Quả bóng 200g chuyển động với v 4m/s đập vào tường rồi bật ra ngược chiều với cùng tốc độ độ biến thiên động lượng của quả bóng là

Answer:

Explanation:

[tex]a=\frac{v_f-v_0}{t}[/tex] We don't yet need the mass of the car, as we can see by this equation. What we do need is the velocity of the car, the initial velocity, in meters per second, and right now it's in km/hr. Not good. We need to convert. The conversion is as follows:

[tex]54\frac{km}{hr}*\frac{1000m}{1km}*\frac{1hr}{3600s}=15\frac{m}{s}[/tex] Ok, that's good. Now we have everything we need but the time element. If the car traveled a distance of 40 meters at 15 m/s, then we can use the d = rt equation to solve for t, and when we find t we plug it into the acceleration equation:

40 = 15t and

t = 2.7 seconds. The car traveled for 2.7 seconds to go that 40 meters. That's the only reason we were given the displacement. We need it for nothing else but that.

Filling in the acceleration equation now:

[tex]a=\frac{0-15}{2.7}=-5.6\frac{m}{s^2}[/tex] and the negative indicates we are in fact slowing down. That's the answer for the acceleration portion of the problem; now we need the force, F, applied to the brakes.

F = ma where m is mass (we get to use that value now!) and a is -5.6 m/s/s.

F = 500(-5.6) and

F = -2800 N and the negative here means that the force of the brakes is acting against the motion of the car: the brakes are pulling the car "backwards" to stop while the car's motion is forward. The negative indicates the direction the force is being applied.

Answer:

what do u need help with

Explanation:

Calculate the escape velocity for the spacecraft. [G= 6.67×10^-11Nm^2kg^-2, mass of the Earth= 5.97×10^24kg, radius of the Earth= ...

Answer:

Average speed = 0.35 m/s

Explanation:

Given the following data;

Distance = 1.3 Km

Time = 62 minutes

To find the average speed in m/s;

First of all, we would convert the quantities to their standard unit (S.I) of measurement;

Conversion:

1.3 kilometres to meters = 1.3 * 1000 = 1300 meters

For time;

1 minute = 60 seconds

62 minutes = X

Cross-multiplying, we have;

X = 62 * 60

X = 3720 seconds

Now, we can calculate the average speed in m/s using the formula;

[tex] Speed = \frac {distance}{time} [/tex]

[tex] Speed = \frac {1300}{3720} [/tex]

Average speed = 0.35 m/s

Answer:

The right hand rule states that, to find the direction of the magnetic force on a positive moving charge, the thumb of the right hand point in the direction of v, the fingers in the direction of B, and the force (F) is directed perpendicular to the right hand palm.

Explanation:

pls mark brainliest

Hope this helps u

Answer:

The northern lights come from the interaction of electrically charged particles given off by the Sun surface during solar storms and the Earth's magnetic field which is pointed in the northern to southern poles of the Earth. Therefore, the charged particles that travel through millions of miles from the Sun to the Earth accelerate towards the magnetic poles and appear as the northern (and southern) lights

Boreal is an adjective word for the north or northern regions. In the southern latitudes, in the southern hemisphere, the phenomenon is called aurora australis (australis is the adjective for 'of the south')

Explanation:

Answer:

68.6 m/s^2

Explanation:

1 g = 9.8 m/s^2

so

7 g × 9.8m/s^2 = 68.6

Answer:

yes

Explanation:

because the dipoles are not arrange the same way they were in the full hacksaw

Answer:

Explanation:

Because vectors have direction and x and y components you can't just add them and say that their length is 16 because A is 8 units and so is B. What you're actually finding is the magnitude and direction of the vector that results from this addition. The magnitude is the length of the resultant vector, which comes from the x and y components of A and B, and the direction is the angle between the resultant vector and the positive x axis. To add the vectors, then, we need to find the x and y components of each. We'll do the x components of A and B first so we can add them to get the x component of C. Since x values are directly related to cos, the formula to find the x components of vectors is

[tex]V_x=Vcos\theta[/tex] which is the magnitude of the vector (its length) and the angle. Finding the x components of A:

[tex]A_x=8.0cos45[/tex] so

[tex]A_x=5.7[/tex] and for B:

[tex]B_x=8.0cos180[/tex] since the negative x axis is the 180 degree axis and

[tex]B_x=-8.0[/tex] If we add them, we get

[tex]C_x=-2.3[/tex]

Now onto the y components. The formula for that is almost the same as the x components except use sin instead of cos:

[tex]A_y=8.0sin45[/tex] so

[tex]A_y=5.7[/tex] and

[tex]B_y=8.0sin180[/tex] so

[tex]B_y=0[/tex] If we add them, we get

[tex]C_y=5.7[/tex]

Now for the final magnitude:

[tex]C_{mag}=\sqrt{(-2.3)^2+(5.7)^2}[/tex] and

[tex]C_{mag}=6.1 units[/tex] and now onto the direction.

The x component of C is positive and the y component is negative, which means that the direction has us at an angle is quadrant 2; we add 180 to whatever the angle is. Finding the angle:

[tex]tan^{-1}(\frac{C_y}{C_x})=(\frac{5.7}{-2.3})[/tex] = -68 + 180 = 112 degrees

The resultant vector of A + B has a magnitude of 6.1 and a direction of 112°

Do the same thing for subtraction, except if you're subtracting B from A, the direction that B is pointing has to go the opposite way. That means that A doesn't change anything at all, but B is now pointing towards 0.

[tex]A_x=5.7[/tex] (doesn't change from above)

[tex]B_x=8.0cos0[/tex] and

[tex]B_x=8.0[/tex] so

[tex]C_x=13.7[/tex] and

[tex]A_y=5.7[/tex] (also doesn't change from above)

[tex]B_y=8.0sin0[/tex] so

[tex]B_y=0[/tex] and

[tex]C_y=5.7[/tex] and for the magnitude:

[tex]C_{mag}=\sqrt{(13.7)^2+(5.7)^2[/tex] so

[tex]C_{mag}=15units[/tex] and for the direction:

[tex]tan^{-1}(\frac{5.7}{13.7})=23[/tex] and since both x and y components of C are in Q1, we add nothing.

And you're done!!!

Explanation:

Ultrasound refers to sound waves having frequencies greater than the frequency range limit. Ultrasound has the same physical qualities as "regular" (audible) music, except that individuals cannot hear it. Ultrasound devices use frequencies ranging from 20 kHz to a few gigahertz.

The frequencies of ultrasound utilised in clinical settings are generally between 2 and 12 MHz. Shorter wavelengths have a larger penetration depth into the body but less resolution; longer wavelengths have a greater depth of penetration but have a restricted depth of penetration.

Explanation:

C. Both energy and matter

Answer:

0.48N

Explanation:

according to the second law of motion

force=mass×acceleration

the mass in this question is 0.025,the acceleration 19

therefore f=0.025×19

=0.48N

I hope this helps

Explanation:

electrical energy into heat energy

electrical , thermal

Answer:

Two or more capacitors are said to be connected in parallel if each one of them is connected across the same two points. In a parallel combination of capacitors potential difference across each capacitor is same but each capacitor will store different charge.

Answer:

B. It has mass

Explanation:

The Newtons Universal gravitacion law is : F = G.[tex]\frac{m1 m2}{d^{2} }[/tex]  , where F is the force exerted , m1 and m2 are the earth's mass and the object's mass, d is the distance and G the gravitacional constant. Comparing to the options we can say that the Earth exerts a gravitational force on objects on its surface because of its mass.

Answer:

2 m/s^2

Explanation:

a = ∆v / ∆t

a = (50 - 30) / 10

a = 20 / 10

a = 2 m/s^2

acceleration = u-v/t

50-30/10

=2m/s

Answer:

600 volts

Explanation: just do 4.5x10^-5c lol i hope this helps if it dont im so sorry

Answer:

it gravitional pull on earth will increased becauste it is compress to a form of moon which is comperatively smaller so the gravitonal pull on per cm of earth will incrased so we can say that there will be change in acceleration due to gravity

Converse:

if q , then p

Inverse:

If not p , the not q.

Contra Positive:

If not q, then not p.

If then statement is a conditional statement. In this statement there is some condition at the first part of the sentence and then in the second part there is a conclusion.

The example of if then sentence is as follows,

If this camel is thirsty, then it will drink water from the well.

In this example there is a condition in first part that if camel is thirsty, in the second part there is conclusion which states that then it will drink water from well.

Learn more at https://brainly.com/question/24294393

Answer:

plastics are unable to conduct electricity and heat due to there being no free flowing electrons, meaning they are safe to use.

Explanation:

Answer:

nothing

Explanation:

bocouse of darkness

Answer:

wah wats this again

Explanation:

Bhai mujhe samaj nahi ah Raha

Kya Bolne Chahtaa hu tum

Answer:

bạn vẽ ra rồi làm

Explanation:

Answer:

57

Explanation:

Answer: I hope you find it useful

Explanation: Group 2 elements have two valence electrons. The two valence electrons are easily lost in the formation of chemical bonds. Once the two electrons are lost, the atom then has a full outer shell and is therefore more stable.

so,  if an atom has valency 2 , then it means that the atom can combine with 2 other atoms .

Answer:

HOPE IT HELP YOU A LOT :)

I prove it also .

Answer:

Newtons Second law of motion states that"The rate of change of momentum is directly proportional to the force applied"

Answer:

Reduction in recoverable amount

Explanation:

Impairment of an asset happens when there is drastic reduction in recoverable amount of the asset. Long term assets are at risk of impairment because their carrying values may exceed the fair value. The business record it as a loss in assets value.

Answer:

accelerating.

Explanation:

A horse is running on a circular path with constant speed but its direction is changing at every point. Thus, it is accelerating.

personal to systematic errors

unbiased to random errors

Answer:

A

in performing the experiment the hypothesis is proved wrong or correct prediction , meaning of prediction is guessing,

hypothesis the second stage of scientific method , scientist predict or guess the answer to the problem ,

Experiment the third stage of scientific method

scientist examine the ways

"Perform the experiment" is the step of the scientific method where a scientist determines whether the hypothesis was supported.

In the scientific method, experiments (often with controls and variables) are devised to test hypotheses. In the scientific method, analysis of the results of an experiment will lead to the hypothesis being accepted or rejected.

The basic idea of a hypothesis is that there is no predetermined outcome. For a solution to be termed a scientific hypothesis, it has to be an idea that can be supported or refuted through carefully crafted experimentation or observation.

Learn more about the hypothesis here https://brainly.com/question/11555274

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