1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
OLga [1]
3 years ago
10

A player kicks a football (from the ground) at an initial angle of 30°. The football is in the air for 2.4 s before it hits an o

pposing player. The opposing player was a horizontal distance x = 50 m away from where the football was kicked. What was the initial horizontal velocity component of the football?

Physics
1 answer:
wolverine [178]3 years ago
8 0

Answer:

The initial horizontal velocity was 21 m/s

Explanation:

Please, see the figure for a better understanding of the problem.

The equation for the position of an object moving in a parabolic trajectory is as follows:

r = (x0 + v0 · t · cos α, y0 + v0 · t · sin α + 1/2 · g ·t²)

Where:

r = vector position at time t

x0 = initial horizontal position

v0 = initial velocity

t = time

α = launching angle

y0 = initial vertical position

g = acceleration due to gravity

Notice that at time t = 2.4 s the vector "r" is the one in the figure. We know that the x-component of that vector is 50 m. Then using the equation for the x-component of the vector "r", we can calculate the initial velocity:

x = x0 + v0 · t · cos α

Let´s place the center of the frame of reference at the point of the kick so that x0 = 0.

x =  v0 · t · cos α

x/t = v0 · cos α

Notice in the figure that v0 · cos 30° = v0x which is the initial horizontal velocity. Remember trigonometry of right triangles:

cos α = adjacent / hypotenuse = v0x / v0

Then:

50 m/ 2.4 s = v0 · cos 30° = v0x

v0x = 21 m/s

You might be interested in
Wel.
Law Incorporation [45]

Answer:

1 is c 2 is a and 3 is b hope that helped!

4 0
3 years ago
Which is an example of sliding friction?
Anvisha [2.4K]
I think its D not sure
4 0
3 years ago
Read 2 more answers
How do I calculate the efficiency of motor
zepelin [54]

Answer:

the formula is efficiency = output / input × 100%

7 0
3 years ago
A yellow train of mass 100 kg is moving at 8 m/s toward an orange train of mass 200 kg traveling in the opposite direction on th
Serhud [2]

The initial momentum of the yellow and the orange train is 1000kgm/s.

Momentum is the product of the mass and velocity of any object.

Momentum is denoted by P.

Momentum P = mv , where m = mass and v = velocity.

<h3>Given:</h3>

Mass of the orange train = 200kg

Velocity of the orange train = 1m/s

So, the momentum of the orange train will be,

                            ∴    P = mv

                                  P = 200 x 1

                                  P = 200 kgm/s

∴   The initial momentum of the orange train is 200kgm/s.

Mass of the yellow train = 100kg

Velocity of the yellow train = 8m/s

So, the momentum of the yellow train will be,

                            ∴    P = mv

                                  P = 100 x 8

                                  P = 800 kgm/s

∴ The initial momentum of the yellow train is 800kgm/s.

Therefore, the initial momentum of the yellow and the orange train is 1000kgm/s.

Learn more about momentum here:

brainly.com/question/25849204

#SPJ1

5 0
2 years ago
Lunar missions have revealed that the moon has:
myrzilka [38]
That the moon has soil within its shadowy craters rich and useful material
5 0
3 years ago
Other questions:
  • If your mass is 100 kg on earth, what do you weigh on the moon?
    11·2 answers
  • Matter is lost when a candle is<br> burned.<br> True or False?
    8·2 answers
  • PLEASE HELP!! PHYSICS QUESTION-DOES ANYONE KNOW HOW TO DO THIS WITH THE WORKING OUT?!?
    14·1 answer
  • A capacitor is connected to a power source and begins charging. What causes the capacitor to stop charging while it is still con
    10·1 answer
  • Need help before 10pm tomorrow night
    8·1 answer
  • A student throws a rock horizontally off a 5.0 m tall building. The rock's initial speed is 6.0 m/s. How long will it take the r
    8·2 answers
  • You are standing on a sheet of ice that covers the football stadium parking lot in Buffalo; there is negligible friction between
    6·1 answer
  • 3<br> Select the correct answer.<br> What is a substance?
    11·1 answer
  • What do all the items that light up a bulb have in common? (help)
    6·1 answer
  • What is the primary way the metamorphic rock formed
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!