Answer:
a) t = 14.2 s , v = -92 m / s , b) v = - 59.16 m / s , t = 0.916 s
c) t = 7.75 s , x = 387.5 m
d) t = 10.64 s , x = 463.9 m , v = 92.2 m / s
Explanation:
This is an exercise in kinematics, suppose we take the upward direction as positive
a) is thrown up vertically.
Let's use the equation
y = y₀ + v₀ t - ½ g t²
When reaching the ground y = 0, the initial height is y₀ = 300 m and the initial velocity is v₀ = + 50m / s, to simplify we use g = 10 m /s² as the value of the acceleration of gravity, for a more exact calculation we can must use 9.80 m /s²
0 = y₀ + v₀t - ½ g t²
½ 10 t² - 50 t - 300 = 0
Let's solve the quadratic equation
t² - 10 t - 60 = 0
t = [10 ±√ (10² + 4 60)] / 2
t = [10 ± 18.4] / 2
t₁ = 14.2 s
t₂ = -4.2 s
since time must be a positive quantity, the correctors result t = 14.2 s
the speed at this point is
v = v₀ - g t
v = 50 - 10 14.2
v = -92 m / s
the sign indicates that the body is going down
b) in this case the initial velocity is vo = -50 m / s
let's calculate the velocity on the ground
v² = v₀² - 2g (y-y₀)
v² = 50 2 - 2 10 ((0- 300)
v² = 3500
v = + - 59.16 m / s
as the body is going down the correct sign is the negative
v = - 59.16 m / s
the time it takes to arrive is
v = v₀ - g t
t = (v₀ - v) / g
t = (-50 + 59.16) / 10
t = 0.916 s
c) the velocity is horizontal (vox = 50 m / s), this implies that the vertical velocity is zero voy = 0
y = y₀ + v₀ t - ½ g t²
0 = 300 + 0 - ½ 10 t²
t = √ (2 300/10)
t = 7.75 s
the horizontal displacement at this time is
x = v₀ₓ t
x = 50 7.75
x = 387.5 m
d) as it is thrown with an angle let's find each component of the velocities
v₀ₓ = v₀ cos 30
[tex]v_{oy}[/tex] = v₀ sin 30
v₀ₓ = 50 cos 30 = 43.3 m / s
v_{oy} = 50 sin 30 = 25 m / s
we look for the time of descent
y = y₀ + v_{oy} t - ½ g t²
0 = y₀ + v_{oy} t - ½ g t²
0 = 300 + 25 t - ½ 10 t²
t² - 5t - 60 = 0
we solve the second degree equation
t = [5 ±√ (5² + 4 60)] / 2
t = [5 ± 16.28] / 2
t₁ = 10.64 s
t₂ = -5.64 s
since the time must be positive the result is t = 10.64 s
the range on the x axis is
x = v₀ₓ t
x = 43.6 10.64
x = 463.9 m
the ground speed is
v_{y} = [tex]v_{oy}[/tex] - g t
v_{y} = 25 - 10 10.64
v_{y} = -81.4 m / s
speed is
v = √ (v₀ₓ² + v_{y}²)
v = √ (43.3² + 81.4²)
v = 92.2 m / s
State the career function of electrical engineering
Answer:
Explanation:
Electrical engineers design, develop, and test electrical devices and equipment, including communications systems, power generators, motors and navigation systems, and electrical systems for automobiles and aircraft. They also oversee the manufacture of these devices, systems, and equipment.
Answer:
Electrical engineering duties are to design and conduct research programs; applying knowledge of electricity and materials.
Help plz will give brainliest
Answer:
The forces acting on the root beer is the ice cream. This means that the 'air' in the ice cream keeps it at the top of the root beer enabling it to float right at the top.
a 77 N net force is applied to a box which slides horizontally across a floor for 6.7 m. What amount of work is done on the box by the net force ?
please help me very urgent :((
What is the net force (including direction and magnitude) acting on the object on the above left?
What is the net force (including direction and magnitude) acting on the object on the above right?
Answer:
-150 N
Explanation:
(Newton's second law) F=ma
Sum of forces in Y direction= (+200 N)+(-200 N)= 0...
forces cancel, object does not accelerate up/down
Sum of forces in X direction= (+65 N)+(-65 N)+(-150 N)
= -150 N
notice that the +/- 65 components cancel, leaving a net force of 150 N in the LEFTwards direction (which is typically defined as negative)
Overall, the net force is -150 N
i need to get magnitude of Ax and Ay, Bx and By. total resultant and direction of resultant
Now
[tex]\\ \tt\longrightarrow R=\sqrt{A^2+B^2+2ABcos\theta}[/tex]
[tex]\\ \tt\longrightarrow R=\sqrt{92^2+34^2+2(92)(34)cos135}[/tex]
[tex]\\ \tt\longrightarrow R=\sqrt{8464+1156+6256(-0.7)}[/tex]
[tex]\\ \tt\longrightarrow R=\sqrt{9620+4379}[/tex]
[tex]\\ \tt\longrightarrow R=\sqrt{13999}[/tex]
[tex]\\ \tt\longrightarrow R=118.3N[/tex]
La motocicleta que tiene el récord mundial de aceleración es una motocicleta eléctrica, llamada "Killacycle" la cual permite pasar de 0 Km/h a 100 km/h en tan solo 1.5 s ¿Cuál es la aceleración media de esta motocicleta?
Answer:
[tex]a=18.51\ m/s^2[/tex]
Explanation:
Given that,
Initial speed, u = 0 km/h
Final speed, v = 100 km/h = 27.77 m/s
Time, t = 1.5 s
We need to find the average acceleration of this motorcycle. It is equal to the rate of change of velocity and it is given by :
[tex]a=\dfrac{v-u}{t}\\\\a=\dfrac{v}{t}\\\\a=\dfrac{27.77\ m}{1.5\ s}\\\\a=18.51\ m/s^2[/tex]
So, the acceleration of the motorcycle is [tex]18.51\ m/s^2[/tex].
Which one of the following choices was not a stage in the formation of Earth's atmosphere?
A. A super-dense atmosphere composed mostly of methane.
B. A volatile atmosphere composed of carbon dioxide and water vapor.
C. An oxygenated atmosphere with nitrogen and free oxygen.
D. A primordial atmosphere composed of hydrogen and helium.
Answer:
A
Explanation:
cause I'm big brain :)
PLEASE HELP IF YOU KNOW THE ANSWER QUICK PLEASE!!!
Answer:
d
Explanation:
In which of the two following cases would you recommend winnowing ?
Case 1 : when lighter part of the mixture is useful and the husk is unwanted
Case 2 : when lighter part of the mixture is unwanted and the husk is useful
[tex]{\green{\underline{\textsf{\textbf{Case 2 :When lighter part of a mixture is unwanted and the husk is useful. }}}}}[/tex]
[tex]{\green{\underline{\textsf{\textbf{Explanation : }}}}}[/tex]
As we know that, Winnowing is used when the lighter particles is required to remove. Hence, in Case 2 the lighter part is removed and the remaining is needed.
A civil engineer must design a wheelchair-accessible ramp next to a set of steps leading up to a building. The height from the ground to the top of the stairs is 2 ft. Based on ADA codes, the slope must be 1:12 or less. Slope is equal to the rise of the ramp divided by the run of the ramp.
A) Using the ADA code, what is the allowable minimum length of the ramp base?
B) Using the known height and calculated base length, what is the length of the slope of the ramp?
C) What is the ideal mechanical advantage of the ramp?D) If a person and wheelchair have a combined weight of 165 lb, how much ideal effort force is required to travel up the ramp?
Answer:
A) B = 24 ft
B) H = 24.08 ft
C) M.A = 12.04
D) P = 13.7 lb
Explanation:
A)
Minimum allowable length of base of ramp can be found as follows:
Slope = H/B
where,
Slope = 1/12
H = Height of Ramp = 2 ft
B = Length of Base of Ramp = ?
Therefore,
1/12 = 2 ft/B
B = 2 ft * 12
B = 24 ft
B)
The length of the slope of ramp can be found by using pythagora's theorem:
L = √H² + B²
where,
H = Perpendicular = height = 2 ft
B = Base = Length of Base of Ramp = 24 ft
L = Hypotenuse = Length of Slope of Ramp = ?
Therefore,
H = √[(2 ft)² + (24 ft)²]
H = 24.08 ft
D)
The mechanical advantage of an inclined plane is given by the following formula:
M.A = L/H
M.A = 24.08 ft/2 ft
M.A = 12.04
D)
Another general formula for Mechanical Advantage is:
M.A = W/P
where,
W = Ideal Load = 165 lb
P = Ideal Effort Force = ?
Therefore,
12.04 = 165 lb/P
P = 165 lb/12.04
P = 13.7 lb
In a drag race, a car takes off from rest and covers 375 meters in 5 seconds. What is the
final velocity?
Explanation:
s = ut + 1/2 a t^2
375 = 0 * 5 + 1/2 * a * (5)^2
375 = 1/2 * a * 25
a = 375*2/25
a = 15* 2
a = 30m/sec^2
v = u + at
v = 0 + 30 * 5
v = 150 m/sec
hope it helps you
My Lou Vee Air Car's propeller rotates, but it does not move the car forward. Can someone please help?? This is due on Monday!
Answer:
The force to get the plane moving, and to balance the friction so it does not stop, is provided by the propeller. However, the wheels provide the acceleration of the car.
Explanation:
Which two of the following actions would
result in a guitar string sounding a lower note
when plucked?
A Loosening the string
B Tightening the string
C Shortening the string
D Using a heavier string
Identify the 3 types of energy transfer shown in the diagram.
Answer:
1.Conduction.
2.Convection.
3.Radiation.
Explanation:
I'm sure it's correct
Why is the Earth generally warmer at the equator than at the poles?
Answer: The Sun's energy is more concentrated on the equator than the poles. This is because the Sun's energy (in the form of warmth) is more direct at the equator, and less direct at the poles.
Explanation: You can see this with a flashlight. When you point the flashlight directly toward a tale, the light is very concentrated and right. However, when you point the flashlight toward the table at an angle, the light becomes more spread out and less concentrated. This is why even though sometimes the North Poles and South Poles have 24 hours of sunlight, it never actually reaches a high temperature and instead, keeps it's cold temperature.
Type the most appropriate SI base unit (with a specific prefix as needed) for expressing each of the following.?(a) the mass of a sports car (b) the distance from your home to your school (c) the mass of an elephant (d) the diameter of a large pizza (e) a semester at your school (f) the time it takes for light to travel from the sun to the earth (g) the time it takes to fly from New York to California (h) your mass (i) the length of the Prime Meridian (j) your height
Answer:
Explanation:
Standard International (SI) units of measurement is the acceptable global units of measure for physical quantities. they are majorly fundamental units.
Thus,
(a) The mass of a sport car is measured in kilograms (kg).
(b) The distance from your home to your school is measured in meters (m).
(c) The mass of an elephant is measured in kilograms (kg).
(d) The diameter of a large pizza is measure in meters (m).
(e) A semester at your school is measured in weeks.
(f) The time for light to travel from the sun to the earth is expressed in seconds (s).
(g) The time it takes to fly from New York to California is in seconds (s).
(h) Your mass is measured in kilograms (kg).
(i) The length of the Prime Meridian is expressed in meters (m).
(j) Your height is expressed in meters (m).
The ball rolled 15 meters in 3 seconds. What was the speed of the ball?
Answer:
5 meter / sec.Explanation:
speed = distance / time
= 15 meters / 3 seconds
= 5 meter / sec.
Answer:5/sec
Explanation:
A truck accelerates from 25 km/hr to 45 km/hr in 40 seconds. Calculate the average acceleration of the vehicle in m/s?.
Answer:
0.138889 m/s2
Explanation:
The average acceleration of the vehicle would be 0.139 meters/second².
What is acceleration?The rate of change of the velocity with respect to time is known as the acceleration of the object.
As given in the problem a truck accelerates from 25 kilometers/hour to 45 kilometers/hour in 40 seconds.
Let us first convert the velocities from kilometers/hour to meters/seconds
25 kilometers/hour ⇒ 25×1000/3600
= 6.94 meters/seconds
45 kilometers/seconds = 45×1000/3600
= 12.5 meters/seconds
acceleration = change in the velocity/time
=(12.5 -6.94)/40
=0.139 meters/second²
Thus, the acceleration of the truck would be 0.139 meters/second²
To learn more about acceleration from here, refer to the link;
https://brainly.com/question/16768483
#SPJ2
Which of the following best describes the velocity of an object? *
8 points
A. 30 m/s
B. 30 m to the East
C. 30 m/s to the East
D. 30 m
A. 30 m/s . . . speed
B. 30 m to the East . . . displacement
C. 30 m/s to the East . . . velocity
D. 30 m . . . distance
Critical Thinking Questions - Part II
1. Restate Newton's first law in terms of (a) acceleration and (b) change in velocity.
Anyone please help ASAP?????15 points
Answer:
go to my comment on your most recent question
Explanation:
Beatrice and the Elevator Beatrice, a middle school student, is visiting a very tall office building and notices that she feels heavier when the elevator car is traveling up and lighter when the elevator car is travelling down. After making these observations, Beatrice comes back to the building and stands on a bathroom scale that measures her weight as she travels up and down in the elevator.
Explanation:
The question is not complete, here is the complete question
"Beatrice and the Elevator Beatrice, a middle school student, is visiting a very tall office building and notices that she feels heavier when the elevator car is traveling up and lighter when the elevator car is traveling down. After making these observations, Beatrice comes back to the building and stands on a bathroom scale that measures her weight as she travels up and down in the elevator.
1. . What question is Beatrice trying to answer?
2. What is one variable Beatrice could change in her investigation? What might she figure out if this
variable was changed"
1. Beatrice is trying to observe the influence of the elevator movement on her weight, Hence the question is "will the elevator movement cause her weight to change"
therefore moving upward the reading on the scale will increase
Reading=mg+ma
downward
Reading will reduce
Reading=mg-ma
2. The independent variable is the acceleration due to gravity g=9.81m/s^2
while the dependent variables are
i. The elevators acceleration
ii. Beatrice's mass
please help!!!!!!!!!!
Answer:
C
Explanation:
three bricks means 3 times the weight, so 6/3=2
3. What is the velocity of a wave that has a frequency of 750 Hz and a wavelength of 45.7 cm?
Explanation:
v=(750)(45.7)
v=34275
or
v=(750)(0.457)
v=342.75
A force of 20 N acts on an object with a mass of 5 kg. What is the acceleration of the object?
Answer:
4m/s²Explanation:
according to newton's second law of motion F=m×athus, acceleration = Force/mass= 20/5. = 4 m/s² is the total accelerationhope it helps:)
A 2-kg object is moving with a speed of 4 m/s. How much net force is required to keep the object moving at this velocity? What would be the objects acceleration? Explain.
20 points ??? ASAP PLEASE HELP
Answer:
Newton's second law states that the acceleration of an object is directly related to the net force and inversely related to its mass. Acceleration of an object depends on two things, force and mass. This shows that the bowling experiences a much greater force.
Explanation: that is the explanation
The force of 5N south acts concurrently with force of 5N 30 degrees South of East
A. Draw the diagram - TAIL to TAIL
B. Label both vectors (see page one for example)
C. Draw and LABEL the resultant and equilibrant
D.Find the magnitude and direction of the resultant and equilibrant
(scale: 1cm = 1N)
Answer:
The magnitude and direction of the resultant is 8.66 N and [tex]60^{\circ}[/tex] south of East.
The magnitude and direction the equilibrant is 8.66 N and [tex]60^{\circ}[/tex] North of West respectively.
Explanation:
Let
[tex]P=5\ \text{N}\ \text{south}[/tex]
[tex]Q=5\ \text{N}\ 30^{\circ}\ \text{south of east}[/tex]
[tex]\theta[/tex] = Angle between P and Q = [tex]60^{\circ}[/tex]
Magnitude of resultant
[tex]R=\sqrt{P^2+Q^2+2PQ\cos\theta}\\\Rightarrow R=\sqrt{5^2+5^2+2\times 5\times 5\cos60^{\circ}}\\\Rightarrow R=8.66\ \text{N}[/tex]
Direction is given by
[tex]\theta=\tan^{-1}\dfrac{Q\sin\theta}{P+Q\sin\theta}\\\Rightarrow \theta=\tan^{-1}\dfrac{5\sin60^{\circ}}{5+5\sin60^{\circ}}\\\Rightarrow \theta=30^{\circ}[/tex]
The magnitude and direction of the resultant is 8.66 N and [tex]30^{\circ}+30^{\circ}=60^{\circ}[/tex] south of East.
The magnitude and direction the equilibrant is 8.66 N and [tex]60^{\circ}[/tex] North of West.
can y’all please help me with this 3 part question?
Answer:
Vf = 210 [m/s]
Av = 105 [m/s]
y = 2205 [m]
Explanation:
To solve this problem we must use the following formula of kinematics.
[tex]v_{f} =v_{o} +g*t[/tex]
where:
Vf = final velocity [m/s]
Vo = initial velocity = 0 (released from the rest)
g = gravity acceleration = 10 [m/s²]
t = time = 21 [s]
Vf = 0 + (10*21)
Vf = 210 [m/s]
Note: The positive sign for the gravity acceleration means that the object is falling in the same direction of the gravity acceleration (downwards)
The average speed is defined as the sum of the final speed plus the initial speed divided by two. (the initial velocity is zero)
Av = (210 + 0)/2
Av = 105 [m/s]
To calculate the distance we must use the following equation of kinematics
[tex]v_{f} ^{2} =v_{o} ^{2} +2*g*y\\\\(210)^{2} = 0 + (2*10*y)[/tex]
44100 = 20*y
y = 2205 [m]
Define acceleration. Give its mathematical formula and SI unit. When is acceleration of a body negative? Give two examples of situations in which acceleration of the body is negative.
Answer:
The rate of change of velocity of a moving body is called acceleration. mathematical formula of Acceleration = Final velocity-Initial velocity
________________________
Time taken
SI Unit of Acceleration is m/s2. If the Velocity of a moving body decreases, it's acceleration will be negative. Two examples of situations in which acceleration of the body is negative are ÷
* Applying brakes * When a ball is thrown upward it experiences a negative AccelerationIf a rock is dropped from the top of a tower at the front of it and takes 3.6 seconds to hit the ground. Calculate the final velocity of the penny in m/s. What is the height of the tower?
Answer:
35.28m/s; 63.50m
Explanation:
Given the following data;
Time, t = 3.6 secs
Since it's a free fall, acceleration due to gravity = 9.8m/s²
Initial velocity, u = 0
To find the final velocity, we would use the first equation of motion;
[tex] V = u + at[/tex]
Substituting into the equation, we have;
[tex] V = 0 + 9.8 * 3.6[/tex]
V = 35.28m/s
Therefore, the final velocity of the penny is 35.28m/s.
To find the height, we would use the second equation of motion;
[tex] S = ut + \frac {1}{2}at^{2}[/tex]
Substituting the values into the equation;
[tex] S = 0(3.6) + \frac {1}{2}*9.8*(3.6)^{2}[/tex]
[tex] S = 0 + 4.9*12.86[/tex]
[tex] S = 0.5 *36[/tex]
S = 63.50m
Therefore, the height of the tower is 63.50m.
How did einstines and Newton’s theory’s differ in terms of explaining the cause of gravity
Answer: in the Newton concluded that objects fall because they are pulled by Earth's gravity. Einstein's interpretation was that these objects do not fall.
Explanation: These objects and Earth just freely move in a curved spacetime and this curvature is induced by mass and energy of these objects. - I HOPE THAT HELPED!!