can anyone heelp me pls

Answer:

Electrostatic phenomenon is a from the forces that electric charges exert on each other.

The Two examples of contact forces are:

The two examples of non contact forces are:

Contact forces happens due to the contact between two objects

Non Contact forces happens because there is no contact between two objects. There is no attraction.

Answer:

= 3.87 m/s

Explanation:

Since momentum is conserved, momentum right before and after the boy jumps onto the skateboard should be the same.

Initial momentum = momentum of boy = 43.2 x 4.10 = 177 kg·m/s

Final momentum = momentum of boy and skateboard = (43.2 + 2.50) x v = 45.7v

177 = 45.7v

v = 177 / 45.7 = 3.87 m/s

(Hope this helps can I pls have brainlist (crown)☺️)

The combined velocity of the boy and the skateboard just after the boy lands on it will be equal to 3.87 m/s.

Momentum is the product of a particle's mass and velocity. Being a vector quantity, momentum possesses both direction and magnitude. According to Isaac Newton's second equation of motion, the force applied on a particle is equivalent to the temporal rate at which momentum changes. 

According to Newton's second law, the product of the energy and the time interval is equal to the shift in momentum if a constant force acts on a molecule for a specified amount of time.

Momentum should be the same both before and after the boy gets onto the skateboard because it is preserved.

Initial momentum = momentum of boy

= 43.2 × 4.10 = 177 kg m/s

Final momentum = momentum of boy as well as skateboard

= (43.2 + 2.50) × v = 45.7 v

177 = 45.7 v

v = 177 / 45.7 = 3.87 m/s

Therefore, the combined velocity of boy and skateboard is 3.87 m/s.

To know more about momentum :

https://brainly.com/question/24030570

#SPJ2

Answer/Explanation:

True

A fixed pulley changes the direction of the force you exert by pulling, so you can pull down to move an object up. In this fixed pulley system, you pull down on one side of the rope and the other side goes up. You use the same amount of force to pull down as you would to lift the toy yourself.

Explanation:

Let's calculate the components of the football's velocity:

[tex]v_{0x} = (23.9\:\text{m/s})\cos{51.5°} = 14.9\:\text{m/s}[/tex]

[tex]v_{0y} = (23.9\:\text{m/s})\sin{51.5°} = 18.7\:\text{m/s}[/tex]

a) The time it takes for the football to travel 36.0 m horizontally is

[tex]t = \dfrac{x}{v_{0x}} = \dfrac{36.0\:\text{m}}{14.9\:\text{m/s}} = 2.4\:\text{s}[/tex]

During this time, the y-displacement of the football is

[tex]y = v_{0x}t - \frac{1}{2}gt^2[/tex]

[tex]\:\:\:\:= (18.7\:\text{m/s})(2.4\:\text{s}) - \frac{1}{2}(9.8\:\text{m/s}^2)(2.4\:\text{s})^2[/tex]

[tex]\:\:\:\:= 16.7\:\text{m}[/tex]

This means that the football cleared the crossbar by 16.7 m - 3.05 m = 13.7 m

b) To determine whether the football was rising or falling while clearing the crossbar, let's look at the y-component of its velocity after 2.4 s:

[tex]v_y = v_{0y} - gt = 18.7\:\text{m/s} - (9.8\:\text{m/s}^2)(2.4\:\text{s})[/tex]

[tex]\:\:\:\:\:\:= -4.82\:\text{s}[/tex]

Since its sign is negative, this means that the football was already on its way down.

(C)

...........................

Answer:

Hope this helps!

Explanation:

Answer: Yes Because it matches with the mass and the amount of force Hope this helps :>

Explanation:

Answer:

(neutral)

(protons)

(electrons)

Explanation:

Electrons have a negative charge (-) while protons have a positive (+) charge.

Atoms will usually be neutral, which means that there will be no charge.

For an atom to have a neutral charge, protons and electrons must "cancel" each other out. For this to happen, you need to have the same amount of each.

Positive will "cancel" out the negative.

Explanation:

The final velocity at the cannon ball's maximum height is zero ([tex]v_y = 0[/tex]). We can use the equation

[tex]v_y^2 = 0 = v_{0y}^2 - 2gy_{max}[/tex]

[tex]\Rightarrow y_{max} = \dfrac{v_{0y}^2}{2g}[/tex]

[tex]y_{max} = \dfrac{(25\:\text{m/s})^2}{2(9.8\:\text{m/s}^2)}[/tex]

[tex]\:\:\:\:\:\:\:=31.9\:\text{m}[/tex]

Answer:

Atoms.

Explanation:

The fundamental structure obstructs that make matter are called molecules. What are the various particles found in iotas? (Reply: electrons, protons and neutrons) Where are they found? (Reply: Protons and neutrons are found in the core, and electrons are found in shells around the outside of the core.)

Really hope this helps! :D

Explanation:

The basic components of matter are called atoms. What are the various particles present in an atom?

(Answer: electrons, protons, neutrons) Where are they? (Answer: Protons and neutrons are in the nucleus, and electrons are in the shell around the nucleus.)

Explanation:

M.A = load / Effort

efficiency = M.A/V.R X 100

75 = M.A / 4 X 100

75 = 25 X M.A

M.A = 75/25 = 3

M.A = load / effort

3 = 100/E

E = 100/3 = 33.333

A machine whose efficiency is 75% is used to lift a load of 100m. the effort needed to put into the machine is 33.33 meters if the velocity ratio is 4.

Mechanical advantage is defined as a measure of the ratio of output force to input force in a system, It is used to analyze the forces in simple machines like levers and pulleys.

Mechanical advantage = output force(load) /input force (effort)

Simple machines like static pulleys, as well as a movable pulleys, provide a great amount of mechanical advantage.

A machine whose efficiency is 75% is used to lift a load of 100m.calc if it has a velocity ratio of 4.

As we know that the mechanical advantage of a machine is equal to the product of its efficiency and velocity ratio.

mechanical advantage  = velocity ratio   ×Efficiency

       =4 × 0.75

       = 3

The mechanical advantage is 3 , which means the ratio of load to effort is 3

load / effort = 3

100 m/effort =3

effort = 33.33 m

Thus, the effort put into the machine comes out to be 33.33 m.

Learn more about Mechanical advantages, here

https://brainly.com/question/16617083

#SPJ5

This question involves the concepts of the rectangular components of the vector and the resultant of the vectors.

The magnitude of the resultant force is "72.11 N", and it makes an angle of "33.7°" from one of the vectors.

The rectangular components of a vector are those components that have a right angle between them. The resultant of two rectangular components of a vector can be found using the following formula:

[tex]F = \sqrt{F_1^2+F_2^2}[/tex]

where,

F = resultant force = ?

F₁ = First component of force = 40 N

F₂ = Second component of force = 60 N

Correction: The unit in question is given as m/s, while the unit of force is N. Hence, N is taken here.

Therefore,

[tex]F = \sqrt{(40\ N)^2+(60\ N)^2}[/tex]

F = 72.11 N

The following formula can be used to find the angle of resultant from 60N vector:

[tex]\theta = tan^{-1}(\frac{40\ N}{60\ N})\\\\[/tex]

θ = 33.7°

Learn more about rectangular components of a vector here:

https://brainly.com/question/14793638?referrer=searchResults

The attached picture shows the resultant calculation for the rectangular components of a vector.

Answer: These apparent star tracks are in fact not due to the stars moving, but to the rotational motion of the Earth. As the Earth rotates with an axis that is pointed in the direction of the North Star, stars appear to move from east to west in the sky.

Explanation: why do the star constellations seem to move across the sky

Answer:

because the world moves around and around rotating in a circle and circling around the sun so as we move the stars stay the same but to our view it looks like their moving but in reality we are.

Explanation:

Answer:

include the statements pls so i can choose wich one it is and tell you

Explanation:

Answer:

s times t

Explanation:

The equation for distance is D = st

Answer:

D is the correct answer (D=S*T)

This is an algebraic law; if you are to move the denominator or numerator to the other side of the equation, you must multiply it by the other side.

S=D/T is the same as D=S*T.

so distance=speed times time.

so if you are going 50 miles per hour, you multiply that times time, say one hour. you get your D distance which is 50 miles.

Conociendo la longitud y frecuencia de un péndulo, queremos encontrar la longitud de otro pendulo de tal forma que tenga otra frecuencia.

Veremos que la longitud del nuevo péndulo debe ser 6.25m

Sabemos que un péndulo de 4m de longitud tiene una frecuencia de 5Hz.

La frecuencia de un péndulo está dada por:

[tex]f = \frac{1}{2*\pi} *\frac{g}{l}[/tex]

Donde g es la aceleración gravitatoria y l es la longitud del péndulo, remplazando los datos que tenemos en esa ecuación obtenemos:

[tex]5 Hz = \frac{1}{2*3.14} *\sqrt{\frac{g}{4m} } \\\\(5Hz*2*3.14)^2*4m = g = 3,943.8 m/s^2[/tex]

Ahora debemos encontra la longitud de tal forma que la frecuencia sea 4Hz, entonces debemos resolver:

[tex]4Hz = \frac{1}{2*3.14} *\sqrt{ \frac{3943.8m/s^2}{l} }\\\\4hz*2*3.14 = \sqrt{ \frac{3943.8m/s^2}{l} }\\\\l =\frac{3943.8m/s^2}{ (4hz*2*3.14)^2} = 6.25m[/tex]

La longitud del nuevo péndulo deve ser 6.25m

Sí quieres aprender más, puedes leer:

https://brainly.com/question/23483504

Answer:

there are 1,000m in a km, so 200km is 200,000m

200,000m/10m/s = 20,000s

Explanation:

Please mark me Brainlyest

Answer:

Explanation:

a) A is accurate because the half of the Moon that is facing the sun is it by the sun, and the other half is dark.

The most accurate diagram of the Sun and Moon is: a. A is accurate because the half of the Moon that is facing the sun is it by the sun, and the other half is dark.

A Moon can be defined as the natural satellite of planet Earth that shines due to the Sun's reflected light (sunlight), as it revolves around the Earth from west to east in 29½ days.

Based on astronomical information, there are four (4) primary Moon phases and these are:

In conclusion, diagram A is the most accurate because half of the Moon that faced the Sun is lit by the Sun while the other half is dark.

Read more on Moon here: brainly.com/question/1286910

Answer:an iron-nickel alloy or nickel -iron alloy abbreviated FeNi or NiFe is a group of alloys consisting primarliy of the elemtns nickel and iron.

Explanation:

Answer:

Iron and nikel are example of "Metal" materials.

The S.I unit of solid angle is steradian, or square radian (symbol: sr).

The mass of the object experimented in the situation will be equal to 20 kg in each case. Hence, option C is correct.

Acceleration is the rate at which the speed and orientation of a moving object change over time. When a spot or object moves faster or slower along a straight line, it is said to be accelerated. Even though the speed is constant, motion on a circle accelerates so because the direction is always shifting. Both by and to acceleration for all other types of motion.

It is a vector quantity because it has both magnitude and direction.

The given data as per the question is,

Force, F = 30 N

Acceleration, a = 1.5 m/s²

[tex]Force = mass*acceleration[/tex]

30 N = m × 1.5

m = 30/1.5

m = 20 kg.

Therefore, the mass of the object is 20 kg.

To know more about acceleration:

https://brainly.com/question/12550364

#SPJ2

Answer:

Explanation:

It's a velocity•time chart. As distance = vt, the area under the curve between limits is the distance traveled.

Pic is fuzzy so I will ASSUME the horizontal axis is seconds and vertical is meters per second.

0 s ≤ t ≤ 5 s = ½(5 - 0)(30 - 0) = 75 m

5 s ≤ t ≤ 10 s = (10 - 5)(30 - 0) = 150 m

10 s ≤ t ≤ 15 s = ½(30 + 20)(15 - 10) = 75 m

0 s ≤ t ≤ 25 s = 75 + 150 + 75 + 20(20 - 15) + ½(20)(25 - 20) = 450 m

Answer:

correct answer is A) the height of a wave

Explanation:

i just did the test:)

The amplitude is used represent the height of the wave.

A wave is a disturbance in a medium that carries energy without a net movement of particles. In general, waves are classified into two types as Longitudinal and Transverse

Given is the amplitude of a wave.

Amplitude of a wave is equal to measure of the length of crest or trough. Crest and trough are the points that represents the maximum and minimum displacement of the wave with respect to the reference axis. The crest and the trough points are both at a equal straight line distance from the reference axis. This distance is also called height of the wave. The amplitude is the distance between the centerline and the Crest or trough. The general equation representing the amplitude of wave is x = A sin (ωt + ϕ) or x = A cos (ωt + ϕ) is the formula.

Therefore, the amplitude represents the height of the wave.

To solve more questions on Amplitude, visit the link below-

https://brainly.com/question/17003906

#SPJ2

Answer:

[tex]-1.99\:\mathrm{m/s}[/tex]

Explanation:

Assuming that the equation is intended to be [tex]\displaystyle x=\cos\left(\frac{2\pi}{3}t\right)[/tex], we can find the velocity vs. time equation by taking the first derivative with respect to [tex]t[/tex]:

[tex]\displaystyle \frac{dx}{dt}=\frac{d}{dt}\left(\cos\left(\frac{2\pi}{3}t\right)\right)[/tex]

Recall the chain rule:

[tex]\displaystyle f(g(x))'=f'(g(x))\cdot g'(x)[/tex]

Therefore,

[tex]\displaystyle \frac{d}{dt}\left(\cos\left(\frac{2\pi}{3}t\right)\right)=-\sin\left(\frac{2\pi}{3}t\right)\cdot \frac{2\pi}{3}[/tex]

Therefore, the velocity vs. time equation of the object is [tex]\displaystyle v=-\sin\left(\frac{2\pi}{3}t\right)\cdot \frac{2\pi}{3}[/tex].

Substitute [tex]t=0.6\text{ s}[/tex] into this equation to find the velocity at that given time:

[tex]\displaystyle v=-\sin\left(\frac{2\pi}{3}(0.6)\right)\cdot \frac{2\pi}{3}\approx \boxed{-1.99\text{ m/s}}[/tex]

Answer:  

1N  

Explanation:

Pretty simple Divide 23 by 23 which gives you 1.

23N ÷ 23N = 1N

Answer:

[tex]\sf \longmapsto \: 1 \: N[/tex]

Explanation:

[tex]\sf \longmapsto \frac{23N}{23N} [/tex]

[tex]\sf \longmapsto1 \: N[/tex]

Answer:

D) 19.8 lbs

Explanation:

1kg in household measurement is equal to 35.274 ounces. 35.274*9=317.466 ounces.

1kg is also equal to 2.205 lbs. 9*2.205=19.8416

9 kg is also equal to 9000 grams, but grams are not a part of the household measurement system

a) 9000 grams. b) 9000 ounces. c) 19.8 ounces. d) 19.8 pounds.

This leaves us with 19.8 lbs