Please help me with this!!!​

Answer:

Explanation:

As the ball rises, its PE increases because the potential energy is equal to the mass of the ball times gravity times the height of the ball. The higher the height, the higher the PE.

Answer:

According to the law of conservation of energy its kinetic energy is getting converted in to potential energy because of gain in height. So, if the velocity of a ball goes on decreasing when it is thrown vertically upwards. When its velocity becomes zero, its potential energy becomes maximum.

Answer:

A

Explanation:

We know that impulse(J) is the force times the change in time OR mass times the change in velocity. Because we're given mass and a final and initial velocity, we'll use the second option written as:

mΔv=J

Since Δ means change in, and Δv= vf-vi, we subtract 10 m/s from 15 m/s to get 5 m/s for Δv.  

Now plugging in Δv and m(1,200 kg)

1,200 kg * 5 m/s =J

6000 kg* m/s = J

Answer:

Our weight on moon is less than it would be on Earth.

Explanation:

Due to a difference of the strength of gravity on the moon. The moon's gravitation force is determined by the mass and the size of the moon. Since the moon has significantly less mass than the Earth, it will not pull objects toward itself at the strength that Earth will. This means that if you went to the moon you would weigh less, even though your mass stays the same.

Answer:

I = 0.2 A

Explanation:

Lamp is rated at 300 mA

I_lamp = 0.3 A

Voltage is; V = 3V

Thus; Resistance is given by;

R = V/I

R = 3/0.3

R = 10 ohms

Now, since the ammeter of 5 ohms is connected in series with the lamp. Thus equivalent resistance;

R_eq = 10 + 5

R_eq = 15 ohms

Ammeter current will be;

I = V/R_eq

I = 3/15

I = 0.2 A

Explanation:

average speed is the total distance divided by total time

Answer:

A

Explanation:

EDGE22

Explanation:

The inertia of a 4 kg mass is four times as great as a 1 kg mass.

Answer:

ME= 196.2 J

KE= 136.2

Explanation:

potential energy=mgh 2*9.81*10

Our ME is quivalent to PE as that is the toal amount of energy in the system

Kinetic energy= 1/2 m[tex]v^{2}[/tex]

to solve for kinetic enrgy we need to use a kinaetmtic equation that help us find velocity

vf= vi+at

but we need to find time first

d=vi+1/2(accelretaion)[tex]t^{2}[/tex]

7=0+1/2(9.81)[tex]t^{2}[/tex]

t= 1.19 s

vf= 0+ 9.81*1.19

vf= 11.67 m/s

Now

1/2 m[tex]v^{2}[/tex]

1/2*2*[tex]11.67^{2}[/tex]

= 136. 2

or we could just (PE/10)*7

so (196.2/10)*7

it will hit the ground maybe in like 1 second I guess

Answer:

n sei

Explanation:

n seei

Answer:

i relly need help with points it  whould help if you make me brainliest

Explanation:

Answer:

[tex]W=7.56\times 10^{-19}\ J[/tex]

Explanation:

Given that,

The work function for silver is 4.73 eV.

We need to find the value of the work function from electron volts to joules.

We know that,

[tex]1\ eV=1.6\times 10^{-19}\ J[/tex]

For 4.73 eV,

[tex]4.73\ eV=1.6\times 10^{-19}\times 4.73\\\\=7.56\times 10^{-19}\ J[/tex]

So, the work function for silver is [tex]7.56\times 10^{-19}\ J[/tex].

Every living things gives off thermal energy in the form electromagnetic waves. The electromagnetic wave releasing off is  infrared radiation. Hence, option C is correct.  .

Electromagnetic waves are associated with a combined electric field and magnetic field. They can pass through vacuum as well as through a medium. Unlike mechanical waves, all the electromagnetic waves are transverse waves.

The oscillation of particles is in the direction perpendicular to the wave propagation. There are 7 types of  radiations in the electromagnetic spectrum. The light we see is called visible light.

The infrared waves are located in between microwaves and visible light. Every  living thing gives off thermal energy in the form of infrared radiation. Hence, option C is correct.

Find more on infrared waves:

https://brainly.com/question/30309627

#SPJ2

Answer:

The Sun on Mars appears two third of the size of the Sun as seen Earth

Explanation:

The distance from the Sun to Mars = 1.5 × The distance from the Sun to Earth

Therefore, compared to the Sun as seen on Earth, we have;

The Sun as seen on Mars = 1.5 × smaller than the Sun as seen on Earth = 2/3 × The size of the Sun as seen on Earth

Answer:

Explanation:

This is a First Law of thermodynamics problem. We have to remember that the total energy available to a system is constant throughout the whole problem and that energy cannot be created or destroyed. So we need to find the total energy available right at the start. Well it just so happens that we are told that the total energy is 1000J and that it is all potential energy when the sphere is at rest and is 25 m off the ground. If the object isn't moving, all the energy is potential until it starts moving and the energy begins to convert from potential to kinetic a little bit at a time. The thing that we don't know is the mass of the shpere. Begin with the fact that the PE = 1000 (I'm going to se 2 sig fig's since there's only 1 in 1000). If

PE = 1000 and PE = mgh, then

1000 = m(9.8)(25) so

m = 4.1 kg

We also need the height at which this sphere has a PE of 600. Again, if

PE = 600 and PE = mgh, then

600 = (4.1)(9.8)h so

h = 15 Filling in the total energy equation now, using the fact that the total energy available to the system is 1000J:

TE = PE + KE and

1000 = (4.1)(9.8)(15) + [tex]\frac{1}{2}(4.1)v^2[/tex] and we are looking for v.

1000 = 6.0 × 10² + 2.1v² so

[tex]v=\sqrt{\frac{1000-6.0*10^2}{2.1} }[/tex] and

[tex]v=\sqrt{\frac{4.0*10^2}{2.1} }[/tex] gives us

v = 14 m/s

Answer:

The impulse received by the ball is - 1.561 kg.m/s

Explanation:

Given;

mass of the ball, m = 0.175 kg

initial displacement of the ball, h₁ = 1.25 m

final displacement of the ball, h₂ = 0.805 m

Assumptions:

let the downward direction of the ball be positive

let the upward direction of the ball be negative

The following equation of motion will be used to determine the final velocity of the ball at each displacement.

v² = u² ± 2gh

The final velocity of the ball when it is dropped downwards to 1.25 m;

v² = u² + 2gh

v² = 0 + 2gh

v² = 2gh

v = √2gh

v = √(2 x 9.8 x 1.25)

v = 4.95 m/s

The final velocity of the ball when it rebounds from the floor to 0.805 m;

vf² = u² - 2gh

vf² = 0² - 2gh

vf² =  -2gh

vf = -√2gh

vf = - √(2 x 9.8 x 0.805)

vf = -3.97 m/s

The impulse received by the ball is calculated as;

J = ΔP = mΔv = m(vf - v)

                      = 0.175(-3.97 - 4.95)

                       = - 1.561 kg.m/s

The negative sign indicates upward direction of the impulse.

Answer:

the tension of the rope is 34.95 N

Explanation:

Given;

length of the rope, L = 3 m

mass of the rope, m = 0.105 kg

frequency of the wave, f = 40 Hz

wavelength of the wave, λ = 0.79 m

Let the tension of the rope = T

The speed of the wave is given as;

[tex]v = f\lambda = \sqrt{\frac{T}{\mu} } \\\\where;\\\\\mu \ is \ mass \ per \ unit \ length\\\\\mu = \frac{0.105}{3} = 0.035 \ kg/m\\\\v = f\lambda = 40 \times 0.79 = 31.6 \ m/s\\\\v = \sqrt{\frac{T}{\mu} } \\\\v^2 = \frac{T}{\mu} \\\\T = v^2 \mu\\\\T = (31.6^2)(0.035)\\\\T = 34.95 \ N[/tex]

Therefore, the tension of the rope is 34.95 N

Answer:

it's a rule like water !!!!

Explanation:

Most importantly, time appears to run forward always never backwards. in other words there's perceived arrow of time and there's thermodynamic arrow of time, and they always point in a forward direction

for every system there are more states that seem chaotic then states that seem ordered.

the arrow of time seems to have something to do with that tendency. but to get from one instance to another where things get more entropy, we already need some kind of time, gotta admit that.

some (physicists) believe that time is an illusion, that the whole universe is already set in stone, like a block (the idea is therefore called block universe). from the perspective of a godlike outside observer the universe would be like a book, or a 4D movie. the characters might feel a movement of things in a direction, but rewinding it wouldn't feel different in any instance because the order in wich things happen is already written.

a different idea is that there are infinite many different futures and the further they are away, the less we can know for sure about them in a physical way. and this might also be work for the past, so that different parts could lead to one present.

when macroscopic information is deleted, it might not be reversible, so the past gets ultimately blurry. one example for deletion of macroscopic information this is the Library of Alexandria wich burned down.

all the quantum information is still conserved, but the order of things (like letters on pages) is lost and could have been in different configurations before. we can't ultimately not even see the past, as much as we would try.

personally the idea that the past is written in stone but the future is in flux doesn't make any sense for me. because than I could have free will now, but not from the perspective 10 days later.

the present would be a very special thing than, the stage where the universe likes to play.

maybe we can get a grasp on time if we look at it like rules for a game, like a cardboard game.

To get from one configuration to the next ,we must follow rules. like throwing dice and moving in monopoly.

gravity would be a simple real world example for such a rule, a natural law.

But no one would have a firm clue where this rules came from.

TLDR: I don't know and neither does anyone else for sure, not even top notch scientists.

the hardest questions are easy to formulate, but maybe even impossible for us to answer in a satisfying way. I hope we will understand those hard questions better one day, and maybe even get answers.

Answer:

9 seconds

Explanation:

[tex]acceleration = \frac{final \: speed - initial \: speed}{time \: taken} [/tex]

[tex]5km/ hr/ s = \frac{45 - 0 (km/ h)}{t} [/tex]

cross multiplying

[tex]5t = 45 secs \\ t = 9 \: secs[/tex]

it will take 9secs for the car to go from 0 to 45 km/ h

Answer:

The answer is "planetesimals".

Explanation:

The uncountable little corpses of the accreted gas and dust were supposed to orbit the Sun while the planets were formed. The theory explaining the creation of the solar system as a whole is termed the quark-gluon plasma hypothesis.

An object produced by dust, rock, and other materials is called a planetesimal. This word is rooted throughout the microscopic idea, which shows that an object is too small to observe or quantify. Everywhere from many meters to hundreds of kilometers asteroids may acquire size.

Answer:1200

Explanation:

F=ma =m(Vf-Vi)/t

F=120(25-5)/2 =1200N

Answer:

[tex]f = m \frac{v1 - v2}{t} \\ = 120 \times \frac{25 - 5}{2} \\ = 120 \times 10 \\ = 1200N \\ thank \: you[/tex]

Answer:56

Explanation: I did the test

Answer:

displacement

Explanation:

I hope ans will be right

[tex]\boxed{\large{\bold{\blue{ANSWER~:) }}}}[/tex]

[tex]\sf What \: is \: acceleration? \\ \\ \sf The \: rate \: of \: change \: of \: velocity \: of \: an \\ \sf object \: with \: respect \: to \: time \\ \sf is \: known \: as \: acceleration. [/tex]

Answer:

the statement is TRUE

Explanation:

Most lenses are made of glass that has a strong absorption below 400 nm,

Only special evaporation lenses are made of quartz and fused silica which has a high absorption below 200 nm.

therefore the statement is TRUE

Answer:

Explanation:

The equation for acceleration is

[tex]a=\frac{v_f-v_0}{t}[/tex] which is the final velocity minus the initial velocity divided by the time. I first need to put the units all in the same terms. We have the velocity given as km/hr, but the time is given in seconds and that's not gonna work. I will change the velocity to km/sec:

[tex]90\frac{km}{hr}*\frac{1hr}{3600s}=.025\frac{km}{s}[/tex] That's the value we will use for the final velocity of this car in the equation for acceleration:

[tex]a=\frac{.025-0}{10}=.0025\frac{km}{s^2}[/tex]

The second part of this problem asks how far the car travels in this 10 seconds. We just determined that the car can travel .025 km in 1 second, so in 10 seconds the car travels 10(.025) = .25 km

Answer:

Data given.

focal length (f)=15m÷2=7.5m

Distance of the object(U)=10m

Image distance (v)=?

Magnification (M)=?

Solution:

From:

1/f=1/u+1/v

1/7.5=1/10+1/v=75

then v=75m

Magnification, M=u/v

=75/10=7.5

Then magnification=7.5

Answer:

v = 30 m and m = 3

Explanation:

Given that,

The radius of curvature of the mirror, R = 15 m

Focal length, f = 7.5 m

Object distance, u = -10 m

We need to find the image distance and the magnification of the object.

Using mirror's formula,

[tex]\dfrac{1}{v}-\dfrac{1}{u}=\dfrac{1}{f}\\\\\dfrac{1}{v}=\dfrac{1}{f}+\dfrac{1}{u}\\\\\dfrac{1}{v}=\dfrac{1}{(7.5)}+\dfrac{1}{(-10)}\\\\v=30\ m[/tex]

The magnification of the object in mirror is given by :

[tex]m=\dfrac{-v}{u}\\\\m=\dfrac{-30}{-10}\\\\m=3[/tex]

So, the distance of the image from the mirror and the magnification of the object are 30 m and 3 respectively.

Answer:

b. they move in convection currents.

Explanation:

i learned this in 4th grade

Answer:

Physical Changes :- The substance in which no new substance is formed are called physical changes.

The molecular composition of the substance are totally same.

For example :- Crushing a mineral into powder.

Answer:

I = sum m *r^2    where m represents the (small) individual masses and r is the distance of that mass from center of rotation

Note:  sum m = M

For the hoop given all masses are at a distance RRR from the center of rotation

I = MMM * RRR^2