Can you fill in the blanks for me

a football is kicked toward a goal keeper with an initial speed of 20m/s at an angle of 45 degrees with the horizontal .at the m

algol [13]

Answer:

3.18 m/s

Explanation:

Given that

Initial speed of the ball, u = 20 m/s

Angle of inclination, θ = 45°

Distance from the ball, h = 50 m

Using equations of projectile to solve this, we have

We start by finding the time of flight, T

T = 2Usinθ/g

T = (2 * 20 * sin45)/9.8

T = (40 * 0.7071) / 9.8

T = 28.284/9.8

T = 2.89 s

Next we find the Range, R

R = u²sin2θ/g

R = (20² * sin 90) / 9.8

R = (400 * 1) / 9.8

R = 400/9.8 = 40.82 m

Distance the gk must cover

40.82 - 50 m

-9.18 m or 9.18 m in the opposite direction.

Speed of the GK = d/t

9.18 / 2.89 = 3.18 m/s

5 0

4 years ago

A 1.20x10^3 kilogram car is traveling east at 25 meters per second. the brakes are applied and the car is brought to rest in 5.0

lana [24]

Answer:

F = 7500 N

Explanation:

given,

mass of the car, m = 1200 Kg

initial speed of the car, v = 25 m/s

final speed of car = 0 m/s

time in which car is at rest, t = 5 s

distance = 50 m

Force = ?

using equation of motion for the calculation of acceleration.

v² = u² + 2 a s

0² = 25² + 2 x a x 50

100 a = -625

a = - 6.25 m/s²

negative sign shows deceleration of the car

now, force calculation

F = m a

F = 1200 x 6.25

F = 7500 N

hence, net force is equal to F = 7500 N

5 0

3 years ago

The direction of electrical force is based on the fact that like charges will

tigry1 [53]

yes

Explanation:

because hindi ko tlaga ala

6 1

3 years ago

A photon has momentum of magnitude 8.30×10−28 kg⋅m/s . Part APart complete What is the energy of this photon? Give your answer i

d1i1m1o1n [39]

Answer with Explanation:

We are given that

Momentum of photon= $8.3\times 10^{-28} kg.m/s$

a. We have to find the energy of this photon.

Speed of photon= $c=3\times 10^8 m/s$

We know that

Momentum=p= $\frac{h}{\lambda}$

Where

h= $6.63\times 10^{-34}$ J-s=Plank's constant

$\lambda=$ Wavelength of photon

$\lambda=\frac{h}{p}$

$\lambda=\frac{6.63\times 10^{-34}}{8.3\times 10^{-28}}$

$\lambda=7.99\times 10^{-7}$ m

$E=\frac{hc}{\lambda}$

$E=\frac{6.63\times 10^{-34}\times 3\times 10^8}{7.99\times 10^{-7}}$

$E=2.49\times 10^{-19}$ J

Hence, the energy of photon= $2.49\times 10^{-19}$ J

B.Energy of photon in electron volt= $\frac{2.49\times 10^{-19}}{1.6\times 10^{-19}}=1.55 eV$

Energy of photon= $1.55eV$

C.Wavelength of photon = $\lambda=7.99\times 10^{-7}m$

6 0

4 years ago

A person stands between two speakers driven by the same source. Each speaker produces a tone with a frequency of 200 Hz on a day

MissTica

Answer:

The type of interference the person perceives is a Constructive Interference

Explanation:

Before we solve the problem we need to clarify some concepts:

There are two types of Interference, the Constructive and the Destructive interference

The Constructive Interference happens if the difference between the waves movement is equal to an even semi-wavelength number

The Destructive Interference is the opposite than the Constructive Interference, it happens if the difference between the waves movement is equal to an odd semi-wavelength number

Taking the above into account let´s proceed to solve the problem.

First, we will need to find how much the wavelength is (we will call it l), we know the frequency f=200Hz, we also know the speed of sound is v=330m/s. We will use the next equation:

$l=v/f$ then we get that $l=1.65m$

In order to find the semi-wavelength we must divide by 2 the previous result, in this case the semi-wavelength will be:

$l/2=0.825m$

Now, we find the difference between the waves movement, which is the difference between both distances, this difference will be called d and we will find it this way:

$d=4.95m-1.65m$ then d=3.3m

After this, we will do a relation between the distance and the semi-wavelength in order to find what type of interference the person perceives, this way:

$(d)/(l/2)$ then, we have a relation equals to 4. As it´s an even number, we determine the interference is a Constructive Interference

8 0

4 years ago