1) If a projectile launched at a speed of 20m/s above the horizontal axis of an angle 53 ;(usin g=10mls sin 53=0.8 cos 53=0.6)
find
a the displacement at 2sec
b) the velocity of 2sec
c) total time
d) maximum time
e) Range
f) maximum height
Answer:
(a) 26.83 m
(b) 12.65 m/s
(c) 3.2 seconds
(d) 3.2 seconds
(e) 38.4 m
(f) 12.8 m
Explanation:
Given that a projectile launched at a speed of 20m/s above the horizontal axis at an angle of 53 degrees.
The vertical component of the velocity in the upward direction,
u= 20 sin 53= 20 x 0.8 = 16 m/s.
The horizontal component of the initial velocity,
s=20 cos53 = 20x0.6=12 m/s.
As the gravitational force acts in the vertical direction, so it will only change the vertical component of the initial velocity while the horizontal component of the initial velocity remains unchanged.
(a) The displacement at 2 seconds:
The horizontal distance covered in 2 seconds = 12x2= 24 m
By using the equation of motion, s= ut +1/2 at²
Here, a= -10 m/s² (as g=10m/s² acts in the downward direction)
the vertical displacement s= 16x2- 1/2 x 10 x 2²=12 m
Hence, the displacement after 2 seconds = [tex]\sqrt{24^2+12^2}[/tex]=26.83 m
(b) The velocity at 2 seconds:
As the horizontal component of the velocity is not changing, so the horizontal component of the velocity = 12 m/s
By using the equation of motion, v=u+at
The vertical component of the velocity, v= 16 - 10x2=-4m/s
The negative sign shows that the vertical component of the velocity is in the downward direction.
So, the the velocity at 2 seconds = 12 i - 4 j m/s
The magnitude of the velocity = [tex]\sqrt{12^2+(-40^2}[/tex]=12.65 m/s
(c) Total time of flight:
Total time of flight = 2 x (time to reach the maximum height)
At maximum height, the vertical component of the velocity = 0
So, by using the equation of motion, v=u+at
0= 16-10 t
t= 16/10=1.6 seconds
Hence, the total time of flight= 2 x 1.6 = 3.2 seconds.
(d) Maximum time:
This is the same as the total time of flight, so the maximum time = 3.2 seconds.
(e) Range:
Range = Horizontal component of the velocity x total time of flight
= 12 x 3.2 = 38.4 m
(f) Maximum height:
As the time to reach the highest point = 1.6 seconds
So, by using the equation of motion s = ut + 1/2 at²
The maximum height, s = 16 x 1.6 + 1/2 (-10)1.6² =12.8 m
Hence, the maximum height is 12.8 m.
pls help me w this, I've been doing this since 5 minutes ago
Answer:
t=0.0625s
Explanation:
F=number of swings/time taken
DATA
Frequency=4.0Hz
number of swings from Q to R
=1/4
time taken=?
Frequency=number of swings/time taken
make t the subject of the formula
t=n/f
substitute the given date
t=0.25/4.0
t=0.0625s
option A is collect
Ethics are deliberately learned from the family. Please select the best answer from the choices provided
Answer:
what are the choices provided?
Explanation:
Answer:
True
Explanation:
On Edg
Which frequency would be the third harmonic in a series for an open-pipe resonator if the fundamental is 440 Hz
Answer:
1320 Hz
Explanation:
The third harmonic is given as 3fo, where fo is the fundamental frequency.
The fundamental frequency is the lowest frequency that can occur in a pipe. In an open pipe, both even and odd harmonics occur which are multiples of the fundamental frequency fo. Hence the harmonics in an open pipe are; 2fo, 3fo,4fo..... etc.
For the third harmonic; 3fo = 3 (440 Hz) = 1320 Hz
Acceleration is a change in speed or direction over time. In what two ways does the sled accelerate as it descends?
Answer:
By force and sloppy surface.
Explanation:
By applying force on the sled and slope of the path are the two ways the sled accelerate as it descends. If there is more friction between sled and the ground then force is required to push the sled to move downward while on the other hand, if the path on which sled moves is sloppy then it will move automatically without the use of force, so these two ways can accelerate the sled.
An object is falling from a height of d and reaches a final velocity of vf. Calculate velocity when the object has fallen a distance d/2.
Answer:
The final velocity, [tex]v_{f}[/tex], is gd.
Explanation:
The condition here is a free falling object. Thus from the third equation of motion under free fall, we have;
[tex]v_{f}[/tex] = [tex]v_{i}[/tex] + 2gs
where [tex]v_{f}[/tex] is the final velocity of the object, [tex]v_{i}[/tex] is the initial velocity of the object, g is the gravitational force and s is the height.
Since the object falls from a height of d, then [tex]v_{i}[/tex] = 0 m/s, and s = d.
So that;
[tex]v_{f}[/tex] = 0 + 2gd
= 2gd
[tex]v_{f}[/tex] = 2gd
When the distance is [tex]\frac{d}{2}[/tex], [tex]v_{i}[/tex] = 0 m/s.
Then;
[tex]v_{f}[/tex] = 2g[tex]\frac{d}{2}[/tex]
[tex]v_{f}[/tex] = g x d
When the object falls through the height [tex]\frac{d}{2}[/tex], then the final velocity is gd.
A 325kg box is pulled across a level frictionless surface. What is the weight of the box.
Answer:
the answer is that you will never be able to find two pretty bestfriends
Find the mass of a copper block with heat capacity 50j/kg,(specific heat capacity of copper=400j/kg)
A car changes chemical energy from fuel into thermal energy and ________ energy.
Answer:
Mechanical energy
Explanation:
A car changes chemical energy from fuel into thermal energy and mechanical energy.
Mechanical energy can be defined as the type of energy that is possessed by an object due to its motion or position. Mechanical energy is the sum of potential energy and kinetic energy, that is, the sum of energy in motion and stored energy. Examples of mechanical energy includes driving a car, riding a bicycle, listening to music etc.
Types of mechanical energy
1. Motion energy (kinetic energy)
2. Stored energy(potential energy)
Mechanical energy = Kinetic energy + Potential energy
A plane lands and comes to a complete stop. If the plane covers 200 m and decelerates at 7.5 m/s2 , what was the planes initial velocity as it touched the runway?
Answer:
The initial velocity of the plane is 54.77 m/s
Explanation:
Given;
distance covered by the plane, d = 200 m
deceleration of the plane, a = - 7.5 m/s²
The initial velocity of the plane is given by the following kinematic equation;
v² = u² + 2ad
where;
v is the final velocity of the plane when the plane comes to a complete stop = 0
u is the initial velocity of the plane
0 = u² + 2(-7.5 x 200)
0 = u² - 3000
u² = 3000
u = √3000
u = 54.77 m/s
Therefore, the initial velocity of the plane is 54.77 m/s
You are standing on a moving bus, facing forward, and you suddenly fall forward. You can imply form this that the bus’s
1 point
A leak in a swimming pool allows 2.50 liters to flow out every minute. How
many gallons leak out in week? (There are 0.946 liters per quart and 4
quarts per gallon.) *
O 910. gallons
O 12 700 gallons
0 7 140 gallons
6 660 gallons
Answer:
66.6 G
Explanation:
How does seeing an object compare with seeing a shadow?
Answer: shadows are not parts of their objects—we can change a shadow without changing the object
Answer:
So we can see objects by seeing silhouettes. By contrast, shadows are not parts of their objects—we can change a shadow without changing the object (say, by putting another object in between the object and the light source). So we cannot see objects by seeing shadows.
.
A student used a video camera to record another student dropping a marble through water in a graduated cylinder. The students watched the video in slow motion and made the observations shown below.
marble, drop, experiment, marble, graduated, cylinder, water, 1, speed, increases, 2, speed, decreases, 3, speed, is, constant,
During which part or parts of the marble’s fall did the marble experience unbalanced forces?
Answer:
Parts 1 and 2 only is the best answer.
Explanation:
Hope this helps!
Answer: 1 and 2
Explanation:
PLEASEEE HELPPP!!!
A mover slides a refrigerator weighing 650 N at a constant velocity across the floor
a distance of 8.1 m. The force of friction between the refrigerator and the floor is
230 N. If the work was done in 55 seconds, what is the power of the mover?
Answer:
very strong
Explanation:
the answer is something
Two lamps rated 60W; 240V and 100W, 240Vrespectively are connected in series to a 240V power source. Calculate;
a) The resistance of each lamp.
b) The effective resistance of the circuit.
c) The current passing the lamps. pls answer correctly
Answer:
See the answers below.
Explanation:
The total power of the circuit is equal to the sum of the powers of each lamp.
[tex]P=60+100\\P=160 [W][/tex]
Now we have a voltage source equal to 240 [V], so by means of the following equation we can find the current circulating in the circuit.
[tex]P=V*I[/tex]
where:
P = power [W]
V = voltage [V]
I = current [amp]
[tex]I = P/V\\I=160/240\\I=0.67 [amp][/tex]
So this is the answer for c) I = 0.67 [amp]
We know that the voltage of each lamp is 240 [V]. Therefore using ohm's law which is equal to the product of resistance by current we can find the voltage of each lamp.
a)
[tex]V=I*R[/tex]
where:
V = voltage [V]
I = current [amp]
R = resistance [ohms]
Therefore we replace this equation in the first to have the current as a function of the resistance and not the voltage.
[tex]P=V*I\\and\\V = I*R\\P = (I*R)*I\\P=I^{2}*R[/tex]
[tex]60 = (0.67)^{2}*R\\R_{60}=133.66[ohm] \\and\\100=(0.67)^{2} *R\\R_{100}=100/(0.66^{2} )\\R_{100}=225 [ohm][/tex]
b)
The effective resistance of a series circuit is equal to the sum of the resistors connected in series.
[tex]R = 133.66 + 225\\R = 358.67 [ohms][/tex]
I need help in Physics pls help me!
20 points for CORRECT ANSWER!!!
Answer:
V = 3.65 m/s
Explanation:
Cuatro niños jalan de manera separada un mismo carrito de baleros con un mismo desplazamiento, pero uno con un ángulo de 45°, otro con un ángulo de 35°, otro de 20° y el ultimo con un ángulo de 0°, medidos con respecto al eje horizontal. ¿Cuál de los cuatro realiza un mayor trabajo, si la fuerza que se aplica cada uno de ellos es la misma? Selecciona el ángulo:
Answer:
El niño que aplica una fuerza a un ángulo de 0º realiza el mayor trabajo.
Explanation:
Si consideramos que las fuerzas aplicadas en el carrito de baleros es constante tanto en magnitud como en dirección, el trabajo realizado por cada niño ([tex]W[/tex]), medido en joules, puede definirse mediante la siguiente expresión:
[tex]W =F\cdot x\cdot \cos \alpha[/tex] (1)
Donde:
[tex]F[/tex] - Magnitud de la fuerza aplicada por el niño, medida en newtons.
[tex]x[/tex] - Distancia desplazada por el carrito de baleros, medida en metros.
[tex]\alpha[/tex] - Dirección de la fuerza aplicada, medida en grados sexagesimales.
De (1) tenemos que la fuerza efectiva que empuja el carro es:
[tex]F_{e} = F\cdot \cos \alpha[/tex]
La fuerza aplicada por cada niño es despejada:
[tex]F = \frac{F_{e}}{\cos \alpha}[/tex]
A mayor ángulo, tenemos un menor valor del coseno y, por ende, mayor valor de la fuerza aplicada. Ahora, el mayor trabajo realizado se realiza con el menor ángulo posible y bajo esta consideración, el niño que aplica una fuerza a un ángulo de 0º realiza el mayor trabajo.
If there are oncoming cars to the left of you and a child on a bike to the right, what is the correct action to take
Answer:
Give the child a lot of room to your side, which may mean moving closer to the oncoming vehicles.
Explanation:
I majored in Physics.
hello, why do all electromagnetic waves travel at the same speed in vacuum?
Answer:
due to the magnetic field
Explanation:
magnetic field is the same in the vacuum
Jack travelled 360 km at an average speed of 80 km/h. Elaine took 1.5 hours more to complete the same amount of distance. What was Elaine’s average speed for the whole journey? _____km/h and m/s
How many significant figures are in the number 08.40001
07
3
O 6
O 5
Answer:
5
Explanation:
every number after the decimal
How did Galileo increase public support for Copernicus’s model?
by publishing his work in Italian
by using data collected by Tycho Brahe
by explaining why planets appear to move backward
by arguing that Earth’s rotation makes objects appear to move in the sky
Galileo increases public support for Copernicus's model by publishing his work in Italian. Thus option a is correct.
Copernicus's model has been the heliocentric model of the universe given by Nicolaus Copernicus. According to the model, the sun has been the center of the universe, and the planets are revolving around the Sun in a circular path, and at a constant speed.
This idea of Copernicus has been against religious belief and thus has not been accepted. However, the development of Keplar's law helps in the better understanding of Copernicus's model.
Galileo increases public support for Copernicus's model by publishing his work in Italian. Thereby finally the model has been published in 1543. Thus option a is correct.
For more information about Copernicus's model, refer to the link:
https://brainly.com/question/12712605
Answer: The answer is: by publishing his work in Italian
Explanation: credit to the guy above me!
Have a great day!
-Sunny
Assuming that it could maintain the same acceleration at higher speeds, how long would it take the car to go from 0 to 120 mph
The question is incomplete, the complete question is;
A car can go from 0 to 60 mph in 7.0 s. Assuming that it could maintain the same acceleration at higher speeds, how long would it take the car to go from 0 to 120 mph? A. 10 s B. 14 s C. 21 s D. 28 s
Answer:
B
Explanation:
We have;
vo = 0 m/s
v1 = 60 mph or 26.8 m/s
v2 = 120 mph or 53.6 m/s
t1 = 7s
To obtain a
v1 = vo + at1
but vo = 0 m/s
a = v1/t1 = 26.8 m/s/7s = 3.8 ms-2
To obtain t2 for the car;
v2 = vo + at2
but vo = 0 m/s
t2= v2/a = 53.6m/s/3.8ms-2
t2 = 14.1 s
Choose the answer that is most descriptive of the Solar System. Sun, planets, moons, asteroids, comets Nebulas, star clusters, super nova, black holes, binary stars Jupiter, Neptune, Saturn, Uranus, dwarf planets Jupiter, Great Red Spot, 8 regular moons, ±58 irregular moons
Answer:
The correct option is;
Sun, planets, moons, asteroids, comets
Explanation:
The Solar System consists of the system of celestial bodies bound gravitationally to the Sun, which includes the 8 regular planets, 2 dwarf planets, 796, 354 known minor planets, 4,143 comets, moons, which are natural satellites, an asteroid belt, which consists of a belt of rock and metal containing celestial bodies moving in a belt round the Sun
A 50.0kg skydiver experience a 740newton air resistance force determine her acceleration
please someone help me
Answer:
a = - 5 [m/s²].
Explanation:
To solve this problem we must use Newton's second law, which tells us that the sum of forces on a body is equal to the product of mass by acceleration.
∑F = m*a
where:
F = resultant force [N] (units of Newtons)
m = mass = 50 [kg]
a = acceleration = 9.81 [m/s²]
For this particular problem, the only forces acting are the force of gravity acting down with negative sign, while the force of air opposes the fall, in this way it is positive.
[tex]f_{air}-F_{grav}=-m*a[/tex]
As the movement is pointing down the acceleration will be taken as negative.
[tex]740-(50*9.81)=-50*a\\740-490.5 = -50*a\\249.5 = -50*a\\a = - 5 [m/s^{2} ][/tex]
We should note that in this case, the acceleration has a negative sign, this means that the force of the air makes the skydiver move upwards.
please answer asignment due today
Answer:
Give me some time okkkk
Help please ASAP !! Thanks
Answer:
I think its C
Explanation:
If Earth orbited the Sun in 9 months instead of 12, then, compared with a sidereal day, a solar day would be
Answer:
longer
Explanation:
The relationship between the solar day and sidereal is as follows:
The length of the sidereal day is
= (Solar day) (solar year ÷ solar year + 1 day)
As it can be seen that the day i.e. solar its length would be greater as compared with the sidereal day.
In the case when the earn orbited the sun in 9 months rather than 12 so here the sidereal day would be the similar but the solar day would be longer as compared with the original one
---Spring Question---
A 0.84 kg ball is held at rest against a spring (k = 142 N/m) that has been compressed 0.06 m. The ball and spring are on a table and the ball is 2.0 m above the ground. If friction between the ball and the table is negligible, then how far from the edge of the table (in meters) will the ball hit the ground?
Answer:
The distance from the edge of the table at which the ball will hit the ground is approximately 0.49 meters
Explanation:
The mass of the ball = 0.84 kg
The spring constant k = 142 N/m
The compression of the spring = 0.06
Therefore, by conservation of energy, we have;
The potential energy of the spring = The kinetic energy given to the ball
The potential energy of the spring = 1/2 × k × x² = 1/2 × 142 × 0.06² = 0.2556
The potential energy of the spring = 0.2556 J
The kinetic energy given to the ball = 1/2 × m × v²
Where;
v = The final velocity of the ball
Substituting gives;
1/2 × 0.84 × v² = 0.2556
∴ v = √(0.2556/(1/2 × 0.84)) ≈ 0.78
The final velocity of the ball = v ≈ 0.78 m/s
The height of the ball above the ground, h = 2.0 m
Therefore, we have;
The time, t, it takes the ball to touch the ground from the 2.0 m height, h, is given as follows;
h = 1/2·g·t²
t = √(2·h/g)
Where;
g = The acceleration due to gravity = 9.81 m/s²
∴ By substitution, we have;
t = √(2 × 2/9.81) ≈ 0.63855
t ≈ 0.63855 s
The distance from the edge of the table at which the ball will hit the ground = The horizontal distance covered during before the ball hits the ground
The horizontal distance covered during before the ball hits the ground = The (horizontal) velocity of the ball × The time it takes the ball to touch the ground
∴ The horizontal distance covered during before the ball hits the ground = 0.78 × 0.62855 ≈ 0.490269 ≈ 0.49
The distance from the edge of the table at which the ball will hit the ground = The horizontal distance covered during before the ball hits the ground ≈ 0.49 m