need help please and​

Answer:

your answer is 21 n

Explanation:

Answer:

The answer is 45 degree angle

Answer:

A plane mirror is a mirror with a flat (planar) reflective surface. For light rays striking a plane mirror, the angle of reflection equals the angle of incidence. The angle of the incidence is the angle between the incident ray and the surface normal (an imaginary line perpendicular to the surface).

Answer:

The moment of inertia depends on the following factors, The density of the material. Shape and size of the body. Axis of rotation (distribution of mass relative to the axis)

Answer:

In the electrons

Explanation:

The charge of ions of an element is determined by the amount of negative charged electrons are present. The protons and neutrons in the nucleus do not change.

Answer:

it is possible to use two icons in css content one below content 10px;color #99999

Answer:

The actions taken in the initial moments after a crisis matter. These steps can determine how disruptive the aftermath will be. With this in mind, companies need to plan for any potential incidents that could occur. In this blog post, we discuss the importance of emergency planning, the impact it has on a crisis and how to prepare for the worst.

Explanation:

hope you like it

Answer:

10m/s

Explanation:

Vf=v0+at

30m/s=v0+2.5m/s^2*8s

Solve for v0=10m/s

Sorry for the vague explanation I'm on my phone right now. Hope this still helps!

Initial velocity of the car where final velocity of a car is 30m/s and it is accelerating at a rate of 2.5 [tex]m/s^{2}[/tex] over an 2.8 [tex]m/s^{2}[/tex] 8 second period of time is 10 m/s.

To find the initial velocity of the car, we can use the kinematic equation:

Final velocity (v) = Initial velocity (u) + (Acceleration (a) * Time (t)).

Given the final velocity (v) as 30 m/s, acceleration (a) as 2.5 [tex]m/s^{2}[/tex], and time (t) as 8 seconds, we can plug these values into the equation:

30 m/s = u + (2.5 [tex]m/s^{2}[/tex] * 8 s).

Now, solve for the initial velocity (u):

30 m/s = u + 20 m/s.

Subtract 20 m/s from both sides:

u = 30 m/s - 20 m/s = 10 m/s.

Therefore, the initial velocity of the car is 10 m/s.

To know more about Initial velocity, here

brainly.com/question/28395671

#SPJ2

Answer:

b is correct!!!!!!!!!!!

The best transport electrons around an electrical circuit are connected in series. Thus, the correct answer would be option (B) are connected in series.

An alternating current (AC) circuits continuously switches the direction of electron flow back and forth, which can result in fluctuations in voltage and current.

On the other hand, in a direct current (DC) electrical circuit, the electrons flow in one direction, from the negative terminal of the power source to the positive terminal. This unidirectional flow of electrons provides a consistent and stable flow of electricity throughout the circuit.

Connecting components in series mean that they are connected end-to-end, and the current flowing through them is the same.

Overall, the best option to transport electrons around an electrical circuit are to connect in series.

Therefore, the correct answer would be option (B) are connected in series.

Learn more about alternating current (AC) here:

https://brainly.com/question/28305485

#SPJ6

Answer:

The density pf each piece will be the same, since density is defined as a mass per unit volume, so even when you cut an object it will not change

Answer:

Upward direction.

The friction is kinetic friction

Answer:

Blood group

Explanation:

Answer:

A. Blood group.

Explanation:

They could purely random genetic changes.

Answer:

D

Explanation:

Because you add them all up it equals 9

Answer:

472.36 N

Explanation:

The total mass with the tire and child would be 45 kg + 3.2 kg = 48.2 kg

Ft = force tension

Fg = force of gravity

Fnet=0 (because child is motionless and not accelerating)

0 = Ft - Fg

Ft = Fg

Ft = m*g

Ft = 48.2 kg * 9.8 m/s^2

Ft = 472.36 N

Hope this helps!!

A 45-kg child sits on a 3.2-kg tire swing. The tension of the rope is 472.36 N.

The parameters given in the question is

Mass of the child= 45 kg

Mass of the tire swing attached to the tree= 3.2 kg

The first step is to calculate the total mass. The total mass can be calculated as follows;

= Mass of the child + mass of the tire swing

= 45 + 3.2

= 48.2 kg

The tension can be calculated as follows,

= mass × acceleration

= 48.2 × 9.8

= 472.36

Hence, A 45-kg child sits on a 3.2-kg tire swing. The tension of the rope is 472.36 N.

Learn more about Tension,

brainly.com/question/21859711

#SPJ5

Answer:

1) The angle of projection of the ball is approximately 52.496° above the horizontal

2) The velocity with which the boy throws the ball to enable him accomplish his desire is approximately 14.769 m/s

Explanation:

In the projectile motion of the ball, the parameters are;

The distance the boy stands from the front of the house = 5 m

The depth of the house, front to back = 6 m

The height of the opening of the front window above him = 5 m

The height of the back window = 2 m higher than the front window

Therefore, the height of the back window = 5 m + 2 m = 7 m

1) The general formula for the vertical height of a parabolic projectile motion is given as follows;

y = a·x² + b·x + c

At y = 0, x = 0, therefore, c = 0

At y = 5, x = 5, we have;

5 = a·5² + b·5

∴ 5 = 25·a + 5·b...(1)

At y = 7, x = 11, we have;

7 = a·11² + b·11

7 = 121·a + 11·b...(2)

Making 'a' the subject of equation (1) and (2) and equating both values of 'a' gives;

For equation (1);

a = (5 - 5·b)/25 = 1/5 - b/5

a = 1/5 - b/5

For equation (2);

a = (7 - 11·b)/121 = 7/121 - b/11

a = 7/121 - b/11

∴ 1/5 - b/5 = 7/121 - b/11

1/5 - 7/121 = b/5 - b/11

86/605 = 6·b/55

b = (86/605) × (55/6) = 43/33

b = 43/33

a = 1/5 - b/5 = 1/5 - (43/33)/5 = -2/33

∴ y = (-2/33)·x² + (43/33)·x

The slope of the curve = dy/dx = d((-2/33)·x² + (43/33)·x)/dx = -4/33·x + 43/33

The slope of the curve at any point on the projectile = -4/33·x + 43/33

The slope at the origin is given by plugging x = 0  as follows

The slope at the origin = -4/33 × 0 + 43/33 = 43/33

The slope at the origin = tan(θ) = 43/33

Where;

θ = The angle of projection of the ball

∴ θ = arctan(43/33) ≈ 52.496°

The angle of projection of the ball, θ ≈ 52.496° above the horizontal

2) At the back widow, the equation for the vertical height, 'h', is given as follows;

[tex]h = (tan \angle \theta) \cdot x - \left(\dfrac{g}{2 \cdot v_1^2 \cdot cos^2 \angle \theta } \right )\cdot x^2[/tex]

Where;

h = The vertical height of the back window = 7 m

tan∠θ = 43/33

x = The horizontal distance of the back window from the boy = 5 m + 6 m = 11 m

g = The acceleration due to gravity = 9.8 m/s²

v₁ = The velocity with which the boy throws the ball

cos²∠θ = cos²(arctan(43/33)) = 1089/2938

Plugging in the values gives;

[tex]7 = \left (\dfrac{43}{33} \right) \times 11 - \left(\dfrac{9.8}{2 \cdot v_1^2 \cdot \dfrac{1089}{2938} } \right )\cdot 11^2[/tex]

[tex]\therefore v_1^2 = \dfrac{71981}{330}[/tex]

[tex]\therefore v_1 = \sqrt{\dfrac{71981}{330}} \approx \pm14.769[/tex]

The velocity with which the boy throws the ball to enable him accomplish his desire, v₁ ≈ 14.769 m/s.

Answer:

Velocity

Explanation:

I took the test.

Answer:

Given: V = 220V, Pmin = 360W, Pmax = 840W

For minimum heating case:

We know that

Pmin = VI

360 = 220 X I

I = 1.63 amp

R = V/I

R = 220/1.63

R = 134.96ohms

For maximum heating case:

We know that

Pmax = VI

840 = 220 X I

I = 3.81 amp

R = V/I

R = 220/3.81

R = 57.74 ohms

Answer:

The last one makes the most sense as they combine two like things that are easy to visualize

Explanation:

Answer:

C. The inner planets are like hard butterscotch candy and the outer planets are like cotton candy.

Explanation:

Right on ED2021, goodluck!

Answer:

I'm pretty sure its B and C

Explanation:

B bc the weight is gravitational pull x mass so when the object has same mass the weight is smaller on moon

C bc mass is the same - you can't change it

The correct answers are B and C

Answer:

Answer:answer is C

is the magnetic field

Answer:

a.) Maximum height of the projectile. =32.5m

b.) The time it takes to reach the maximum height=2.6s

c.) Time of flight=2.6s

d.) Range=99.5m

Explanation:

The baseball held 2 meters above the ground has more potential energy than the baseball held 1 meter above the ground.  

The potential energy can be calculated with the following equation:

[tex] E_{p} = mgh [/tex]

Where:

m: is the mass of the baseball

g: is the acceleration due to gravity

h: is the height

We can see from equation (1) that the potential energy depends on height, mass, and gravity. Since the question refers to the same baseball, the mass is constant besides the acceleration due to gravity, so:

[tex] E_{p_{1}} = mg*1 = mg [/tex]  (1)

[tex] E_{p_{2}} = mg*2 = 2mg [/tex]   (2)

By entering equation (1) into 2 we have:

[tex] E_{p_{2}} = 2mg = 2E_{p_{1}} [/tex]

Hence, the potential energy of the baseball held 2 m above the ground is twice that of the baseball held 1 m above the ground.

Therefore, the baseball held 2 m above the ground has more potential energy.

You can learn more about potential energy here: https://brainly.com/question/15813853?referrer=searchResults

I hope it helps you!

Answer:

i guess u could pick "B" :)

Explanation:

Answer:

The answer is "0.047".

Explanation:

Given value:

[tex]\to t_{\frac{1}{2}}= 0.4406\\\\\to V=0.9375 V_{max}[/tex]

Calculating the capacitance:

[tex]\to V=V_{max} (1-e^{\frac{-t}{Rc}})[/tex]

In this, the t = time, which is taken to calculates its maximum voltage.

[tex]\to 0.9375 V_{max} = V_{max}(1-e^{- \frac{t}{103\times(165.279\times10^{-6})}})\\\\\to e^{- \frac{t}{103\times(165.279\times10^{-6})}}= 0.0625\\\\\to - \frac{t}{103\times(165.279\times10^{-6})} = \ln(0.0625)\\\\\to -t= 0.01702\times(-2.77258) \\\\ \to -t = -0.04719 \\\\ \to t= 0.04719 \approx 0.047 \ s[/tex]

Answer:

40 hours

Explanation:

in 20 hours, 1/2 will decay

in 40 hours, 1/4 will decay

therefore, 40 hours

Answer:

Concave mirror

Explanation:

Because as we move the object far away from the mirror the image gets inverted

Answer:

[tex]1.2\times 10^{10}\ kg[/tex]

Explanation:

Given that,

The energy of the nuclear plant, [tex]E=10^{27}\ J[/tex]

We need to find how much mass wast lost.

The relation between energy and mass is given by :

[tex]E=mc^2[/tex]

Where

c is speed of light

[tex]m=\dfrac{E}{c^2}\\\\m=\dfrac{10^{27}}{(3\times 10^8)^2}\\\\m=1.2\times 10^{10}\ kg[/tex]

So, [tex]1.2\times 10^{10}\ kg[/tex] of mass was lost.