanation:
We have that when the level of mercury on either limb is the same, the pressure of the trapped air, P₁ = Atmospheric pressure
Also the initial height of the mercury in the tube = The reading of the barometer = 75.0 cm
The initial length of the air column, l₁ = 6.3 cm
The final length of the air column, l₂ = 4.2 cm (The length is expected to decrease due to compression)
The volume, V = l × A
Where;
A = The cross sectional area of the tube
Therefore, the volume of the air column is directly proportional to the length of the air column
∴ V ∝ l
According to Boyles law, we have;
P₁·V₁ = P₂·V₂
Where;
P₁ = The initial pressure in the air column before more mercury is added
V₁ = The initial volume occupied by the air in the air column
P₂, and V₂ are the final pressure and volume of the air column respectively
Given that V = l·A, we can write;
P₁·l₁·A = P₂·l₂·A
P₂ = P₁·l₁·A/(l₂·A) = P₁·l₁/(l₂) = P₁ × 6.3/4.2 = 1.5·P₁
The pressure in the air column after more mercury is added, P₂ = 1.5 × P₁
P₁ = Atmospheric pressure, therefore;
The pressure in the air column after more mercury is added, P₂ = 1.5 × Atmospheric pressure
Pressure = h·ρ·g
Where;
ρ = The density of the substance
g = The acceleration due to gravity
h = The height of the column of the fluid
Given that the density and the gravitational force, can be taken as constant, we have that the pressure of the fluid is directly proportional to the height of the fluid column
Therefore, when the pressure doubles, the height of the fluid column doubles, and when the factor of increase is 1.5, we have;
The final level of the mercury, h₂ = 1.5·h₁ = 1.5×75 cm = 112.5 cm
The initial length of the closed end of the J tube, [tex]h_{closed1}[/tex] = 6.3 cm + 75 cm = 81.3 cm
The final length of the mercury in the closed end, [tex]h_{closed2}[/tex] = 81.3 cm - 4.2 cm = 77.1 cm
The difference in the level of mercury, Δh = h₂ - [tex]h_{closed2}[/tex]
∴ Δh = 112.5 cm - 77.1 cm = 35.4 cm
The difference in the levels of mercury in the limbs, Δh = 35.4 cm
