15. Find the density of a certain object that has the dimensions 2cm x 6cm x 7cm and a
mass of 42g.
16. What is the volume of a container of liquid that has a density of 120g/ml and a mass
of 17g.
17. If the mass of an object has a mass of 23g and a volume 123ml, what is its density.
“Express your answer in Kg/ml!"
18. What is the volume of a cubed object with a measure of 12cm on one of its sides, if
the mass of that same object is 45g and its density is 240g/cm3?
19. An object with a density of 3g/ml is placed into a body of water. Since the density of
water is 1g/ml, will this object sink or float.

Answer:

Iron, cobalt, and nickel are the only three naturally occurring elements that are magnetic. 

Explanation:

hope it helps

correct me if I'm wrong thank you

brainliest please

Answer:

The three elements that can be used to make a magnet are :

Aluminum, nickel and cobalt

Answer:

B.

Explanation:

Density = mass / volume

= 0.01/0.05

= 0.2 kg/m^3.

To make the boiler more efficient, we would replace the resistor with another double the length.

We know that the resistance of the resistor in the boiler is given by R = ρl/A where

Also, the power generated by the resistor is P = i²R where

If i is constant, we see that P ∝ R.

So, to increase the efficiency, the value of the resistance has to increase.

Also, since R = ρl/A and ρ and A are constant, we see that R ∝ l.

Since P ∝ R and R ∝ l ⇒ P ∝ l.

So, to increase the efficiency, we would double the length of the resistor.

So, to make the boiler more efficient, we would replace the resistor with another double the length.

Learn more about resistors here:

https://brainly.com/question/25209910

Answer:

I just put a random number for the work

Explanation:

I hope it is ok.

The acceleration of the first block (4 kg) is -9.8 m/s².

The given parameters:

The net force on the system of the two blocks is calculated as follows;

[tex]m_2 g - T = m_1 a[/tex]

where;

[tex]m_2 g - m_1 g = m_1 a\\\\a = \frac{m_2 g - m_1g}{m_1} \\\\a = \frac{g(m_2 - m_1)}{m_1} \\\\a = \frac{9.8(2-4)}{2} \\\\a = -9.8 \ m/s^2[/tex]

Thus, the acceleration of the first block (4 kg) is -9.8 m/s².

Learn more about net force on two connected blocks here: https://brainly.com/question/13539944

Answer:

1) A 1L bottle, with a height of 30cm, full of water is emptied. The bottle is filled with oil (density = 920 kg/m^3). Calculate the change in pressure of the bottom of the first bottle. If you decide to put potatoes (assume its density is  1,8 kg/m^3), each one of a volume V = 10 cm^3, will they float?

2) The fusion temperature of the Nitrogen is -210°C and its boiling temperature is 77K. Calculate the difference between the fusion temperature and the boiling temperature.

Answer:

The gravity helps the planets stay together near the Sun, without it Earth would be floating away with the planet eventually becoming frozen up, thus the role gravity have in the motion of planets around the sun is by keeping them together.

Explanation:

Hope this helps!

Answer:

C)

Explanation: In freefall motion object always has gravity as its acceleration.

Answer:

Astronomers think there are between 1.1 and 1.9 million asteroids in the solar system.

Explanation:

Answer: false

Explanation:

Answer:

100

Explanation:

1. • Here, force of gravity on the block = 20 N.

• Therefore, the normal force will also be the same, i.e., 20 N [According to Newton's Third Law, on every action, there is an equal and opposite reaction]

• The coefficient

[tex] u_{k} = 0.4[/tex]

• Force of friction =

[tex]u_{k} \times \: normal \: \: \: force \\ = 0.4 \times 20N \\ = 8N[/tex]

• Hence, the force of sliding friction between the block and the ground is 8 N.

• So, it is option c. 8 N

2. The answer is option d. continue in the same direction with no change in speed.

We know, force = mass × acceleration. When force is 0, then acceleration will also be 0 since mass cannot be 0. So, there will be no change in speed.

3. It is option b. force that is required to give a one kilogram object the acceleration of 1 m/s^2.

Newton is the SI unit of force. As mentioned earlier, force = mass × acceleration. The SI unit of mass and acceleration is Kg and m/s^2 respectively.

So, 1 N = 1 Kg × 1 m/s^2.

4. It is d. not zero.

Acceleration is the change in speed. So, if the force is zero, then acceleration will not occur.

5. Force = 2 N

Acceleration of the object A = 2 m/s^2.

Acceleration of the object B = 1 m/s^2.

Therefore, mass of the object A = 2 N ÷ 2 m/s^2 = 1 Kg

And, mass of the object B = 2 N ÷ 1 m/s^2 = 2 Kg

So, the mass of object B is greater than that of object A.

Hence, the answer is option c. Object B has more mass.

Hope you could get an idea from here.

Doubt clarification - use comment section.

This is because the cloth soaked in water can absorb and evaporate the heat from your forehead.

This technique is used to cool down your fever, and to help you feel better.

Answer:

Friction

Explanation:

As the skateboarder goes down the ramp, potential energy is converted to kinetic energy. Because of friction, some of the energy in the system is converted to heat energy. Once the kinetic energy is converted to heat, the energy cannot be converted back to the potential or kinetic energy in the system.

[tex]\\ \sf\Rrightarrow V=\dfrac{W}{Q}[/tex]

[tex]\\ \sf\Rrightarrow V=\dfrac{9}{1}[/tex]

[tex]\\ \sf\Rrightarrow V=9V[/tex]

did you end up getting the answer- im struggling

Answer:

I would think human error could cause differences like not pressing the stop watch on time.

Explanation:

Newton's second law and the kinematic relations allow to find the results for the questions about forces and the movement of the block are:

    B) the force applied to maintain the system is equilibrium is: F = 0.39 N with an angle of tea = 180º

    C) The maximum force is: F = 24 N

    D) The time to stop the block is: t = 25 s

Newton's second law establishes a relationship between the net force, the mass, and the acceleration of the body. In the special case that the acceleration is zero it is called the equilibrium condition.

B) They indicate a diagram of forces on the block, let's look for the components of the force that the block maintains with zero acceleration, in the attached we have a free-body diagram including the force applied to keep the system in equilibrium.

x-axis

      -10 + 12 sin 60 + Fₓ = 0

        Fₓ = 10- 12 sin 60 = -0.39 N

y-axis

       12 cos 60 - 6 + F_y = 0

        F_y = 6 - 12 cos 60 = 0 N

We can give the result of the force in two ways:

Let's use Pythagoras' theorem to find the modulus.

       [tex]F = \sqrt{F_x^2 + F_y^2 } \\F = \sqrt{0.39^2 +0^2}[/tex]  

       F = 0.39N

We use trigonometry for the angle.

       [tex]tan \theta = \frac{F_y}{F_x}[/tex]

       tan θ=  0º

The component of the force is negative therefore this angle is in the second quadrant, to measure the angle from the positive side of the x axis in a counterclockwise direction.

        θ = 180 + θ'

        θ = 180 + 0

        θ = 180º

C) if the three forces can be moved and the maximum force occurs when they are all linear.

          10+ 6 + 6 + F = 0

          F = -24 N

D) if we maintain this force and eliminate the other three, the block stops, let's look for its acceleration.

          [tex]a = \frac{F}{m}[/tex]  

          a = [tex]\frac{24}{6}[/tex]  

         a =  4 m / s²

The acceleration is in the opposite direction of the initial velocity of the block v₀ = -100 m / s

If we use kinematic relations.

        v = v₀ - a t

Final velocity when stopped is zero

         t = [tex]\frac{0-v_o}{a}[/tex]

         t = 100/4

         t = 25 s

In conclusion using Newton's second law and the kinematics relations we can find the results for the questions about the forces and the motion of the block are:

    B) the force applied to maintain the system is equilibrium is: F = 0.39 N with an angle of tea = 180º

    C) The maximum force is: F = 24 N

    D) The time to stop the block is: t = 25 s

Learn more about Newton's second law here: brainly.com/question/25545050

Answer:

Explanation:

Do you mean "made" as in the element itself, or "made" as it is extracted from the Earth and refined.

====

The elements originate in the stars.  The fusion reactions in Earth's sun fuse hydrogen and helium atoms to make elements, up to iron.  Larger stars and powerful explosions such as supernova create the larger elements.  Humans, with the use of particle accelerators make even larger elements, nearly all of which are unstable and decay rapidly into smaller elements.  But their creation does offer the perk of naming rights if you can prove it was created, and don't pick a clearly untenable name.

The Fe in stardust from the sun collects in clumps via gravitational forces and, via meteorites, is carried to Earth.  This is the major source for pure iron on the Earth.

Iron has chemical properties that lead to it reacting with other substances (e.g., oxygen) and then becoming concentrated in deposits as a variety of salts  in the Earth's crust, as a result of natural processes.  These deposits are mined and the rock is heated to separate and purify the iron metal.

Answer:

- 30 kW

Explanation:

IDEA:

Power of an object that does work(source) is given by:

[tex] \boxed{ \mathsf{power = \frac{work \: done}{time} }}[/tex]

where work done is mostly shown as the Force applied on an object to Displace it through some distance in the same direction as the Force.

[tex] \boxed{ \mathsf{ work = force \times displacement}}[/tex]

___________________

INFORMATION:

In the question,

The source of power is the crane, while the object is a load of 36000N.

Note, what's given is the force, not the mass. Since, the SI unit of mass is kg and that of Force is Newton(N).

[The weight of the load is represented in Newton, since weight of an object is the amount of Force with which the Earth attracts that object]

I) work done

So,

=> Work = 36000 × 50

= 1,800,000 J

(The SI unit of work is Joules(J)).

___________________

II) power

After getting the amount of work done, now we have to place it in the formula for power.

That is:

[tex] \boxed{ \mathsf{power = \frac{work \: done}{time} }}[/tex]

Note, During calculations, all quantities must be in their SI units.

SI unit for time is Seconds (s)

But the time we have is in minutes.

___________________

Converting time from minutes to Seconds:

1 minute = 60 Seconds.

Hence,

[tex] \implies \mathsf{power = \frac{1800000}{60} } \: [/tex]

=> power = 30,000 W

(SI unit of power is Watts(W))

To write four zeroes with a 3 and W is a lot of effort. So, we can look for simple expressions like kilowatts(kW) that can express bigger quantities in lesser terms.

1000 W = 1 kW

___________________

Direction and sign:

The crane displaces the load in an upward direction (from the term "lifts")

But, the Force is acting downwards, as the weight of the body is always towards the Earth.

Since, the directions of Force and displacement are opposite, a minus takes its place in front of both Work and power.

___________________

Therefore, the final answer will be:

Explanation:

[tex] \rule{999pt}{66646pt}[/tex]

Answer:

density can be written as:

d = F / V  (weight density) or M / V (mass density)

Since F in the first equation can be written as

B = d V where B is the buoyant force and is proportional to the

weight of the liquid displaced

For a given volume the weight of the liquid displaced is proportional to the density and hence the buoyant force

Hi there!

We can begin by solving for the velocity in which the ball was thrown at using the following:

[tex]v_f^2 = v_i^2 + 2ad[/tex]

At the top of the trajectory, the ball's velocity is equal to 0 m/s, so:

[tex]0 = v_i^2 + 2ad\\\\vi^2 = 2ad \\\\[/tex]

'a' = acceleration due to gravity and 'd' is the max height, so:

[tex]v_i^2 = 2(10)(5)\\\\v_i^2 = 10 m/s[/tex]

Now, we can use the same equation to calculate the final speed at 4.5 m. Remember, the acceleration is NEGATIVE in this instance (taking the negative direction to be in the direction of gravity).

[tex]v_f^2 = 10^2 - 2(10)(4.5)[/tex]

[tex]v_f^2 = 10^2 - 2(10)(4.5)\\\\v_f^2 = 100 - 90 \\\\v_f^2 = 10 \\\\v_f = \boxed{3.1 m/s}[/tex]

Answer:

The force of gravity on earth, no matter the object is approximately 9.8 m/ s2 . The reason the crumpled paper hits the ground first is because of air resistance. A crumpled piece of paper has less surface area than an piece of paper that is not crumpled. More surface area means more air resistance.

Answer:

the answer is the rollar coster

Explanation:

because the rollar coster is

The student who did the most work is student 2 with 2500 Joules.

Given the following data:

To determine which of the students did the most work:

Mathematically, the work done by an object is given by the formula;

[tex]Work\;done = Force \times distance[/tex]

For student 1:

[tex]Work\;done = 500 \times 1.2[/tex]

Work done = 600 Joules

For student 2:

[tex]Work\;done = 500 \times 5[/tex]

Work done = 2500 Joules.

Therefore, the student who did the most work is student 2 with 2500 Joules.

Read more: Read more: brainly.com/question/13818347

Answer:student 2 did the most work

Explanation:student 2 did more work because he pushed it up 5 m instead of 1.2.