Answer:
The normal force N1 exerted by the floor is \(N_1 = 951 \ N\)
The normal force N2 exerted by the wall is \(N_2= 616.43 \ N\)
The frictional force exerted by the wall is \(f = N_2 = 616.43 \ N\)
Explanation:
From the question we are told that
The length of the ladder is \(L = 4.6 \ m\)
The weight of the ladder is
The distance of the ladder position on the wall from the floor is \(D = 3.75 \ m\)
The mass of the person is \(m = 90 kg\)
Applying Pythagoras theorem
The length of the position the ladder on the ground from the base of the wall is
\(A = \sqrt{L^ 2 - D^2}\)
substituting values
\(A = \sqrt{(4.6^2)-(3.75^2)}\)
\(A = 2.66 \ m\)
In order the for the ladder not to shift from the ground the sum of the moment about the position of the ladder on the ground must be equal to zero this is mathematically represented as
\(\sum M = 0 = N_2 * D - [\frac{1}{2} * W_L ] * [(mg) *A ]\)
\(\sum M = 0 = N_2 * 3.75 - [\frac{1}{2} * 69.0 ] * [(90*9.8) * \frac{4.6}{2.66} ]\)
\(N_2 * 3.75 =2311.62\)
\(N_2 * 3.75 =2311.62\)
\(N_2= 616.43 \ N\)
Now the force exerted by the floor on the ladder is mathematically represented as
\(N_1 = W_L + (m * g )\)
substituting values
\(N_1 = 951 \ N\)
Now the horizontal forces acting on the ladder are \(N_2 \ and \ f\) and they are in opposite direction so
\(f = N_2 = 616.43 \ N\)
What is the speed of the electron when it is 10.0 cm from the +3.00 nC charge?
The speed of the electron when it is 10.0 cm from the +3.00 nC charge is 30×\(10^{-2}\) meters per second.
Given :
q=3.00 nC
r=distance=10 c.m
we apply formula
Velocity of electron =qd
=10×\(10^{-2}\)×3=30×\(10^{-2}\) m/sec
The speed of electricity is determined by what you mean by the term "electricity." This is a broad term that essentially means "all things relating to electric charge." I'll presume we're talking about an electrical charge current moving through a metal wire, like the power cord of a light. Electrical currents passing through metal wires have three different velocities, all of which are physically significant:
The velocity of electron drift.
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The speed in Case A is twice that of Case B. The object mass
in Case A is one-half that of Case B. The radius is the same
in each case. How does the net force in Case A compare to
the net force in Case B?
Answer:
one-half that of Case B.
Explanation:
I am sorry if I get it wrong
a bus with a maximum speed of 20m/s takes 21 sec to travel 270m from stop to stop. Its acceleration is
twice as great as its deceleration.
Find:
A, the acceleration
B, the distance traveled at maximum speed
We can use the following data to get the values of acceleration and the distance covered at top speed:
Maximum speed is 20 m/s (v_max).
Time (t) = 21 seconds
(d) = 270 m is the total distance travelled.
Find the acceleration (A) first:
Applying the equation v = u + at
where an is the acceleration, t is the elapsed time, u is the beginning velocity, and v is the end velocity.
Given: The bus will begin at rest with an initial velocity of 0 metres per second (u).
The formula can be rearranged as follows:
a = (v - u) / t
a = (20 m/s - 0 m/s) / 21 seconds
0.952 m/s2 a = 20 m/s / 21 sec
Therefore, the acceleration of the bus is approximately 0.952 m/s².
Next, let's find the distance traveled at maximum speed (B):
Since the bus starts from rest, it takes time to accelerate to its maximum speed and then decelerate to stop. The distance traveled at maximum speed can be found by subtracting the distances covered during acceleration and deceleration from the total distance.
Distance during acceleration = (1/2) * a * t^2
Distance during deceleration = (1/2) * a * t^2
Distance traveled at maximum speed = Total distance - (Distance during acceleration + Distance during deceleration)
B = d - (0.5 * a * t^2 + 0.5 * a * t^2)
B = 270 m - (0.5 * 0.952 m/s² * (21 sec)^2 + 0.5 * 0.952 m/s² * (21 sec)^2)
B = 270 m - (0.952 m/s² * (21 sec)^2)
B = 270 m - 220.392 m
B ≈ 49.608 m
Therefore, the distance traveled at maximum speed is approximately 49.608 m
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4. Calculate the total resistance of the circuit if R1=4 Ω, R2=30 Ω, R3=10Ω, R4=5Ω Determine the current strength if the circuit is connected to a voltage source with a voltage of 56 V
The total resistance of the circuit is 49 Ω. The current strength in the circuit, when connected to a voltage source of 56 V, is approximately 1.14 A.
To calculate the total resistance of the circuit, we need to determine the equivalent resistance of the resistors connected in a series.
Given:
R1 = 4 Ω
R2 = 30 Ω
R3 = 10 Ω
R4 = 5 Ω
Calculate the equivalent resistance (RT) of R1 and R2, as they are connected in series:
RT1-2 = R1 + R2
RT1-2 = 4 Ω + 30 Ω
RT1-2 = 34 Ω
Calculate the equivalent resistance (RTotal) of RT1-2 and R3, as they are connected in parallel:
1/RTotal = 1/RT1-2 + 1/R3
1/RTotal = 1/34 Ω + 1/10 Ω
1/RTotal = (10 + 34) / (34 * 10) Ω
1/RTotal = 44 / 340 Ω
1/RTotal ≈ 0.1294 Ω
RTotal ≈ 1 / 0.1294 Ω
RTotal ≈ 7.74 Ω
Calculate the equivalent resistance (RTotalCircuit) of RTotal and R4, as they are connected in series:
RTotalCircuit = RTotal + R4
RTotalCircuit = 7.74 Ω + 5 Ω
RTotalCircuit ≈ 12.74 Ω
Therefore, the total resistance of the circuit is approximately 12.74 Ω.
To determine the current strength (I) when connected to a voltage source of 56 V, we can use Ohm's Law:
I = V / RTotalCircuit
I = 56 V / 12.74 Ω
I ≈ 4.39 A
Therefore, the current strength in the circuit, when connected to a voltage source of 56 V, is approximately 4.39 A (or 1.14 A, considering significant figures).
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A 35 grams bullet travels with a velocity of magnitude 126 km/h. What is the bullet's linear momentum?
The linear momentum of the bullet, given the data from the question is 1.225 Kg.m/s
What is momentum?Momentum is defined as the product of mass and velocity. It is expressed as
Momentum = mass × velocity
With the above formula, we can obtain the momentum of the bullet. Details below.
The following data were obtained from the question:
Mass of bullet = 35 g = 35 / 1000 = 0.035 KgVelocity = 126 Km/h = 126 / 3.6 = 35 m/sMomentum =?Momentum = mass × velocity
Momentum = 0.035 Kg × 35 m/s
Momentum = 1.225 Kg.m/s
From the calculation made above, we can conclude that the linear momentum of the bullet is 1.225 Kg.m/s
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The first P-wave of an earthquake travels 5600 kilometers from the epicenter and arrives at a seismic station at 10:05 a.m. At what time did this earthquake occur?
Ahhhhhh I have a Regent's test in 2 hours and I don't know how to solve this type of question! Any help would be appreciated.
Anyone know what the steps to do this are? I dont even need an answer, just how to get to it. Thank you!
The earthquake would occur 13 minutes before 10:05 a.m. which will be at 9.52 am.
The p-waves travel with a constant velocity of 7 km/s
The time can be calculated by using the formula
t = d / v
where
T1 = 10:05 a.m
d is the distance they take to travel from the epicenter
v is the speed of the p-waves
On average, the speed of p-waves is
v = 7 km/s
d = 5600 km (given)
Substituting the values in the formula;
t = d / v
t = 5600 ÷ 7
t = 800 seconds
Converting into minutes,
t = 800 ÷ 60
t = 13.3
≈ 13 mins
T1 - 13 mins = T2
10:05 - 13 mins = 9.52 am
It means the earthquake occurred prior 13 minutes, that is at 9.52 am.
Therefore, the earthquake occurred at 9.52 am.
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Find the Magnitude of the resultant vector (the actual
path of the boat).
The picture is a little blurry, so here are the stats:
Velocity of the boat is 0.75 m/s
Velocity of the river is 1.2 m/s
The magnitude of the resultant vector, representing the actual path of the boat, is approximately 1.42 m/s.
To find the magnitude of the resultant vector, we need to consider the boat's velocity and the velocity of the river. The boat's velocity is given as 0.75 m/s, and the river's velocity is given as 1.2 m/s.
Since the boat is moving in a river, we can think of the boat's velocity as a combination of two velocities: its own velocity and the velocity of the river. The resultant vector represents the actual path of the boat, considering both velocities.
To calculate the resultant vector, we can use vector addition. The magnitude of the resultant vector can be found by taking the square root of the sum of the squares of the boat's velocity and the river's velocity. Mathematically, we have:
Resultant magnitude = √(boat velocity^2 + river velocity^2)
Plugging in the given values, we have:
Resultant magnitude = √(0.75^2 + 1.2^2)
= √(0.5625 + 1.44)
= √2.0025
≈ 1.42 m/s
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What is energy?
Question 1 options:
force × distance
force
chemical change
the ability to do work
Answer:
The ability to do work
Explanation:
Energy can be defined as the ability to do work. We apply energy in basically everything we do in life, energy is needed to walk or move from one position to another, it is required to eat and do other basic things of life. The body system converts the food that is being consumed into energy, this energy can be switched from one form to another.
There are various forms of energy which include solar energy , wind energy, electrical energy, mechanical energy, kinetic energy, potential energy etc. This forms of energy can be converted from one form to anothe but cannot be destroyed.
Answer:
ability to work
Explanation:
How can a spinning ball have more lift than one that is not spinning?
Why does the direction of the spin matter?
Relate Bernoulli's principle to the sport of your choice.
The differential in air pressure on the ball's various sides allows a spinning ball to provide more lift than a non-spinning ball, in accordance with Bernoulli's principle.
According to Bernoulli's principle, the pressure of a fluid decreases as the fluid's velocity increases. A ball is pushed in the opposite direction by a force produced by lower pressure, possibly producing more lift.
The lift is given to the ball by the air because the right side air moves in the same direction of the motion of the ball while the lift side goes into the opposite direction that creates a difference in the air pressure and more lift is the result.
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Find the locations of the object when its velocity is one-third of the maximum speed. Treat the equilibrium position as zero, positions to the right as positive, and positions to the left as negative.
Answer:
let x = A sin ω t describes location of object at time t
V = A ω cos ω t velocity of object at time t
Vmax = A ω max speed occurs when ω t = 0 velocity / max velocity
V / Vmax = 1/3 = cos ω t
θ = ω t angle being considered
cos θ = 1/3
1/3 max speed occurs at cos θ = ±1/3
θ = ±70.5 deg
please help me out with this
The current flowing through the 1Ω resistor in the circuit is 0.66 A.
The emf of the cells, V = 1.1 V
Internal resistance of the cells, r = Ω
Resistance across the circuit, R = 1 Ω
According to Kirchhoff's current law, the total current flowing into and out of a junction in an electrical circuit is equal.
According to Kirchoff's current law,
(1.1 - V'/2) + (1.1 - V'/2) + (1.1 - V'/2) = V'/1
3/2(1.1 - V') = V'
3.3 - 3V' = 2V'
5V' = 3.3
Therefore, the terminal velocity of the battery is,
V' = 3.3/5
V' = 0.66 V
Therefore, according to Ohm's law, the current flowing through the 1Ω resistor is given by,
I = V'/R
I = 0.66/1
I = 0.66 A
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The input and output forces for four machines are shown in the table. Machine Forces Machine Input Force (N) Output Force (N) 1 5 50 2 10 50 3 25 50 4 50 50 Which machine would have the greatest mechanical advantage? Responses 1 1 2 2 3 3 4
Machine 1 has the greatest mechanical advantage among the given machines. To determine the machine with the greatest mechanical advantage, we need to calculate the mechanical advantage for each machine.
Machine 1: Mechanical Advantage = Output Force / Input Force = 50 N / 5 N = 10
Machine 2: Mechanical Advantage = Output Force / Input Force = 50 N / 10 N = 5
Machine 3: Mechanical Advantage = Output Force / Input Force = 50 N / 25 N = 2
Machine 4: Mechanical Advantage = Output Force / Input Force = 50 N / 50 N = 1
Comparing the mechanical advantages, we can see that Machine 1 has the highest mechanical advantage of 10. This means that Machine 1 can multiply the input force by 10 to produce the output force. It provides the greatest amplification of force among the four machines.
Machine 2 has a mechanical advantage of 5, Machine 3 has a mechanical advantage of 2, and Machine 4 has a mechanical advantage of 1. Therefore, Machine 1 has the greatest mechanical advantage among the given machines.
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m
An ostrich accelerates from rest until reaching a speed of 6.0 A graph of the ostrich's velocity over time
is shown below.
S
Velocity
()
6+
3+
Time (s)
3 6 9 12 15 18
What is the ostrich's average acceleration from 9.0 to 18 seconds?
O
Answer:
0 m/s2
Explanation:
khan
Dangers of physical in heat and
humidity include:
A)hypothermia
B)frostbite
C)muscle cramps
D)wind chill index
What do you understand by the term "Eigen function and Eigen value" in quantum mechanics. Give an example each.
In quantum mechanics, an eigenfunction is a function that satisfies a particular differential equation and is used to describe the behavior of a physical system. An eigenvalue is a scalar value that corresponds to an eigenfunction and represents the magnitude of a physical property of the system.
An example of an eigenfunction in quantum mechanics is the wavefunction, which is used to describe the probability distribution of a particle in a particular state. The wavefunction is an eigenfunction of the Schrödinger equation, which is a fundamental equation in quantum mechanics that describes the time evolution of a physical system.
An example of an eigenvalue in quantum mechanics is the energy of an atom in a particular state. The energy of an atom is an eigenvalue of the Hamiltonian operator, which is a mathematical operator that describes the energy of a physical system.
In general, eigenfunctions and eigenvalues play a central role in the analysis of quantum mechanical systems and are important tools for understanding the behavior of particles at the atomic and subatomic scales.
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An ice skater is moving in a circle at a constant speed. Which of the following best explains the forces acting on the ice skater.
Please give answer I’ll give brainiest
A. Ice skater is moving so the forces acting on her must be unbalanced
B.the ice skater has a constant speed so the forces acting on her must be unbalanced
C. The ice skater had a changing cellos the forces acting on her must be unbalanced
D.not enough information to answer the question
How have astronomers used models to explain galactic evolution through mergers and collisions? Use this model to explain how astronomers might test their understanding of the physical processes of the universe.
Answer:
Astronomers use computer models to simulate the process of galactic evolution through mergers and collisions. These models are based on our current understanding of the physical laws that govern the behavior of matter and energy in the universe. By running simulations of galactic mergers and collisions, astronomers can test their understanding of how these physical processes work in practice and how they contribute to the formation and evolution of galaxies.
One way that astronomers might test their understanding of the physical processes of the universe is by comparing the predictions of their models to observations of real galaxies. For example, if a model predicts that a particular type of galaxy should have a certain shape, size, or distribution of stars, astronomers can compare these predictions to observations of actual galaxies to see if they match up. If there is a discrepancy between the model's predictions and the observations, this can indicate that there are some physical processes that are not well understood or included in the model.
Another way that astronomers might test their understanding is by looking for patterns or trends in the properties of galaxies that are consistent with the predictions of their models. For example, if a model predicts that galaxies that have undergone a recent merger should have a particular distribution of gas and dust, astronomers can look for evidence of this pattern in observations of real galaxies. If they find that the predicted pattern is consistently observed in a large sample of galaxies, this can provide support for the model's predictions and the physical processes that it includes.
Overall, computer models of galactic evolution through mergers and collisions provide a powerful tool for astronomers to test their understanding of the physical processes of the universe. By comparing the predictions of their models to observations of real galaxies and looking for consistent patterns and trends, astronomers can refine their understanding of how galaxies form and evolve over time.
Which statement is true
Cells usually take in large food molecules
Cells can get energy by breaking down molecules from food
Cells use energy to help an organism grow and live
Breaking down molecules does not release energy
1. If the distance between the center of the fifth compression and the center of the ninth compression of a longitudinal wave is 4m, then the wavelength of this wave is
a. 9 m. b. 1.2 m. c. 1.5 m. d.)1 m.
The wavelength of this wave is 1 meter (option d).
To determine the wavelength of a longitudinal wave, we need to find the distance between two consecutive compressions or rarefactions. In this case, the distance between the center of the fifth compression and the center of the ninth compression is given as 4 meters. Since there are four compressions between the fifth and ninth compression, the total distance covered by these four compressions is 4 meters. Therefore, the average distance between consecutive compressions is 4 meters divided by 4, which is 1 meter. The wavelength of a longitudinal wave is the distance between two consecutive points with the same phase, which, in this case, is the distance between consecutive compressions. It is important to note that the number of compressions or rarefactions does not directly affect the wavelength. The wavelength is determined by the distance between consecutive points with the same phase. In this case, the given information allows us to calculate the average distance between consecutive compressions, giving us the wavelength of the wave. (option d).
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a dog runs back and forth between its two owners, who are walking toward one another. the dog starts running when the owners are 10 m apart. if the dog runs with a speed of 3 m/s and the owners each walk with a speed of 1.3 m/s how far has the dog traveled when the owners meet
Answer:
11.54 meters
Explanation:
The owners take 10m / (1.3 + 1.3 m/s) = 3.85 seconds to meet
The dog is running at constant speed of 3 m/s for these 3.85 seconds
3 m/s * 3.85 sec = 11.54 meters
1. A charge of 6.4 C passes through a cross-sectional area or conductor in 2s. How much charge will pass through a cross sectional area of the conductor in 1 min?
The amount of charge that will pass through the cross-sectional area of the conductor in 1 min is 192 C.
What is the amount of charge?
We can use the formula Q = I * t,
where;
Q is the amount of charge, I is the current, and t is the time.Given that a charge of 6.4 C passes through a cross-sectional area of the conductor in 2 s, we can find the current using the formula:
I = Q / t = 6.4 C / 2 s = 3.2 A
So, the current through the conductor is 3.2 A.
To find the amount of charge that will pass through the cross-sectional area of the conductor in 1 min (60 s), we can use the same formula:
Q = I * t = 3.2 A * 60 s = 192 C
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A bicyclist travels 30 km in 2 hours east. Calculate its velocity?
Answer:
See below
Explanation:
30 km / 2 hr = 15 km / hr eastward
1,000 J of energy are needed to melt 10 g of a solid substance that is already at its melting point. What is the heat of fusion of the substance?
1,000 J of energy are needed to melt 10 g of a solid substance that is already at its melting point , the heat of fusion of the substance is 548 joules .
What is heat of fusion ?Heat of fusion, also known as enthalpy of fusion or latent heat of fusion, is the amount of energy required to melt or freeze a substance under constant pressure conditions. When it comes to chemistry, "fusion" is basically synonymous with "melting." In the classroom, heat of fusion is typically used when a substance is at its melting or freezing point. In such instances, most people consider heat of fusion to be a constant.
Water, for example, has a heat of fusion of 334 J/g at its melting point of 0°C. At 0°C, one grams of liquid water requires 334 Joules of energy to completely freeze into ice. In addition, one grams of ice requires 334 Joules of energy to melt entirely.
q = m×∆Hf
q: Total change in heat energy (in Joules)
∆Hf: Heat of fusion of substance (in Joules per gram)
m: Mass of substance (in grams)
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Help ASAP). Describe the Net Force lab and explain what the lab demonstrated? Will Mark Brainliest. Working on it now can someone please help
Answer:
In the statement of Newton's first law, the unbalanced force refers to that force that does not become completely balanced (or canceled) by the other individual forces. If either all the vertical forces (up and down) do not cancel each other and/or all horizontal forces do not cancel each other, then an unbalanced force exists. The existence of an unbalanced force for a given situation can be quickly realized by looking at the free-body diagram for that situation. Free-body diagrams for three situations are shown below. Note that the actual magnitudes of the individual forces are indicated on the diagram.
In each of the above situations, there is an unbalanced force. It is commonly said that in each situation there is a net force acting upon the object. The net force is the vector sum of all the forces that act upon an object. That is to say, the net force is the sum of all the forces, taking into account the fact that a force is a vector and two forces of equal magnitude and opposite direction will cancel each other out. At this point, the rules for summing vectors (such as force vectors) will be kept relatively simple. Observe the following examples of summing two forces:
Observe in the diagram above that a downward vector will provide a partial or full cancellation of an upward vector. And a leftward vector will provide a partial or full cancellation of a rightward vector. The addition of force vectors can be done in the same manner in order to determine the net force (i.e., the vector sum of all the individual forces). Consider the three situations below in which the net force is determined by summing the individual force vectors that are acting upon the objects.
In modified PE football, the quarterback can only run with the ball if
A The quarterback has no open receivers
B Time runs out
C Another player on the offense touches the ball before the play starts
D it is 4th down
Answer:
its c i just did the test
Explanation:
the efficiency of combine double pulley is 60 how much load is lifted using 50n effort
The amount of load lifted by the pulley when the efficiency is 60% and effort is 50 N is determined as 30 N.
What is the amount of load lifted?The amount of load lifted by the pulley is calculated by applying the formula for efficiency of a machine as follows;
E = L / E x 100%
where;
L is the load overcome or output workE is the effort applied or the input workThe amount of load lifted by the pulley is calculated as;
60 = L / 50 x 100%
60 = 100L / 50
100L = 50 x 60
100 L = 3000
L = 3000 / 100
L = 30 N
Thus, the amount of load lifted by the pulley is 30 N.
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The purpose of the chiller is to
A. remove heat from the air.
B. cool conditioned air.
C. distribute the refrigerant.
D. cool warmed water.
The purpose of the chiller is to remove heat from the air and is therefore denoted as option A.
What is a Chiller?This is a type of device which is referred to as type of a cooling system that removes heat by circulating heat-absorbing a refrigerant through a series of mechanisms through which the heat is released.
The result of this process is that the heat in the air is removed as a result of the refrigerant being adequately circulated and then the environment becomes cooler and is therefore the reason why it was chosen as the correct choice.
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A particle changed q= 3,10x10^-6 C stays still on point P, a second particle with the same value q and a mass of 1,80x10^-2 kg is initially in repose at a distance of r1 = 9,00 cm from point P. This is second particle is released and repelled by the first. Determine the velocity in which this second particle finds itself at a distance r2 = 25,0 cm from point P.
note 1: from what i know i have to use the potential energy formula (U= mV^2/2), and possible calculate the electric force ? but from there i get lost
note 2: sorry if this isn't grammatically correct, i translated it from spanish
The velocity in which this second particle finds itself at a distance r2 = 25,0 cm from point P is 17.22 m/s.
What is the electric force between the two particles?The electric force between the two particles is calculated from Coulomb's law of electrostatic force.
F = kq₁q₂/r²
where;
k is Coulomb's constantq₁ is magnitude of first chargeq₂ is magnitude of second charger is the distance between the two chargesF = (9 x 10⁹ x 3.10 x 10⁻⁶ x 3.10 x 10⁻⁶) / (0.09 m)²
F = 10.68 N
The velocity in which this second particle finds itself at a distance r2 = 25,0 cm from point P is calculated by applying the principle of conservation of energy.
W = ΔK.E
where;
W is work doneΔK.E is kinetic energy of the particleFr = ¹/₂mv²
2Fr = mv²
v² = 2Fr/m
v = √(2Fr/m)
v = √(2 x 10.68 x 0.25 / 1.8 x 10⁻²)
v = 17.22 m/s
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Question #10. A rock is white in color, when viewed in sunlight.. In a windowless room, red light is shined on the rock. What color will it appear to your eyes?
We will have the following:
Since it is a white rock, then when in a windowless room with just red light the color that will appear to our eyes is red. Since is the only color to reflect.
A stone is thrown from a point A at the top of a building of height H = 14 m with an initial downward velocity v - -2m/s. What is the time needed for this stone to reach a point B at a height h = 4 m above the ground? Neglect the effect of air resistance, and use g = 10 m/s
Given
Total height of the building, H=14 m
The initial velocity is v=-2 m/s
The point B is at height, h=4 m.
To find
The time need by the stone to reach point B.
Explanation
Using the equation of kinematics,
\(y=ut+\frac{1}{2}gt^2\)where y is the distance covered.
t is the time taken
Thus,
\(\begin{gathered} H-h=vt+\frac{1}{2}gt^2 \\ \Rightarrow14-4=2t+\frac{1}{2}\times10\times t^2 \\ \Rightarrow10=5t^2+2t \\ \Rightarrow5t^2+2t-10=0 \\ \Rightarrow t=\frac{-2\pm\sqrt{4+200}}{10} \\ \Rightarrow t=1.28\text{ s \lparen considering only the positive term\rparen} \end{gathered}\)Conclusion
The time is 1.28 s