When a particle is projected at 36 m/s from ground,
a) Time for which it is above a height of 63 m is 2.8s
b) The speed for which it has at this height of 63 m is 7.82 m/s
c) total time of flight is 7.34s.
What is Velocity & acceleration ?Velocity is "rate of change of displacement with respect to time".
i.e. v= dx/dt
it is also defined as displacement over time. i.e. v=Displacement/Time.
Velocity shows how much distance can be covered in unit time. It's SI unit m/s.
Acceleration is rate of change of velocity with respect to time.
i.e. a = dv/dt
if an object changes its velocity in short time, we can say that it has grater acceleration.
a= dv/dt =Δv/Δt
Given,
Initial velocity u = 36 m/s
Height of the particle s = 63m
acceleration due to gravity g=9.8 m/s²
a) According to equation of kinematics,
s=ut+1/2gt²
putting all the values in equation,
63=36t+(1/2)(-9.8)t²
multiplying by 2
126=72t-9.8t²
9.8t² -72t +126 = 0
on solving this quadratic equation, we get
t=4.4s or t=2.8s
(Correct option is t=2.8s)
Hence time to attain 63 m of height is 2.8s
b)According to equation of kinematics,
v²=u²+2as
v² = 36²+2(-9.8)×63 (negative sigh is for velocity and acceleration are oppositely directed)
v² = 61.2
v= 7.82 m/s
Hence Speed at this height is 7.82 m/s
c) Total time of the flight is
at max position of height, final velocity v=0
v= u+at
0=36+(-9.8)t
t= 36/9.8
t = 3.67s .......this is time taken by particle to complete journey from bottom to top,
now it will take same time for particle to come from bottom to top.`
therefore total time taken by particle to go from bottom to top then return back is 2×3.67s
t= 7.34s
Hence total time taken by flight is 7.34s
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PLEASE HELP EXPERTS
Developing camaraderie, paying attention, and taking part in training are all ways to:
A. Professionally Communication Online
B. Problem solve
C. Avoid making work mistakes
D. Important
E. Vital Functions
E. Vital Functions of a Team. Developing camaraderie is an important part of creating a team atmosphere, as it helps team members to learn to trust and rely on each other.
What is atmosphere ?Atmosphere is the layer of gases that surrounds the Earth. It is composed of roughly 78% nitrogen, 21% oxygen, and 1% other gases, such as argon, carbon dioxide and water vapor. The atmosphere protects the Earth from harmful ultraviolet radiation from the sun, shelters us from extreme temperatures, and creates the air pressure that allows us to breathe. The air we breathe is a mixture of gases, and the atmosphere also contains dust, smoke and other particles.
Paying attention during training helps to ensure that team members have all the necessary information to be able to perform their duties, while taking part in team activities and training helps to strengthen team bonds and create a sense of unity.
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Starting from rest, a 32.2 kg child rides a 9.00 kg sled down a frictionless ski slope. At the bottom of the hill, her speed is 6.8 m/s. If the slope makes an angle of 16.9° with respect to the horizontal, how far along the hill did she slide on her sled?
To solve this problem, we can use conservation of energy:
Initial mechanical energy (at the top of the hill) = final mechanical energy (at the bottom of the hill)
Initial mechanical energy = mgh, where m is the total mass of the child and sled, g is the acceleration due to gravity (9.8 m/s^2), and h is the vertical height of the hill. Since the hill makes an angle of 16.9° with respect to the horizontal, we can use trigonometry to find the height:
h = (length of slope) * sin(16.9°)
We don't know the length of the slope, but we can solve for it by using the final speed of the child and sled:
Final mechanical energy = (1/2)mv^2, where v is the final speed of the child and sled.
Setting these equal, we get:
mgh = (1/2)mv^2
Substituting for h and solving for the length of the slope:
(length of slope) = v^2 / (2g*sin(16.9°))
Plugging in the given values:
(length of slope) = (6.8 m/s)^2 / (29.8 m/s^2sin(16.9°)) ≈ 12.5 meters
Therefore, the child and sled slide about 12.5 meters along the slope.
2. Given the displacement vectors A = 3i-1j+4k, B = 2i+ 3j - 0k. Find the magnitudes of the vectors a) A + 1B b) 2A - B
The magnitudes of the vectors (A+1B) and (2A - B) would be 6.71 and 10.25 respectively
Vector operationa) The vector A + B can be found by adding the corresponding components of A and B:
A + B = (3i - 1j + 4k) + (2i + 3j - 0k) = 5i + 2j + 4k
The magnitude of A + B is:
|A + B| = sqrt((5)^2 + (2)^2 + (4)^2) = sqrt(45) ≈ 6.71
b) The vector 2A - B can be found by multiplying the components of A and B by the appropriate scalar values and then subtracting:
2A - B = 2(3i - 1j + 4k) - (2i + 3j - 0k) = 6i - 2j + 8k - 2i - 3j = 4i - 5j + 8k
The magnitude of 2A - B is:
|2A - B| = sqrt((4)^2 + (-5)^2 + (8)^2) = sqrt(105) ≈ 10.25
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How is the kinetic energy of the measured velocity compared to the predicted kinetic energy based on the height of the
release? Explain any possible reason for the discrepancy.
The object's kinetic energy, in contrast to potential energy, is relative to other fixed and moving things that are present inside its immediate vicinity.For instance, if the item is positioned at a higher height, its kinetic energy will be higher.
Why then does kinetic energy drop down as height increases?As height is reduced, potential energy is reduced as well.If height lowers, the kinetic energy for a freefall similarly reduces.That is as a result of the shorter distance to be traveled.
How do height and energy relate to one another?A doubling in height will lead to a doubling in gravitational potential energy since an object's gravitational potential energy is directly proportionate to its height above the zero point.The potential energy of gravity will triple with a tripling of height.
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Please help (50 points and Brainly)
The work done in raising an object is equal to the force applied to the object multiplied by the distance it is moved.
What is object ?Objects in programming are entities that contain data and can be manipulated by code. They are commonly used to represent real-world things, such as a customer or an employee, or even abstract concepts such as a bank account. Objects are made up of properties, which are the data associated with the object, and methods, which are functions that objects can perform. Objects interact with one another through messages, which are sent from one object to another, allowing them to work together.
Therefore, we can calculate the distance the apple is lifted using the formula:
Work = Force × Distance
2.0 J = (0.180 kg)(9.8 m/s2) × d
d = 2.0 J / (0.180 kg)(9.8 m/s2)
d = 12.2 m
The apple is lifted 12.2 meters.
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Which of the following
P = E/t, where P is for power, E is for energy, and t is for time in seconds, denotes this relationship. Power is defined as the amount of energy consumed per unit of time according to this formula. Choice D
Describe energy in plain terms.Energy is the capacity to perform work, according to scientists. Because of the ability to transform energy from one type of energy to another and use it to accomplish tasks, modern civilisation is feasible.
What elements comprise energy?Energy is a term that denotes a property of matter & non-matter fields; energy is not a substance in and of itself. For instance, it's argued that kinetic energy exists when a substance moves. Potential energy comes in many different forms as well.
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Third Law of Motion
For every action, there is an equal and opposite reaction .
I hate physics ! Hope you guys can help !
Answer: NEWTONS FIRST LAW
One's body moves to the side when a car makes a sharp turn.
Tightening of seat belts in a car when it stops quickly.
A ball rolling down a hill will continue to roll unless friction or another force stops it.
If pulled quickly, a tablecloth can be removed from underneath dishes.
NEWTONS SECOND LAW
1· Try to move an object.
2· Pushing a car and a truck.
3· Racing Cars.
4· Rocket launch.
5· Kick the ball.
6· Car crash.
7· Two people walking.
8· Object thrown from a height
Newton's Second Law of Motion says that acceleration (gaining speed) happens when a force acts on a mass (object). Riding your bicycle is a good example of this law of motion at work. Your bicycle is the mass. Your leg muscles pushing on the pedals of your bicycle is the force.
NEWTONS THIRD LAW
Examples
The recoil of a Gun. ...
Swimming. ...
Pushing the Wall. ...
Diving off a Raft. ...
Space Shuttle. ...
Throwing a Ball. ...
Walking. ...
Hammering a Nail.
More items...
Common examples of newton's third law of motion are: A horse pulls a cart, a person walks on the ground, a hammer pushes a nail, and magnets attract paper clips. In all these examples a force is exerted on one object and that force is exerted by another object.
If a machine is perfect, the mechanical advantage will be ....... the velocity ratio.
greater than
less than
equal to
none of these
Answer:
Equal to
Explanation:
work output is equal to the work input, so the efficiency is equal to 1 ( or 100% ) and the mechanical advantage is numerically equal to the velocity ratio. So, M.A. = V.R.
What is the acceleration if the velocity is 38 km/hr and the time is 2.5 hrs?
The acceleration of the moving vehicle when velocity and time is given would be = 15.2 km/hr²
What is acceleration?Acceleration is defined as the quantity that shows the change on velocity of a moving object with respect to change in time.
That is;
acceleration = ∆velocity/∆time.
Velocity is defined as the change in the distance of a moving object with respect to time.
The velocity of the moving vehicle = 38km/hr
The time given = 2.5 hrs
Acceleration = velocity/time
= 38/2.5
= 15.2 km/hr²
Therefore, the acceleration of the vehicle when velocity and time is given = 15.2 km/hr².
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If a town installs new power lines in the middle of summer, what factor needs to be accommodated in their set up?
When a town puts in new power lines during the height of summer, it needs to be able to handle the increased electrical load on the power grid that will probably come from more people using air conditioners.
Summer is the hottest season in many parts of the world, so people rely a lot on air conditioning to keep their homes and businesses cool. As a result, the summer months typically see the greatest demand for electricity.When new power lines are installed, what upgrades are required?The power grid needs to be able to handle the increased demand for electricity that will result from the use of air conditioning when new power lines are installed. In order to guarantee that there is sufficient capacity to meet the increased demand, this may necessitate improvements to the existing infrastructure, which may include transformers, distribution lines, and substations.
In addition, it may be necessary to coordinate the installation of new power lines with the local utility company to avoid disrupting the existing power supply to homes and businesses. This may necessitate temporary power outages or other measures to guarantee that the installation goes off without a hitch and does not pose any safety risks.
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A force, F, acts horizontally on a stationary mass, m, on a horizontal, frictionless surface. After a displacement of one metre, the mass has a velocity v. If a force 2F acts for the same displacement on a mass 1/2m, initially at rest on the same surface, what velocity will the second mass have?
The second mass will have a velocity of v² = 4√F of the force, F. Since the displacement and the force are the same in both cases
What is frictional force?Frictional force is a force that opposes motion between two surfaces in contact. When two surfaces are in contact, there are microscopic irregularities that prevent them from sliding over each other easily. As a result, a force is required to overcome this resistance and move one surface over the other.
The frictional force between two surfaces depends on several factors, including the type of surfaces in contact, the force pressing the surfaces together (normal force), and the presence or absence of lubrication.
According to the work-energy principle, the work done by a force on an object is equal to the change in the object's kinetic energy. This principle can be used to solve the problem.
For the first case, the work done by the force F is:
W = Fd
where d is the displacement of the mass. This work is equal to the change in kinetic energy of the mass:
W = ΔK
where ΔK = (1/2)mv² - 0 is the change in kinetic energy, since the mass starts from rest.
Combining these equations, we get:
Fd = (1/2)mv²
For the second case, the work done by the force 2F is:
W = 2Fd
This work is equal to the change in kinetic energy of the mass:
W = ΔK
where ΔK = (1/2)(1/2)m v₂² - 0 is the change in kinetic energy, since the mass starts from rest.
Combining these equations, we get:
2Fd = (1/4)mv₂²
Solving for v², we get:
v² = √(8Fd/m)
Since the displacement and the force are the same in both cases, we can substitute the first equation into the expression for v²:
v² = √(8F(1 m)/(1/2m))
v² = √(16F)
v² = 4√F
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Please help (50 points and Brainly)
The final kinetic energy of the student is 352 J. We can use the formula for kinetic energy, $KE=\frac{1}{2}mv^2$, to solve for the final velocity, $v$,
What is kinetic energy ?Kinetic energy is the energy of motion. It is the energy that an object has due to its motion. It is one of the forms of energy that exist in nature. Kinetic energy is related to the mass of an object and its velocity. The greater the mass of an object, or the faster its velocity, the more kinetic energy the object possesses. Kinetic energy can be converted into other forms of energy such as heat or electricity, and can also be transferred from one object to another.
$352 = \frac{1}{2}mv^2$
$v = \sqrt{\frac{352}{m}}$
where $m$ is the mass of the student.
Now, we can use the equation for work, $W=Fd$, to calculate the distance the student must be pushed to reach the final velocity:
$W = Fd = mv^2$
$d = \frac{mv^2}{F} = \frac{m\sqrt{\frac{352}{m}}}{45} = \frac{\sqrt{352m}}{45}$
Therefore, the student must be pushed a distance of $\frac{\sqrt{352m}}{45}$ to reach a final kinetic energy of 352 J.
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Block A (mass = 5 kg) with an initial velocity of 10 m/s right, collides with block B (mass = 10 kg) which is at rest. The final velocity of B is 6 m/s right. What is the final velocity (magnitude and direction) of A? The surface is frictionless.
The final velocity of block A is -2 m/s to the left ( in the opposite direction of its initial velocity).
What is velocity?Quantity that designates how fast and in what direction a point is moving is known as velocity.
As we know, m_A * v_Ai + m_B * v_Bi = m_A * v_Af + m_B * v_Bf
m_A and m_B are the masses of blocks A and B, v_Ai and v_Bi are their initial velocities, and v_Af and v_Bf are their final velocities.
5 kg * 10 m/s + 10 kg * 0 m/s = 5 kg * v_Af + 10 kg * 6 m/s
50 kgm/s = 5 kg * v_Af + 60 kgm/s
-10 kg*m/s = 5 kg * v_Af
So, v_Af = -2 m/s
Therefore, the final velocity of block A is -2 m/s to the left (i.e., in the opposite direction of its initial velocity).
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What is the acceleration on a body that approached the earth and comes within 6
earth radii of the earth’s surface?
The acceleration on a body that approached the earth and comes within 6 earth radii of the earth’s surface is 0.2 m/s².
How can we calculate the acceleration of the body?The acceleration of the body can be calculated using the equation-
g = g0 R/(R + H)².
In the question, we have, h = 6R
g = 9.8 x R/(R + 6R)²
By putting in the values and calculating, we get,
g = 0.2 m/s².
What causes a body to accelerate when the earth attracts it?Where g' = Gravitational Acceleration at Height, R = Earth's Radius, and g = Gravitational Acceleration at Earth's Surface. As a result, at a distance of 2R from the earth's surface, the acceleration of a body caused by the earth's attraction is equal to g/9.
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A pulley system is used to lift a 2000 N grand piano a distance of 3 meters. The mover applies 300 N of force in the process. a) Calculate the mechanical advantage of the pulley system. b) How much work does the machine do? c) If the mover pulls 27 meters of rope to lift the piano, how much work does he do? d) What is the efficiency of the pulley system?
a) 7 b) 6000 J c) 8000 J d) 75%
a) 9 b) 3000 J c) 6000 J d) 55%
a) 4 b) 3000 J c) 9000 J d) 85%
a) 14 b) 8000 J c) 6000 J d) 75%
very important!!!
A drilling rig performs 5.15∗105 J of work at an average power output of 3940 W. How long does it take the drill to perform this work?
540 s
916 s
244 s
131 s
Answer:131s
Explanation:
time = 5.15*10^5 J / 3940
In which of these situations would light slow down?
a.) from glass to air
b.) from ice to water
c.) from plastic to air
d.) from a vacuum to air
The situation in which light slow down is from a vacuum to air which is therefore denoted as option D.
What is a Vacuum?This is referred to as the space in which there is no matter or in which the pressure is so low that any particles in the space do not affect any processes.
When light travels through a medium other than vacuum, it will be slowed down. For instance, when light propagates through water or air, it will do so at a slower speed because the speed of light is faster in a vacuum than in any other medium and would slow down going from a vacuum to air.
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25 Point Emergency!!! Absurd answers will cause you're answer, and account, to be reported.
On a certain planet, a 4950 kg rock weighs 22,030 N. If this planet has a radius of 4200 km, what is the mass of the planet?
1.18∗10^24 kg
4.51∗10^24 kg
1.92∗10^25 kg
3.06∗10^25 kg
Answer:
F = G M1 M2 / R^2 attraction between 2 masses
M1 = F R^2 / (G M2)
M1 = 2.20E4 * (4.2E6)^2 / (6.67E-11 * 4.95E3) kg
M1 = 2.2 * 4.2^2 / (6.67 * 4.95) E24
M1 = 1.18E24 kg
which of the following is not a type of energy?
Answer:
Neutronic is not a defined type of energy.
A thin rod with length 4.5 m is sitting with one end at the origin. The rod has a non-uniform density that has a quadratic dependence. You know the density at three points. The density of the rod is 3.0 kg/m at the origin, 11.0 kg/m at the other end of the rod, and 3.0 kg/m halfway in between.
How far from the origin is the center of mass of the rod located?
The density of the rod is 3.0 kg/m at the origin,then the center of mass of the rod is located 2.15 m from the origin.
What is center of mass?The center of mass is the point in an object or system of objects where the mass of the object or system can be considered to be concentrated. In other words, it is the point in which an object or system can be balanced and behaves as if all the mass is concentrated at that point.
Evaluating :To find the center of mass of the rod, we need to integrate the product of the density and position of each infinitesimal element of the rod, divided by the total mass of the rod.
We can express the position of each element as x, where x=0 at the origin and x=4.5 m at the other end of the rod.
Let's start by finding the total mass of the rod. We can divide the rod into two parts: one from the origin to the midpoint, and the other from the midpoint to the other end. The mass of each part can be found by integrating the density over its length:
m₁ = ∫(0 to 2.25) 3x² dx = 15.19 kg
m₂ = ∫(2.25 to 4.5) (22.5x - 45.375) dx
= 95.63 kg
The total mass of the rod is then derived as follows:
m = m₁ + m₂ = 110.82 kg
We can now evaluate the location of the centre of mass. We can express the position of the center of mass as xcm, where x=0 at the origin and x=4.5 m at the other end of the rod.
We can use the formula:
xcm = (1/m) ∫(0 to 4.5) ρ(x) x dx
where (x) represents the density at position x.
We can express the density as a quadratic function of x:
ρ(x) = ax² + bx + c
Using the given values of density at the origin, midpoint, and other end, we can solve for the coefficients a, b, and c:
c = 3
a + b + c = 11/4.5
= 2.44
4a + 2b + c = 3
Solving these equations gives:
a = -1.96 kg/m³
b = 7.33 kg/m²
Now we can plug in the expression for ρ(x) and evaluate the integral:
xcm = (1/m) ∫(0 to 4.5) (-1.96x⁴ + 7.33x³ + 3x) dx
Evaluating this integral gives:
xcm = 2.15 m
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How can a hockey puck explain the transfer of kinetic energy? **Select all that apply.**
A. Kinetic energy transfers through air when materials are close.
B. Kinetic energy is lost when it transfers between materials.
C. Energy transfers from materials through touch.
D. Kinetic energy can move from one item to another.
A 0.300 kg mass is attached o a 26.6 N/m spring. It is pulled 0.120 m and released. How much Potential Energy does it have when it is 0.0600 m from equilibrium? ( Unit - J) (It's not 0.144 J)
The potential energy of the mass is 0.0452 J when it is at a distance of
0.0600 m from equilibrium.
How to calculate potential energy?
The potential energy stored in a spring when it is stretched or compressed by a displacement x is given by:
[tex]$PE = \frac{1}{2}kx^2$[/tex]
where k is the spring constant.
In this problem, the spring constant is given as 26.6 N/m, and the displacement of the mass from equilibrium is
[tex](0.120 m - 0.0600 m) = 0.0600 m.[/tex]
Therefore, the potential energy stored in the spring when the mass is at a distance of 0.0600 m from equilibrium is:
[tex]$PE = \frac{1}{2}kx^2 = \frac{1}{2}(26.6 N/m)(0.0600 m)^2 = 0.0452 J$[/tex]
So the potential energy of the mass is 0.0452 J when it is at a distance of 0.0600 m from equilibrium.
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Answer: 0.0479
Explanation: This answer works for Acellus! :D
hope this helps!
Remember that a measured value agrees with an established value if the established value is within a range of ±2Δx of the measured mean, where Δx is the standard uncertainty.
The table provides a range of modulus values for each material. Therefore, we cannot exclude a material as a possibility if the range in the table and the 95% confidence interval overlap.
Based on this, which of the materials shown above might the cylinder be? Select all that apply. (1 GPa = 1,000,000,000 Pa, and 1 Pa = 1 N/m2)
Butyl rubber is the measured value agrees with an established value if the established value is within a range of ±2Δx of the measured mean.
What is temperature ?
The movement of these particles likewise increases with rising temperature. A thermometer or a calorimeter are used to measure temperature.
What is reaction ?
The transformation of one or more reactants into one or more new products is referred to as a chemical reaction. Substances are made of chemical constituents or compounds. The transformation of one or more reactants into one or more new products is referred to as a chemical reaction. Substances are made of chemical constituents or compounds.
Therefore, Butyl rubber is the measured value agrees with an established value if the established value is within a range of ±2Δx of the measured mean.
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A car whose weight Fw is on an incline that makes an angle theta with the horizontal.How large a perpendicular force does the incline exert on the car
The perpendicular force exerted by the incline on the car is Fw cosθ.
What is normal reaction force ?Normal reaction force is defined as a contact force that is exerted by the surface on an object which is in contact with it. It prevents the object from passing through the surface.
Here,
Weight of the car is Fw
The incline makes an angle θ with the horizontal.
From the figure,
The perpendicular force exerted by the incline, N = Fw cosθ
Hence,
The perpendicular force exerted by the incline on the car is Fw cosθ.
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Which of the following cannot used to describe a wave?
a) Frequency
b) Height
c) Speed
d) Wavelength
Answer:
speed
Explanation:
speed
Kelly lifts a 4500-newton barbell at a height of 7 meters. What are the joules of work being put out?
Pls help and fast <3
Answer:
31,500 joules
Explanation:
Work = force * distance * cos(theta)
Force = 4500N (weight of the barbell)
Distance = 7m (the height lifted)
Theta = 0 (cosine of 0 degrees is 1, since the force and distance are in the same direction)
So, Work = 4500 N * 7m * cos(0)
Work = 31,500 joules
Assume the blue is a string and the orange is a meterstick. At the 50.1 cm mark, is there a pivot? Yes or No. Explain why
Resistors of 20 ohms, 20 ohms, and 30 ohms are connected in parallel. What resistance must be added in series with the combination to obtain a total resistance of 10 ohms. If the complete circuit expends 0.36 kW, find the total current flowing.
Answer:
Given:
R1 = 20 ohms
R2 = 20 ohms
R3 = 30 ohms
Total resistance = 10 ohms
Power = 0.36 kW
1/Req = 1/20 + 1/20 + 1/30
1/Req=2/15
Req 15/2
Req = 7.5 ohms
Hence, 10 - 7.5 = 2.5 ohms
PIR, hence 0.36 x 103
= I²(10)
I = √360/10 = √36 = 6 A
Approximately how quickly does sound cover 1 kilometre?
a) Instantly
b) 1 second
c) 2 seconds
d) 3 seconds
Answer:
3 second is the answer of your question
4. Determine the angle between the force F = (2i+ 5j) N and the displacement 5 = (-i+ 7) m. The work done in applying the force over the displacement is 33 J. A. 17.4° B. 21.6° C. 29.9° D. 32.7° E. 39.8°
Explanation:
The work done by a force F over a displacement d is given by the dot product of the force and the displacement:
W = F · d
where · denotes the dot product.
We are given that the work done is 33 J, so
F · d = 33 J
We can find the dot product by taking the sum of the products of the corresponding components:
F · d = (2i + 5j) · (-i + 7j) = 2(-1) + 5(7) = 33
Now, we can find the magnitude of the force and displacement vectors:
|F| = √(2² + 5²) = √29
|d| = √((-1)² + 7²) = √50
The angle between the force and displacement vectors can be found using the dot product:
F · d = |F| |d| cos θ
cos θ = (F · d) / (|F| |d|)
cos θ = 33 / (√29 √50)
cos θ ≈ 0.603
θ ≈ 53.2°
However, we are looking for the angle between the force and the displacement, which is the supplement of θ, so:
angle = 180° - 53.2° ≈ 126.8°
None of the answer choices match this result, so we must have made a mistake.
Let's check our work. We made an error in the calculation of the cosine of θ. It should be:
cos θ = (F · d) / (|F| |d|)
cos θ = 33 / (√29 √50)
cos θ ≈ 0.433
θ ≈ 64.2°
The angle between the force and displacement vectors is approximately 64.2°.
Now we can check the answer choices:
A. 17.4° - Too small
B. 21.6° - Too small
C. 29.9° - Too small
D. 32.7° - Too small
E. 39.8° - Too small
None of the answer choices match the calculated angle of 64.2°. Therefore, the correct answer is not among the choices given.