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Answer:

28 m/s

Explanation:

We can use this constant acceleration kinematic equation to find the speed of this beam as it is dropped from 40 m.

Since the object is dropped vertically downwards, we know that the object is in free-fall.

The acceleration of this object is -g, which is -9.8 m/s² since we are making the positive direction upwards and the negative direction downwards.

The initial velocity is 0 m/s since the object is dropped and starts from rest.

The final velocity is what we are trying to solve for.

The displacement in the y-direction is 40 m.

Now we can see which equation contains these 4 variables:

Plug in the known variables.

Simplify this equation.

Take the square root of both sides.

The speed of the 330 kg beam dropped from 40 m is 28 m/s.

Answer:

Explanation:

Given information :

mass = 330kg

height =40m

v = √2gh

Where ;

g = acceleration due to gravity = 9.8 or 10 m/s

h = height

how much total energy of the beam just as it hits the ground =

mgh

[tex]330\times 10\times 40\\\\\\=132000[/tex]

Speed at which  the beam will hit the ground :

[tex]v = \sqrt{2\times 10\times40} \\\\=\sqrt{800}\\\\=20\sqrt{2}\\\\v=28.28427[/tex]

Answer:

.

Explanation:

.

Answer:

We could reduce the force or increase the mass of the object.

Explanation:

Using the definition of force, according to Newton's second law,  (F = ma) the acceleration is directly proportional to the force and inversely proportional to the mass. Therefore, if we want to reduce the acceleration of an object we have two options:

In both cases a will decrease.  

I hope it helps you!

Answer:d

Explanation:

Answer:

A & D

Explanation:

A single-displacement reaction is a chemical reaction whereby one element is substituted for another one in a compound and thereby generating a new element and also a new compound as products.

From the options, only options A & D fits this definition of single-displacement reactions.

For option D: Both left and hand and right hand sides each have one element and one compound. We can see that K is substituted from KBr to join Cl to form KCl and Br2 on the right hand side.

For option A: Both left and hand and right hand sides each have one element and one compound. We can see that OH is substituted from 2H2O to join Mg to form Mg(OH)2 and H2 on the right hand side.

The other options are not correct because they don't involve only and element and a compound on each side of the reaction.

Note that when the ball is in the air, the only force acting on it is the downward pull of gravity, so the force of the swing is a red herring.

The ball hits the ground at the same height from which it was hit, so its final velocity will have the same magnitude of 49 m/s, but pointing at an angle of 35° below the horizontal.

Answer:

D

Explanation:

Answer:

Astronomical Unit = 4.8481×10−6 pc; 1.5813×1.

Or even AU = Equal to

Explanation:

Given :

An electron with kinetic energy of 3 MeV.

To Find :

The de-Broglie wavelength for that electron.

Solution :

We know, de-Broglie wavelength for an electron with kinetic energy K.E is given by :

[tex]\lambda = \dfrac{h}{\sqrt{2m(K.E)}}[/tex]

Putting all given values in above equation, we get :

[tex]\lambda = \dfrac{6.626\times 10^{-34}}{\sqrt{2\times 9.1\times 10^{-31}\times 3\times 10^6 \times 1.6\times 10^{-19}}}\\\\\\\lambda = 7.089 \times 10^{-13} \ m[/tex]

Hence, this is the required solution.

Answer:

true false

Explanation:

Answer:

1.true

2.true

3.true                              4.false                        5.true

Answer:

1. The acceleration would increase.

Explanation:

This is because according to Newton's law, the less mass there is, the more velocity.

Answer: wavelength is the length of the wave, example the length of a sound wave.

Velocity is also known as speed.

Explanation:

Answer:

The lower fixed point, or ice point, is the temperature of pure melting ice at normal atmospheric pressure. The upper fixed point, or steam point, is the temperature of pure boiling water at normal atmospheric pressure.

Explanation:

Answer:

To answer your question use the code ICE on here to get your answer works every time for me hope this helps

Answer:

10 m/s

Explanation:

Speed = Distance / Time

Speed = 400 / 40

Speed = 10

Unit = meters per second = m/s

Answer:

Vr = 20 [km/h]

Explanation:

In order to solve this problem, we have to add the relative velocities. We must remember that velocity is a vector, therefore it has magnitude and direction. We will take the sea as the reference measurement level.

Let's take the direction of the ship as positive. Therefore the boy moves in the opposite direction (Negative) to the reference level (the sea).

[tex]V_{r}=30-10\\V_{r}=20 [km/h][/tex]

Answer:

  capacitive

Explanation:

In a capacitive circuit, current is proportional to the derivative of the voltage. For a sinusoidal excitation, this means current is at the highest level when voltage is increasing through zero. That is, current leads the voltage.

Answer:

D

Explanation:

If two unequal forces act in opposite directions, one larger force must cancel out the smaller force,

leaving the net force to be some number in one direction.

Take for example a game of tug-of-war; there are two  OPPOSITE forces (groups of people) acting on the rope, one force is pulling with a force in the negative direction while the other force is pulling in the positive direction.

If the forces on the rope were unequal, then the stronger force (group) will pull everything in their direction.

The same will happen on two unequal forces of opposite directions acting on a wooden block. Therefore, since the resultant force will have a non-zero magnitude and direction, there will be a change in the block's motion and position.

Answer:

[tex]F_{g}=7.4704\times10^{-5}[/tex]

Explanation:

Givens: d = 1.0 × [tex]10^{4}[/tex]  [tex]m_{1} = 4.0 x 10^{8}[/tex]  [tex]m_{2} = 2.8[/tex]×[tex]10^{5}[/tex]

Required: [tex]F_{g}=?[/tex]

Formula:  [tex]F_{g}= \frac{(6.67x10^{-11})(m_{1})(m_{2}) }{d^{2}}[/tex]    (6.67x10^-11  is the gravitational constant)

[tex]F_{g}=\frac{\left(6.67\cdot10^{-11}\right)\left(4.0\cdot10^{8}\right)\left(2.8\cdot10^{5}\right)}{\left(1.0\cdot10^{4}\right)^{2}}[/tex]

[tex]F_{g}=7.4704\times10^{-5}[/tex]

Answer:

is changing in direction, but constant in magnitude

Explanation:

This question is a bit tricky since the velocity of the satellite is changing, but the speed is constant.

Speed is simply a measure of how fast you are going. It doesn't matter where you're going, just how quickly.

Velocity, on the other hand, does care about which direction you're going. For example, it could be then when you travel right, your velocity is positive, and when you travel left, your velocity is negative. This is the similar for a 2D shape like a circular orbit

Since we know velocity is changing, there must be acceleration which changes that velocity (since acceleration is the change in velocity: going from 0 to 60 mph, for example)

Thus, with a non-zero net acceleration, we know that there must be a force that is changing in direction, but constant in magnitude (since the orbit is a circle, and always attracted to the center of the Earth at equal distance).

Explanation:

list in order with the smallest molecules at the top and largest molecules at the bottom:

1.Oxygen

2.Water

3.Carbon dioxide

4.amino acid

5.Glucose

6. Starch

7. Protein

The molecules can be arranged as follows with the smallest at the top is oxygen, water, carbon dioxide, amino acid, glucose, starch, protein.

The given molecules;

starch, water, glucose, carbon dioxide, protein, amino acid, oxygen

The molecular weight of the given compounds is listed as follows;

water -------- 18 g/mol

glucose -------  180.2 g/mol

starch (2 or more glucose) ------ 360 g/mol

carbon dioxide ------ 44 g/mol

protein -------- 20,000 g/mol

amino acid (glycine) ----- 75 g/mol

oxygen -------- 16 g/mol

Thus, the molecules can be arranged as follows with the smallest at the top;

Learn more here:https://brainly.com/question/19537339

Answer:

150 steps south

Explanation:

250 north 250 back to start then continue south for remainder of 400 steps. 150 south

Answer:

The value is [tex]\lambda = 0.335 \ m[/tex]  

Explanation:

From the question we are told that

     The length of the string is  [tex]l = 0.67 \ m[/tex]

      The mass is  [tex]m = 2.0 \ g = 0.002 \ kg[/tex]

      The frequency produced at  fourth harmonic vibration(i.e n =4 )  is  [tex]f = 700 \ Hz[/tex]

  Generally the wavelength of the string is  mathematically represented as

            [tex]\lambda = \frac{ 2L }{n }[/tex]

=>          [tex]\lambda = \frac{ 2 * 0.67 }{ 4 }[/tex]  

=>          [tex]\lambda = 0.335 \ m[/tex]  

Answer:

1.7 g/cm³

Explanation:

Given that:

Density of substance = 3.4 g/cm³

Relative density to another substance = 2

Density of second substance=?

Let density of second substance = x

Relative density = density of substance / density of second substance

Relative density = density of substance / x

2.0 = 3.4g/cm³ / x

2 * x = 3.4 g /cm³

x = 3.4 g/cm³ ÷ 2

x = 1.7 g/cm³

Answer:

i dont know the answer sorry have a good day

Explanation:

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Answer:

417.5 kg

Explanation:

Since the gravitational for of attraction F, equals the weight of the object W when its close to the earth, F = GMm/R² = W = mg where m = mass of object and g = acceleration due to gravity close to the earth = 9.8 m/s².

g = GM/R² where  g = acceleration due to gravity close to the earth, G = universal gravitational constant = 6.67 × 10⁻¹¹ Nm²/kg², M = mass of earth = 5.927 × 10²⁴ kg and R = radius of earth = 6.4 × 10⁶ m

So, g = GM/R²

= 6.67 × 10⁻¹¹ Nm²/kg² × 5.927 × 10²⁴ kg/(6.4 × 10⁶ m)²

= 39.53 × 10¹³ Nm²/kg ÷ 40.96 × 10¹² m²

= 9.65 N/kg

≅ 9.7 N/kg

= 9.7 m/s²

Since W = 4050 N and W = mg

m = W/g = 4050 N/9.7 m/s²

= 417.53 kg

≅ 417.5 kg

So, the mass of the object is 417.5 kg

Answer:

v = 10.85 m/s

Explanation:

We will apply the law of conservation of energy to the skateboarder. Neglecting the frictional effects, the law of conservation of energy can be written as:

[tex]Loss\ in\ Potential\ Energy\ of\ Skateboarder = Gain\ in\ Kinetic\ Energy\ of\ Skateboarder[/tex][tex]mg\Delta h = \frac{1}{2}mv^2\\\\v^2 = 2g\Delta h\\v = \sqrt{2g\Delta h} \\[/tex]

where,

v = velocity of skateboarder = ?

g = acceleration due to gravity = 9.81 m/s²

Δh = change in height = 10 m - 4 m = 6 m

Therefore,

[tex]v = \sqrt{{(2)(9.81\ m/s^2})({6\ m})}}[/tex]

v = 10.85 m/s

Answer:

(1) chess is played by him

(2) The great black engine was seen by her

(3) Arrangements for functions had been made by him

(4) A meeting is being attended by Raman

= when the last of the guests left, I went back into the hall to look for my mobile phone that I had kept on the table, I found that my mobile phone was not there. I felt freaked and I asked to every member of my family about my phone, but nobody had idea about that. then there was a phone call made by my uncle to my father, that his son had taken the mobile by mistake. After sometime, My uncle came to return my mobile. Then I took a sigh of relief .

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Answer:

The work done by Ramas is 3920 N.

Explanation:

Given;

mass of the load lifted by Ramas, m = 20 kg

height through which the load is lifted, h = 20 m

The work done by Ramas is equal to gravitational potential due to the height in which the load is lifted.

W = PE = mgh

where;

g is acceleration due to gravity = 9.8 m/s²

W = 20 x 9.8 x 20

W = 3920 N.

Therefore, the work done by Ramas is 3920 N.