A place kicker must kick the football from a point [06] m from the goal and clear a bar 3.00 m above the ground. The ball leaves the ground with a speed of 20.0 m/s at an angle of 53.0 degrees above the horizontal. (a) By how much (m) does the ball clear (positive value) or fall short (negative value) of the cross bar? (This is vertical distance above or below the cross bar.) (b) When it gets to the cross bar, what is the vertical component of the ball’s velocity (m/s)? (Is it rising or falling-pay attention to the sign?)

Answers

Answer 1

Answer:

Explanation:

Horizontal component of initial velocity of throw = 20 cos 53 = 12 m /s

Vertical component = 20 sin 53 = 15.97 m /s

Distance to be travelled horizontally = 6 m .

time taken by ball to travel this distance = 6 / 12 = 0.5 s

vertical displacement during this period can be calculated as follows .

Initial vertical velocity = 15.97 m /s

time of travel = .5 s

acceleration = - 9.8 m /s²

s = ut - 1/2 g t²

= 15.97 x .5 - .5 x 9.8 x 0.5²

= 7.985 - 1.225

= 6.76 m

Goal post is 6 m high , so ball will cross the goal post .76 m or 76 cm above cross bar  .

b ) vertical component of ball when it crosses the goal post . Let it be v .

v = u - gt

Applying this formula for vertical movement ,

v = 15.97 - 9.8 x .5

= 15.97 - 4.9

= 11.07 m /s .


Related Questions

If a solid metal sphere and a hollow metal sphere of equal diameters are each given the same charge, the electric field (E) midway between the center and the surface is...A. greater for the solid sphere than for the hollow sphere.B. greater for the hollow sphere than for the solid sphere.C. zero for bothD. equal in magnitude for both, but one is opposite in direction from the other.

Answers

Answer:

C. zero for both

Explanation:

In case of solid metal sphere , when it is given any charge , all the charges are transferred on the surface and within surface no charge exists . In case of hollow metal sphere , all charges reside on surface . In this way , in both solid and hollow sphere , all charge reside on the surface and no charge resides inside it . Hence due to absence of any charge inside  , there is no electric field inside the sphere in both the cases .  

Hence in both the case electric field is zero .

option C is correct .

50 points Two waves combine with constructive interference. What must be true of the
combined wave that forms?
A. It has a lower frequency than that of the original waves.
B. It has a higher amplitude than that of the original waves.
C. It has a higher frequency than that of the original waves.
D. It has a lower amplitude than that of the original waves.

Answers

Answer:

it has a higher amplitude than that of the original waves

Explanation:

trust me its right

The two waves combined with constructive interference have a higher amplitude than the original wave.

Which wave has the highest amplitude?

High energy waves are characterized by high amplitude. Low energy waves are characterized by their small amplitude. As explained in Lesson 2, wave amplitude is the maximum amount of particle movement on a medium from a resting position.

What are superposition and interference?

Superposition is a combination of two waves in the same place. Constructive interference occurs when two identical waves interfere in phase. Destructive interference occurs when two identical waves are exactly out of phase and overlap.

Learn more about higher amplitude waves at

https://brainly.com/question/19036728

#SPJ2

A toy car accelerates uniformly from rest at a constant rate. The car travels 1.0 meters in 1.0 seconds. The acceleration of the car is ________ meters per second squared.

Answers

Answer:

a=1m/s^2

Explanation:

1÷1÷1=1m/s^2

The deepest part of the ocean is the Challenger Deep, at 10,900 m. The depth was first measured in 1875 by the HMS Challenger by depth sounding (which does not involve sound waves). If you were to measure the depth by echo sounding (which does involve sound), what would you expect the time for a sound pulse at the surface to return in s, naively assuming a constant sound velocity throughout the ocean

Answers

Answer:

 t = 14.53 s

Explanation:

The speed of a wave is constant and is given by

         v = [tex]\sqrt{ \frac{B}{ \rho} }[/tex]

in this exercise they indicate that we assume the constant velocity, therefore we can use the uniform motion relations

          v = x / t

           t = x / v

in this case the sound pulse leaves the ship and must return so the distance is

          x = 2d

where d is the ocean depth d = 10900m and the speed of sound in seawater is v = 1500 m / s

         

let's calculate

           t = 2 10900/1500

           t = 14.53 s

A 7300 kg rocket blasts off vertically from the launch pad with a constant upward acceleration of 2.20 m/s2 and feels no appreciable air resistance. When it has reached a height of 575 m , its engines suddenly fail so that the only force acting on it is now gravity. Part A What is the maximum height this rocket will reach above the launch pad

Answers

Answer:

Explanation:

We shall first calculate the velocity at height h = 575 m .

acceleration a = 2.2 m /s²

v² = u² + 2 a s

u is initial velocity , v is final velocity , s is height achieved

v² = 0 + 2 x 2.2 x 575

v = 50.3 m /s

After 575 m , rocket moves under free fall so g will act on it downwards

If it travels further by height H

from the relation

v² = u² - 2 g H

v = 0 , u = 50.3 m /s

H = ?

0 = 50.3² - 2 x 9.8 H

H = 129.08 m

Total height attained by rocket

= 575 + 129.08

= 704.08 m .

A skydiver is using wind to land on a target that is 50 m away horizontally. The skydiver starts from a height of 70 m and is falling vertically at a constant velocity of 7.0 m/s downward with their parachute open (terminal velocity). A horizontal gust of wind helps push them towards the target. What must be their total speed if they want to just hit their target?

Answers

Answer:

Answer:

15.67 seconds

Explanation:

Using first equation of Motion

Final Velocity= Initial Velocity + (Acceleration * Time)  

v= u + at

v=3

u=50

a= - 4 (negative acceleration or deceleration)  

3= 50 +( -4 * t)

-47/-4 = t

Time = 15.67 seconds

We have that the speed  must be at the speed below if they want to just hit their target

From the Question we are told that

Distance [tex]d=50m[/tex]

Height [tex]h=70m[/tex]

Constant Velocity [tex]v= 7.0 m/s[/tex]

Generally the equation for the time  is mathematically given as

[tex]T=\frac{h}{v}\\\\T=\frac{70}{7}\\\\T=10s[/tex]

Therefore

The velocity required to make horizontal movement is

[tex]V=\frac{d}{T}\\\\V=\frac{50}{10}\\\\V=5m/s[/tex]

Given that

Velocity on the Vertical axis is

[tex]v_y=7m/s[/tex]

Velocity on the  horizontal axis is

[tex]v_x=5m/s[/tex]

Therefore resultant speed

[tex]v_r=\sqrt{v_x^2+V_y^2}\\\\v_r=\sqrt{(5)^2+(7)^2}[/tex]

[tex]v_r=8.6023m/s[/tex]

In conclusion

[tex]v_r=8.6023m/s[/tex] must be their total speed if they want to just hit their target

For more information on this visit

https://brainly.com/question/17127206

5. An astronaut has a mass of 65kg where the gravitational field strength is 10N/kg
a. Calculate the weight of the astronaut on earth
[3]

Answers

Answer:  a) weight on Earth = mass of the object and gravity n the Earth. = 65*10 = 650 kg.

Explanation:

An astronaut has a mass of 65 kg on Earth where the gravitational field strength is 10 N kg A calculate the astronaut's weight on Earth

          hope this helps :)

Answer:

650

Explanation:

use the equation

weight = gm

plsss answer this plsss answer this plsss answer this plsss answer this ​

Answers

Answer:

I dont see file

dndndndbnfbfbfbfbfbf

Answer:

ye ek rod h or electric ⚡ field h P point

Pluto has a radius of 1.15 x 10^6 m, and its acceleration due to gravity is 0.61 | m/s^2. What is Pluto's mass?​

Answers

so we will use Newton's gravitational law :

gravitational acceleration = G*m/r^2  

G is the gravitational constant = G = 6.673×10^-11 N m^2 kg^-2  

after substitution :  

6.673×10^-11 * m / (1.15 x 10^6)^2 = 0.61

= 5.04575*10^-23 * m = 0.61

dividing over 5.04575*10^-23 :

m = 1.20894*10^22 kg

pls give me brainliest

A pendulum has a period of 5.14s and a length of 0.25m. What is the acceleration
due to gravity? *

Answers

Answer:

Acceleration due to gravity, g = 2.68m/s²

Explanation:

Given the following data;

Period = 5.14s

Length = 0.25m

To find acceleration due to gravity, g;

[tex] Period, T = 2 \pi \sqrt {lg} [/tex]

Substituting into the equation, we have;

[tex] 5.14 = 2*3.142 \sqrt {0.25g} [/tex]

[tex] 5.14 = 6.284 \sqrt {0.25g} [/tex]

[tex] \frac {5.14}{6.284} = \sqrt {0.25g} [/tex]

[tex] 0.8180 = \sqrt {0.25g} [/tex]

Taking the square of both sides

[tex] 0.8180^{2} = 0.25g [/tex]

[tex] 0.6691 = 0.25*g[/tex]

[tex] g = \frac {0.6691}{0.25} [/tex]

Acceleration due to gravity, g = 2.68m/s²

Starting from rest, a wheel with constant angular acceleration turns through an angle of 25 rad in a time t. What will its angular velocity be after 3t?

Answers

Answer:

θ = 225 rad

Explanation:

given data

angle = 25 rad

to find out

angular velocity after 3t?

solution

let angular acceleration α in t

θ = ω × t + 0.5 × α × t²        ........................1

here ω  = 0 (initial velocity )

so put this value here

25 = 0 + 0.5 × α × t²             ..........................2

α = 25 ÷ (0.5 t²)

α = 50 ÷ t²                            .........................3

now here we take in 3t

θ = ω × 3t + 0.5 × α × (3t)²

for ω  = 0

θ = 0 + 0.5 × α × 9t²

now put value in eq 2

so

θ = (0.5) ×  (50 ÷ t²) ×  (3t)²

θ = 25 × 9

θ = 225 rad

If the car has a mass of 0.2 kg, the ratio of height to width of the ramp is 12/75, the initial displacement is 2.25 m, and the change in momentum is 0.58 kg*m/s, how far will it coast back up the ramp before changing directions

Answers

Answer:

     l = 0.548 m

Explanation:

For this exercise we compensate by finding the speed of the car

         p = m v

         v = p / m

         v = 0.58 / 0.2

         v = 2.9 m / s

this is how fast you get to the ramp, let's use conservation of energy

starting point. Lowest point

         Em₀ = K = ½ m v²

final point. Point where it stops on the ramp

         [tex]Em_{f}[/tex] = U = m g h

  mechanical energy is conserved

          Em₀ = Em_{f}

          ½ m v² = m g h

           h = [tex]\frac{m v^2}{2 g}[/tex]

let's calculate

          h = [tex]\frac{0.2 \ 2.9^2}{2 \ 9.8}[/tex]

          h = 0.0858 m

to find the distance that e travels on the ramp let's use trigonometry, we look for the angle

          tan θ = y / x

          tan θ = 12/75 = 0.16

          θ = tan⁻¹ 0.16

          θ = 9º

therefore

           sin 9 = h / l

           l = h / sin 9

           l = 0.0858 / sin 9

           l = 0.548 m

PLEASE HELP GIVING BRAINLIEST ANSWER
Explain why your PE and KE are usually not both high at the same time (If PE is high then usually KE is low)

Answers

Potential energy is an object’s stored energy when it is not moving. Kinetic energy is an object’s energy in motion. You can’t be both moving and not moving at the same time, so PE and KE cannot be equal.

What school did Ronald McNair go to and what kind of science did he work in

Answers

Answer:

McNair graduated as valedictorian of Carver High School in 1967. In 1971, he received a Bachelor of Science degree in engineering physics, magna cu.m laude, from the North Carolina Agricultural and Technical State University in Greensboro, North Carolina.

A π meson of rest energy 139.6 MeV moving at a speed of 0.921c collides with and sticks to a proton of rest energy 938.3 MeV that is at rest. (a) Find the total relativistic energy of the resulting composite particle. (b) Find the total linear momentum of the composite particle. (c) Using the results of (a) and (b), find the rest energy of the composite particle.

Answers

Answer:

A) 1268 MeV

B)  299MeV/c

C) 1268 MeV

Explanation:

Given :

π meson rest energy = 139.6 MeV

Speed = 0.921c

proton at rest energy = 938.3 MeV

a) Find the total relativistic energy of resulting composite particle

E = E(meson) + E(proton)

  = [tex]\frac{(mc^2)_{meson} }{\sqrt{1-\frac{v^2}{c^2} } } + (mc^2)_{proton}[/tex]

  = [tex]\frac{139.6MeV}{\sqrt{1-\frac{(0.906c)^2}{c^2} } } + 938.3[/tex]

E = 1268 MeV

B) determine the total linear momentum of the composite particle

= 299MeV/c

attached below is the detailed solution

C) Determine the rest energy of the composite particle

E = 1268 MeV

In order for the eye to see an object _____ from the object myst be reflected to your eye.

Light or particle ?

Answers

Answer: light from the object

Explanation:

When light is reflected off an object like a lamp or a door is travels in a straight line but in a new direction so if the light enters our eyes we will see the object because our eyes can detect light

Which of the following is an example of Newton's Third Law?* O A stack of pennies will not move unless you flick them over. O Falling off of a skateboard after you run into a curb A ball hits the ground and the ground pushes up on it with the same force​

Answers

Answer:

A ball hits the ground and the ground pushes up on it

Explanation:

Newton's third law basically states that for every action, there's a reaction.

a ball hitting the ground would be the action. the ground pushing up on it with the same force is the reaction.

Hope this Helps!!! :)

A hiker walks 7.7 miles to the east in 3.6 hours, then turns around and walks 2.1 miles to the west in 2.4 hours. What was the magnitude of her average velocity during the trip?

Answers

Answer:

2.18 miles per hour

Explanation:

Given:

A hiker walks 7.7 miles to the east in 3.6 hours.

A hiker walks 2.1 miles to the west in 2.4 hours

To find: magnitude of average velocity during the trip

Solution:

Total distance = 7.7 + 2.1 = 9.8 miles

Total Time = 2.1 + 2.4 = 4.5 hours

Average velocity = Total distance ÷ Total Time =[tex]\frac{9.8}{4.5}=2.18[/tex] miles per hour


A lunar eclipse occurs when the Moon passes through Earth's

Answers

False, when the moon passes between the earth and sun it’s a solar eclipse and lunar eclipse happens when earth passes between the moon and sun

In traveling a distance of 2.3 km between points A and D, a car is driven at 83 km/h from A to B for t seconds and 41 km/h from C to D also for t seconds. If the brakes are applied for 4.4 seconds between B and C to give the car a uniform deceleration, calculate t and the distance s between A and B.

Answers

Answer:

- time t taken for car to travel is 64.57 s

- distance travelled between A and B is 1.4887 km

Explanation:

Given the data in the question;

[tex]U_{BC}[/tex] =  83 km/h = ( 83×1000 / 60×60) =  23.0555 m/s

[tex]U_{CD}[/tex] = 41 km/h = ( 41×1000 / 60×60) =  11.3888 m/s

now, we calculate the acceleration;

a =  (  [tex]U_{BC}[/tex] -  [tex]U_{CD}[/tex] ) / t

we substitute

a =  ( 23.0555 -  11.3888 ) / 4.4

a = 11.6667 / 4.4

a = 2.6515 m/s²

Now equation for displacement from BC

[tex]S_{BC}[/tex] =  [tex]U_{BC}[/tex]t + 1/2.at²

we substitute

[tex]S_{BC}[/tex] =  23.0555×4.4 + 1/2×a×(4.4)²

we substitute -2.6515m/s² for a

[tex]S_{BC}[/tex] =  23.0555×4.4 + 1/2×(-2.6515)×(4.4)²

= 101.4442 - 25.6665

[tex]S_{BC}[/tex] = 75.7792 m

Now, for total distance covered = 2.3km = ( 2.3×1000) = 2300m

so

[tex]S_{AB}[/tex] +  [tex]S_{BC}[/tex] +  [tex]S_{CD}[/tex]  =  2300 m

we substitute substitute

[tex]S_{AB}[/tex] +  75.7792 m +  [tex]S_{CD}[/tex]  =  2300 m

[tex]S_{AB}[/tex] +  [tex]S_{CD}[/tex] = 2300 - 75.7792

[tex]S_{AB}[/tex] +  [tex]S_{CD}[/tex]  = 2224.2208 m

so we substitute 23.0555t for [tex]S_{AB}[/tex]  and 11.3888t for  [tex]S_{CD}[/tex]  

23.0555t + 11.3888t  = 2224.2208

34.4443t = 2224.2208

t = 2224.2208 / 34.4443

t = 64.57 s

Therefore, time t taken for car to travel is 64.57 s

Distance Between A to B

[tex]S_{AB}[/tex]  = t ×  [tex]U_{AB}[/tex]

we substitute

[tex]S_{AB}[/tex]  = 64.57 s × 23.0555

[tex]S_{AB}[/tex]  = 1488.69 m

[tex]S_{AB}[/tex]  = 1.4887 km

Therefore, distance travelled between A and B is 1.4887 km

Pls help!!
1 example of a conductor and 1 example of a insulator in your EVERYDAY world.

Answers

Answer:

here

Explanation:

Examples of insulators include plastics, Styrofoam, paper, rubber, glass and dry air.

Examples of conductors include metals, aqueous solutions of salts

Conductor= Metals are good conductors of heat, therefore cooking utensils, kettles, irons, boilers, are always made up of iron, copper, Aluminum, or their alloys.


Insulators= oppose electrical current and make poor conductors. Some common conductors are copper, aluminum, gold, and silver. Some common insulators are glass, air, plastic, rubber, and wood.

Hope it helps! :3

A laser positioned on a ship is used to communicate with a small two man research submarine resting on the bottom of a lake. The laser is positioned 12 m above the surface of the water, and it strikes the water 20 m from the side of the ship. The water is 76 m deep and has an index of refraction of 1.33. How far is the submarine from the side of the ship

Answers

Answer:

84.1 m

Explanation:

Given :

The distance from the ship to submarine :

20 + y

Using Pythagoras :

Tan θ = opposite / Adjacent

Tan θ = 20 / 12

12 tan θ = 20

θ = tan^-1(20/12)

20

θ = 59.036°

The angle phi;

n1sinθ1 = n2sin θ

Sin 59.036 = 1.33 * sin phi

Sin phi = sinsin(59.04) ÷1.33

0.8574907 = 1.33 * sin phi

Sin phi = 0.8574907 / 1.33

Sin phi = 0.6447298

phi = sin(0.6447298

Phi = 40.15°

From Pythagoras :

y = 76tan40.15°

y = 76 * 0.8435707

y = 64.11

20 + y

20 + 64.11 = 84.11

I love buying physics toys. I recently broke out my new electromagnetic field meter and started playing with it. After turning it on, I noticed the device kept showing an electric field value of 200 N/C towards the ground, without being near anything obvious (e.g., an electronic device) that would be producing the electric field. I even took a long walk to check if the reading was somehow localized to my house, but I got the same result. How might you explain the reading (assuming the device is working properly)

Answers

Answer:

ionized particles from the sun.

* interactions in radiation belts.

* the friction of the planet in the solar wind

q = +9 10⁵ C

Explanation:

Due to being made up of matter, the planet Earth has a series of positive and negative charges, in general these charges should be balanced and the net charge of the planet should be zero, but there are several phenomena that introduce unbalanced charges, for example:

* ionized particles from the sun.

* interactions in radiation belts.

* the friction of the planet in the solar wind

This creates that the planet has a net electrical load

         

We can roughly calculate the charge of the planet

             E = k q / r²

             q = E r² / k

let's calculate

             q = 200 (6.37 10⁶)²/9 10⁹

              q = +9 10⁵ C

6. The petrol in a petrol can weighs 2000g. The density of petrol is 0.8g/cm3.
What is the volume of the petrol in the can in a) cm3 b)litres (1000cm3=1 litre)

Pls help :((

Answers

Answer:

a. 2500 cm³.

b. 2.5 litres.

Explanation:

Given the following data:

Density = 0.8g/cm³

Mass = 2000g

To find the volume of the petrol;

Density can be defined as mass all over the volume of an object.

Simply stated, density is mass per unit volume of an object.

Mathematically, density is given by the equation;

[tex]Density = \frac{mass}{volume}[/tex]

Making volume the subject of formula, we have;

[tex]Volume = \frac{mass}{density}[/tex]

Substituting into the equation, we have:

[tex]Volume = \frac{2000}{0.8}[/tex]

Volume = 2500 cm³

a. The volume of the petrol in the can in cubic centimeters (cm³) is 2000.

b. The volume of the petrol in the can in litres;

1000 cm³ = 1 litre

2500 cm³ = x litres

Cross-multiplying, we have;

1000x = 2500

x = 2500/1000

x = 2.5 litres.

Therefore, the volume of the petrol in the can in litres is 2.5.

. Why is it harder to stop an elephant accelerating at 1m/s2 than a rabbit accelerating at 1m/s2
(10 Points)
the elephant has more mass
the rabbit is faster
the rabbit has more mass
the elephant is faster

Answers

Answer:

this is about momentum p=mv

A, the elephant has more mass

A car starts from rest and accelerates uniformly at a rate of 2.0 meter per second squared for 4.0 seconds. During this time interval, the car traveled ________ meters.

Answers

Answer:

16

Explanation:

[tex] \frac{1}{2} \times 2 \times {4}^{2} = 16[/tex]

17. During a game of tug of war, two teams of students pull on opposite sides of a rope. During the
game, the rope begins to accelerate towards the left. What must be true about the forces acting on the
rope at the time of the acceleration towards the left?
A. The team pulling towards the right is pulling with a force greater than the team pulling towards the left.
B. The team pulling towards the right is pulling with a force equal to the team pulling towards the left.
C. The team pulling towards the right is pulling with a force less than the team pulling towards the left.
D. The team pulling towards the right stopped pulling the rope while the team pulling towards the left
continued

Answers

Answer:

c

Explanation:

The answer is letter c

A fan is set on a desk next to a stack of paper. The fan is turned on and then turned
on HIGH SPEED. Which of the following would best apply Newton's First Law to this
example.
The papers accelerated due to the force of the fan.
The papers are acted upon by an unbalanced force from the fan.
O The papers exerted an equal force on the air blown by the fan.
O The papers that were the heaviest were blown the closest.

Answers

Answer:

The second option - the papers are acted upon by an unbalanced force from the fan.

Explanation:

noooooooooooooooooooooooo

Answers

Answer:

yes

Explanation:

Answer:yeeeeeeeeeeeeeeeeeeeeeees

Explanation:

Match the measurements with the proper SI unit.

Acceleration:
A. Meters
B. Meters per second
C. Meters per second squared

Velocity:
A. Meters
B. Meters per second
C. Meters per second squared

Distance:
A. Meters
B. Meters per second
C. Meters per second squared

Answers

Explanation:

C. meter per second squared

B. meter per second

A. meter

Answer:

b. meters per second

c.meters per second squared

c.meters

Explanation:

ginawa ko na rin KC toh

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