HELP WITH SCIENCE STAAR QUESTIONS

Answer:

please give me brainlist and follow

Explanation:

Given:

The speed of the train ,which the boy is observing(t) = 18 km/hr

[ Now , to convert km/hr into m/s we have to multiply by 5/18 ]

So,

speed of the observed train = 18× 5/18

☞ 05 m/s

Also, The speed of the train in which the boy is sitting is(s) = 36 km/hr

Speed in m/s will be = 36 × 5/18

☞ 10 m/s

Also, The Length of the Train = 90m

Therefore:.

The speed of the train is given (expressed) by

= > speed \: = \frac{distance}{time}=>speed=

time

distance

= > time \: = \frac{distance}{Velocity }=>time=

Velocity

distance

Where,

velocity = Realtive velocity of both trains

Distance = Length of the train

So, The above mentioned formulae can also be written as :

= > time = \frac{length}{relative \: velocity}=>time=

relativevelocity

length

Here,

Relative velocity will be :

☞. s -(-t)

☞. 10 -(-5)

☞.15 m/s = Relative velocity

Now , Finally putting the values in the formulae respectively

■ Time = 90/15

■ Time = 6 sec [Answer]

Answer:

Acceleration = 2.8 m/s²

Explanation:

Given the following data;

Mass = 1500 kg

Net force = 4200 Newton

To find the truck's acceleration;

Newton's Second Law of Motion states that the acceleration of a physical object is directly proportional to the net force acting on the physical object and inversely proportional to its mass.

Mathematically, it is given by the formula;

[tex] Acceleration = \frac {Net \; force}{mass} [/tex]

Substituting into the formula, we have;

[tex] Acceleration = \frac {4200}{1500} [/tex]

Acceleration = 2.8 m/s²

Answer:

dorsiflexion

Explanation:

To decrease the angle between the anterior surface of the foot and anterior surface of the lower leg is described as: dorsiflexion

Answer:

dorsiflexion

Explanation:

Hope this helps

Answer:

13.78 mT

Explanation:

The peak voltage ε = ωNAB where ω = angular speed of coil = 1500 rpm = 1500 × 2π/60 rad/s = 50π rad/s = 157.08 rad/s, N = number of turns of coil = 250, A = area of coil = πr² where r = radius of coil = 10 cm = 0.10 m,

A = π(0.1 m)² = 0.03142 m² and B = magnetic field strength

So,

B = ε/ωNA  

substituting the values of the variables into the equation given that ε = 17 V

So, B = ε/ωNA

B = 17 V/(157.08 rad/s × 250 turns × 0.03142 m²)

B = 17 V/(1233.8634 rad-turns-m²/s)

B = 0.01378 T

B = 13.78 mT

Answer:

I think Albert Einstein invented physics.

Explanation:

Iam soory if Iam wrong.

Answer:

X = 50 g

Explanation:

Please see attached photo for explanation.

From the attached photo,

Anticlock–wise moment = X × 20

Clockwise moment = 100 × 10

Anticlock–wise moment = clockwise moment

X × 20 = 100 × 10

X × 20 = 1000

Divide both side by 20

X = 1000 / 20

X = 50 g

Therefore, the value of X is 50 g

Answer:

the  wavelength of the interfering waves for this mode is 2.4168

Explanation:

The computation of the wavelength of the interfering waves for this mode is shown below:

Given that

The length is 7.25m

And, the number of nodes is 6

So, the wavelength should be

= 2 × 7.25m ÷ 6

= 2.4168 m

Hence, the  wavelength of the interfering waves for this mode is 2.4168

The same would be considered

Answer:

True

Explanation:

Average speed is the rate at which an object is moving at a given instant in time.

Answer: false.

Explanation: i’m pretty sure that’s instantaneous speed.

Answer:

I study physics too, want me to study with you?

Answer:

1000 L= 1000 kg

1.000 L= 1.000 kg

Explanation:

It will be the same because L and kg have the same mass

Answer:

Potential energy only occurs when an object is in motion.

Explanation:

Energy can be defined as the ability (capacity) to do work. The two (2) main types of energy are;

a. Kinetic energy (K.E): it is an energy possessed by an object or body due to its motion.

Mathematically, kinetic energy is given by the formula;

[tex] K.E = \frac{1}{2}MV^{2}[/tex]

Where;

K.E represents kinetic energy measured in Joules.

M represents mass measured in kilograms.

V represents velocity measured in metres per seconds square.

b. Potential energy (P.E): it is an energy possessed by an object or body due to its position above the earth.

Mathematically, potential energy is given by the formula;

[tex] P.E = mgh[/tex]

Where,

P.E represents potential energy measured in Joules.

m represents the mass of an object.

g represents acceleration due to gravity measured in meters per seconds square.

h represents the height measured in meters.

Additionally, the mechanical energy of a physical object or body is the sum of the potential energy and kinetic energy possessed by the object or body.

Mathematically, it is given by the formula;

Mechanical energy = P.E + K.E

Answer:

V2 = 37.5 L

Explanation:

Given the following data;

Initial volume, V1 = 25 L

Initial temperature, T1 = 20°C

Final temperature,T2 = 30°C

To find the final volume V2, we would use Charles' law;

Charles states that when the pressure of an ideal gas is kept constant, the volume of the gas is directly proportional to the absolute temperature of the gas.

Mathematically, Charles is given by;

[tex] \frac {V}{T} = K[/tex]

[tex] \frac{V_{1}}{T_{1}} = \frac{V_{2}}{T_{2}} [/tex]

Making V2 as the subject formula, we have;

[tex] V_{2}= \frac{V_{1}}{T_{1}} * T_{2}[/tex]

[tex] V_{2}= \frac{25}{20} * 30 [/tex]

[tex] V_{2}= 1.25 * 30 [/tex]

V2 = 37.5 L

Explanation is[tex]^{}[/tex] in a file

bit.[tex]^{}[/tex]ly/3tZxaCQ

Answer:

271.095 m

Explanation:

✓ Let speed of sound in air that was given as (343 m/s) be represented as (Vi)

✓( speed of sound in concrete that was given as (3000 m/s ) be debited as (Vc)

✓ Let the distance travelled by the sound = s

✓duration of Time that exist between heard of sounds = 0.70s

But we know that

Time = (Distance / Speed)

✓Time it takes the sound to travel through air= s/vi = s/343

✓Time it takes the sound to travel through concrete= s/vc = s/3000

✓ (s/343) - (s/3000) = 0.70

Finding LCM and simplify

[(3000s - 343s)]/1029000 = 0.70

2657s /1029000 = 0.70

Making " s" subject of the formula

s= (1029000 × 0.70)/2657

s=720300/ 2657

s= 271.095 m

Hence, The impact took place at a distance of 271.095 m away from the person.

Answer:

Teaching is the process of attending to people's needs, experiences and feelings, and making specific interventions to help them learn particular things.

Explanation:

Answer:

In education, teaching is the concerted sharing of knowledge and experience, which is usually organized within a discipline and, more generally, the provision of stimulus to the psychological and intellectual growth of a person by another person or artifact.

Answer:

The frequency increases by a factor of 3.

Explanation:

The relation between speed, wavelength and frequency of a wave is given by :

[tex]v=f\lambda[/tex]

or

[tex]f\propto \dfrac{1}{\lambda}[/tex]

A wave travels at a constant speed. If the wavelength is reduced by a factor of 3, it would mean that the frequency increases by a factor of 3 because there is an inverse relationship between wavelength and frequency.

Answer:

Wavelength = 1.36 * 10^{-34} meters

Explanation:

Given the following data;

Mass = 0.113 kg

Velocity = 43 m/s

To find the wavelength, we would use the De Broglie's wave equation.

Mathematically, it is given by the formula;

[tex] Wavelength = \frac {h}{mv} [/tex]

Where;

h represents Planck’s constant.

m represents the mass of the particle.

v represents the velocity of the particle.

We know that Planck’s constant = 6.6262 * 10^{-34} Js

Substituting into the formula, we have;

[tex] Wavelength = \frac {6.6262 * 10^{-34}}{0.113*43} [/tex]

[tex] Wavelength = \frac {6.6262 * 10^{-34}}{4.859} [/tex]

Wavelength = 1.36 * 10^{-34} meters

Answer:

1

Explanation:

Answer:

It is a form of mechanical energy

Explanation:

Answer:

medium

Explanation:

I am not really sure

Answer:

It's important

Explanation:

Mental wellness is critical to overall physical health. Participating in recreational activities helps manage stress. Taking time to nurture oneself provides a sense of balance and self-esteem, which can directly reduce anxiety and depression.

Answer:

Mental wellness is critical to overall physical health. Participating in recreational activities helps manage stress. Taking time to nurture oneself provides a sense of balance and self-esteem, which can directly reduce anxiety and depression.

Explanation:

Answer:

1. G.P.E = 24 J

2. center of mass

Explanation:

Given the following data;

Mass = 2kg

Height, h = 1.2m

Acceleration due to gravity = 9.8 N/kg or m/s².

To find the gravitational potential energy;

Gravitational potential energy (GPE) is an energy possessed by an object or body due to its position above the earth.

Mathematically, gravitational potential energy is given by the formula;

[tex] G.P.E = mgh[/tex]

Where;

Substituting into the formula, we have;

[tex] G.P.E = 2*1.2*9.8 [/tex]

G.P.E = 23.52 to 2 S.F = 24 Joules.

Translation kinetic energy is defined as the energy of a system due to the motion of the system’s center of mass. The center of mass is typically where the mass of the object or particle is concentrated.

Answer:30watt

Explanation:  Force applied by student F = 12 N

Displacement s = 10 m

Time t = 4 s

Work done W = Fs

Power P = W/t = Fs/t

= 12 * 10/4 Watt

= 30 Watt

The power developed by the student is 30 Watt.

To find the value of power the given values are,

Force applied by the student F = 12 Newton,

Distance s = 10 meters,

Weight pulled by the students = 50 Newton,

Time t = 4 seconds.

Work done:

  The product of displacement of an object and the component of the applied force which is in the direction of the object's displacement is said to be Work done.

      It's unit is kg⋅m²⋅s⁻² or Joules.

  Work done W = Force ( F ) × Distance ( S )

                          = 12 × 10

                          = 120 J.

Power:

  Power can be defined as the ratio of work done to time interval.

                 [tex]P = \frac{W}{\Delta t}[/tex]

 It's unit is Watt.

  Power , P = 120 / 4

                P = 30 Watt.

Thus, the power developed by the student is 30 watt.

Learn more about Power,

https://brainly.com/question/1962126

#SPJ2

[tex]\bcancel{\huge\red{\fbox{\tt{࿐αɴѕωєя࿐}}}}[/tex]

Force is defined as the rate of change of momentum. For an unchanging mass, this is equivalent to mass x acceleration. So, 1 N = 1 kg m s-2, or 1 kg m/s2.

Answer:

it's the second one;

if the frequency increases, wavelength decreases

Explanation:

we know, v=f×lamda(wave length)

so for constant velocity Frequency f is inversely proportional to lamda

i.e.

fα 1/lamda

so as the f increases lamda decreases and vise versa

A true relationship between the various wave components is if frequency increases, wavelength decreases.

The frequency is the reciprocal of the time period of the wave.

The wavelength is the distance between the two adjacent crest of the wave.

If the wavelength decreases, the number of cycles will increase in a certain time.

Hence, a true relationship between the wave components is if frequency increases, wavelength decreases.

Learn more about Frequency.

https://brainly.com/question/5102661

#SPJ2

Explanation:

a hot toothbrush. ......lol

Answer:

351.28 N

Explanation:

Let F be the force on the object and f be the frictional force. The component of the force acting in the horizontal direction causing the object to move is FcosФ where Ф is the angle between F and the horizontal = 43.0°. The frictional force on the packing crate f = μN where μ = coefficient of kinetic friction = 0.35 and N = normal force = W = weight of the packing crate = mg where m = mass of crate = 74.9 kg and g = acceleration due to gravity = 9.8 m/s².  So, f = μN = μW = μmg

So, the net force on the packing crate is

FcosФ - f = ma

FcosФ - μmg = ma

Since the crate moves at constant speed, its acceleration a = 0

So, FcosФ - μmg = ma

FcosФ - μmg = m(0)

FcosФ - μmg = 0

FcosФ = μmg

F = μmg/cosФ

Substituting the values of the variables into the equation, we have

F = μmg/cosФ

F = 0.35 × 74.9 kg × 9.8 m/s²/cos43.0°

F = 256.907 kg-m/s²/0.73135

F = 351.28 kg-m/s²

F = 351.28 N