Two ice skaters are at rest and facing each other. In order to move, they push
off each other. What is known about their final total momentum?
A. One skater must remain at rest.
B. Nothing is known about the final total momentum.
C. The final total momentum must equal zero.
D. Since they are on ice, this will not work. Neither can move.

Answer:

The second one

Answer:

The highness or lowness of sound

Explanation:

(a) The velocity of the apple with respect to the road is 100 km/h.

(b) The velocity of the apple with respect to you is 0 km/h.

(c) If you drop the apple the horizontal velocity will not change due to law of conservation of linear momentum.

The relative velocity of the apple placed over your with respect to the road is calculated as follows;

Velocity of the apple = 100 km/h

Velocity of the road = 0 km/h

Va/r = 100 km/h - 0 km/h

Va/r = 100 km/h

The velocity of the apple relative to you is calculated as follows;

your velocity = 100 km/h

velocity of the apple = 100 km/h

Va/y = 100 km/h - 100 km/h

va/y = 0 km/h

If you drop the apple, the horizontal velocity will remain the same, because gravity does not affect horizontal motion.

The law is law of conservation of linear momentum.

Learn more about relative velocity here: https://brainly.com/question/17228388

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Answer:

The answer is actually a. Cathode

Explanation:

Just took the quiz

In an electrolytic cell, the reduction occurs at the cathode. So, the correct option is a.

Reduction is defined as the process through which a reactant gain electrons during a chemical reaction.

Here,

An electrolytic cell is an equipment that uses electric current to drive a redox reaction.

Redox reactions are the type of reaction that involves the transfer of electrons between the reactants. That means, in redox reactions, both oxidation and reduction occurs. The reactant that gains the electrons is said to be reduced and the one that losses the electrons is said to be oxidized.

In an electrolytic cell, cathode is the positively charged electrode. So, electrons are attracted towards it, and as a result, the cathode gets reduced.

Hence,

In an electrolytic cell, the reduction occurs at the cathode.

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Answer:

a. 3.68 m b. 0.61 m c. 3.07 m

Explanation:

a. What is the maximum height the ball reaches on the moon?

Using v² = u² - 2g'h where u = initial velocity of baseball = 12 m/s, v =  final velocity of baseball = 0 m/s (since it stops at maximum height), g' = acceleration due to gravity on moon = g/6 where g = acceleration due to gravity on earth = 9.8 m/s², so g' = 9.8 m/s²/6 = 1.63 m/s² and h = maximum height of ball on moon.

So, making h subject of the formula, we have

h = -(v² - u²)/2g'

substituting the values of the variables, we have

h = -((0 m/s)² - (12 m/s)²)/2(1.63 m/s²)

=  -(- 12 m²/s²)/2(1.63 m/s²)

= 6 m²/s²)/(1.63 m/s²)

= 3.68 m

b. What is the maximum height the ball reaches on the earth?

Using the same equation for the maximum height the baseball travels on the moon for that on the earth, the maximum height h' the baseball travels on the earth is given by  

h' = -(v² - u²)/2g where u = initial velocity of baseball = 12 m/s, v =  final velocity of baseball = 0 m/s (since it stops at maximum height),  g = acceleration due to gravity on earth = 9.8 m/s²and h' = maximum height of ball on moon.

substituting the values of the variables, we have

h = -((0 m/s)² - (12 m/s)²)/2(9.8 m/s²)

=  -(- 12 m²/s²)/2(9.8 m/s²)

= 6 m²/s²)/(9.8 m/s²)

= 0.61 m

c. What is the difference in the maximum height the ball reaches on the Moon compared to on Earth?

The difference in the maximum height the ball reaches on the Moon compared to on Earth is d = h - h' = 3.68 m - 0.61 m = 3.07 m

Answer:

a change in velocity can be a change in magnitude (or speed), but it can also be a change in direction.

Answer:it would make it thicker

Explanation:

Answer:

"The equation shows that the current in a circuit is inversely proportional to the resistance of the circuit. An increase in resistance would result in a decrease in current. And the factor by which the resistance increases is the same factor by which the current decreases."

Explanation:

Because it's just like wearing a glove/mitten when getting something out of the oven, because of the insulation from the glove/mitten, it reduces the heat that gets through into your hand, and it protects it. Just like what the "answer" says, it said that the resistance would decrease current.

Answer:

75 miles an hour

I hope this is correct and helps

Answer:

displacement is the change from a starting point. she ends up back where she started so her displacement is zero meters although she traveled 24m in all.

Answer:

idgaf

Explanation:

lol

. . .

. . .

. . .

!

.

Your answer is 0.30 seconds

Answer:

4 m/s^2

that is the right acceleretion a car

Answer:

I believe that the answer is 3 m/s^2

Explanation:

since acceleration is final velocity minus initial velocity divided by time, we can plug in known values and solve.

a=(f-i)/t

a=(16-4)/4

a=12/4

a=3

3m/s^2 is the acceleration

Answer:

10 m/s

Explanation:

The complete question is

A 45-kg child sits on a 3.2-kg tire swing. The tension on the rope is 470 N. The tree branch sags and the child's feet rest on the ground. If the tension in the rope is reduced to 220 N, what is the value of the normal force being exerted on the child's feet?

Answer:

Therefore the Normal force is being exerted on the child's feet is 252.36( 250N).

Explanation:

We are given

mass of child = 45kg

mass of the tire = 3.2kg

g = 9.8 m/s^2

We have the first case in which the tire is in swing so tension in that case will be which is the resultant force.

Fr = Resultant force

Ft =  Tension force

Fg= Gravitational force

Fr = Fg + Ft

0 = -mg + Ft

Ft = mg

   = (45+3.2)*9.8

   = 48.2 * 9.8

Ft = 472.36N  ( which is close to 470)

In the second case the child is in the rest position, The resultant force will be zero.

Fr = Ft + Fn + Fg  ( Normal force is denoted by Fn )

0 = Ft + Fn + Fg

Fn =  -Fg -Ft

Fn = mg -Ft

    = 472.36 - 220

Fn  = 252.36N  ( close to 250N)

Therefore the Normal force being exerted on the child's feet will be 252.36N.  

Answer:

the answer would be B

Explanation:

swelling is the result of the increased movement of fluid and white blood cells into the injured area.

Answer:

333 m

Explanation:

The following data were obtained from the question:

Initial velocity (u) = 0 m/s.

Time (t) = 8.14 s.

Final velocity (v) = 80.79 m/s.

Acceleration due to gravity (g) = 9.8 m/s²

Height (h) =?

v² = u² + 2gh

80.79² = 0 + (2 × 9.8 × h)

6527.0241 = 0 + 19.6h

6527.0241 = 19.6h

Divide both side by 19.6

h = 6527.0241 / 19.6

h = 333 m

Thus, the plane was at a height of 333 m when the package was dropped.

Answer:

reference point

Explanation:

you can use a reference point to tell when an object is in motion or staying still. :)

Answer:

forever

Explanation:

Answer:

1.)Evaporation, 2.) solid

Explanation:

hope this helps can i get brainliest

Answer:

Explanation:

The force acting on an object given it's mass and acceleration can be found by using the formula

force = mass × acceleration

From the question we have

force = 50 × 5

We have the final answer as

Hope this helps you

Answer:

Winter

Explanation:

Answer:

it has the same mechanicals as a baseball

Explanation:

Answer:

A. i think

Explanation:

Answer: 121.2 m/s

Explanation:

Here we will use the conservation of energy.

We can write the total energy of an object as:

E = K + U

For this particular case we have:

K = kinetic energy = (m/2)*v^2

U = potential energy = m*g*h

where:

m = mass of the object.

g = gravitational acceleration = 9.8m/s^2

h = height at which the object is dropped, in this case 750m

v = velocity of the object.

Right when the packet is dropped, it's velocity is equal to zero, this means that there is no kinetic energy and only potential energy, then we have:

Ei = Ui = m*9.8m/s^2*750m = m*(7350m^2/s^2)

And when the object is about to hit the ground, h will be almost equal to zero, this will mean that we will have only kinetic energy, and because of the conservation of energy, this final energy must be the same as the initial energy, then we will have

Ei = Ef

m*(7350m^2/s^2) = Ef = Kf

m*(7350m^2/s^2) = (m/2)*v^2

We can divide by m in both sides to get:

(7350m^2/s^2) = (1/2)*v^2

√( 2*(7350m^2/s^2)) = v = 121.2 m/s

Then the velocity of the packet when it reaches the ground is 121.2 m/s

Answer:

Correct choice: b 4H

Explanation:

Conservation of the mechanical energy

The mechanical energy is the sum of the gravitational potential energy GPE (U) and the kinetic energy KE (K):

E = U + K

The GPE is calculated as:

U = mgh

And the kinetic energy is:

[tex]\displaystyle K=\frac{1}{2}mv^2[/tex]

Where:

m = mass of the object

g = gravitational acceleration

h = height of the object

v = speed at which the object moves

When the snowball is dropped from a height H, it has zero speed and therefore zero kinetic energy, thus the mechanical energy is:

[tex]U_1 = mgH[/tex]

When the snowball reaches the ground, the height is zero and the GPE is also zero, thus the mechanical energy is:

[tex]\displaystyle U_2=\frac{1}{2}mv^2[/tex]

Since the energy is conserved, U1=U2

[tex]\displaystyle mgH=\frac{1}{2}mv^2 \qquad\qquad [1][/tex]

For the speed to be double, we need to drop the snowball from a height H', and:

[tex]\displaystyle mgH'=\frac{1}{2}m(2v)^2[/tex]

Operating:

[tex]\displaystyle mgH'=4\frac{1}{2}m(v)^2 \qquad\qquad [2][/tex]

Dividing [2] by [1]

[tex]\displaystyle \frac{mgH'}{mgH}=\frac{4\frac{1}{2}m(v)^2}{\frac{1}{2}m(v)^2}[/tex]

Simplifying:

[tex]\displaystyle \frac{H'}{H}=4[/tex]

Thus:

H' = 4H

Correct choice: b 4H

Answer:60 W

Explanation:

Answer:

false

Explanation: