1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Nat2105 [25]
2 years ago
15

A crane lifts an air conditioner to the top of a building. If the building is 12 m high, and the air conditioner has a mass of 2

00 kg, how much work did the crane do to lift it? (Hint: the force the crane exerts is equal to the weight of the air conditioner)
Physics
1 answer:
Pepsi [2]2 years ago
8 0

Work needed = 23,520 J

<h3> Further explanation </h3>

Given

height = 12 m

mass = 200 kg

Required

work needed by the crane

Solution

Work is the transfer of energy caused by the force acting on a moving object  

Work is the product of force with the displacement of objects.  

Can be formulated  

W = F x d  

W = Work, J, Nm  

F = Force, N  

d = distance, m  

F = m x g

Input the value :

W = mgd

W = 200 kg x 9.8 m/s²x12 m

W = 23520 J

You might be interested in
A solar flare is a sudden, rapid, and intense change in the brightness of the sun. Which of these is most
nikdorinn [45]

Answer:

electronic communications may be disrupted

Explanation:

Solar Flares: They occur when the magnetic field lines carrying charged particle entangle and reorganize over the photosphere of the Sun. In these flares charged particles leave the surface of the Sun to travel outwards.

If these flares are directed towards Earth, they will interact with anything related to electricity and magnetism. Out of the given options third option is correct as the electronic communication will be disrupted. If the flares are strong a complete power blackout may occur and that would disrupt all the communication channel and power transmission. Such events have occurred in the past as well.

8 0
3 years ago
A ball of mass 0.120 kg is dropped from rest from a height of 1.25 m. It rebounds from the floor to reach a height of 0.820 m. W
Vikentia [17]

Answer:

1.0752 kgm/s

Explanation:

Considering when the drop was dropped from rest from a height,

mass of the ball, m = 0.120 kg

height, h = - 1.25 m

the initial velocity, u = 0 m/s

the acceleration due to gravity, g = - 9.8 m/s²

From equation of motion

                            V^{2} = U^{2} + 2gh

Substituting the values,

                             V^{2} = 0^{2} + 2(-9.8 m/s^{2})(-1.25 m)

                             V^{2} = 24.5 m/s

                             V = \sqrt{24.5} \ m/s

                             V = 4.95 \ m/s

                            V = ± 4.95 m/s

                            V = - 4.95 m/s

Since the ball is moving downward, the final velocity of the ball when it hits the floor is  V = - 4.95 m/s  

Considering when the ball rebounds from the floor,

assume the mass of the ball still remain, m = 0.120 kg

height, h = 0.820 m

the final velocity, v = 0 m/s  

the acceleration due to gravity, g = - 9.8 m/s²

From equation of motion

                            V^{2} = U^{2} + 2gh

Substituting the values,

                            0^{2} = U^{2} + 2(-9.8 m/s^{2})(0.820 m)

                            0 = U^{2} - 16.072 m/s

                            U^{2} = 16.072 m/s

                            U = \sqrt{16.072} \ m/s

                           U = ± 4.01 m/s

                          U = + 4.01 m/s

Since the ball is moving upward, the initial velocity of the ball from the bounce from the floor is  U = + 4.01 m/s                        

From Newton's second law of motion, applied force is directly proportional to the rate of change in momentum.

                            F = \frac{mv - mu}{t}

                          F.t = m(v - u)

       ⇒      Impulse = Change in momentum

To calculate the impulse, the moment before the ball hits the ground will be the initial momentum while the moment the ball rebounces will be the final velocity,                        

          ∴          F.t = 0.120  kg(4.01  m/s - (-4.95  m/s) )

                      F.t = 0.120  kg(4.01  m/s + 4.95  m/s) )

                      F.t = 0.120  kg × 8.96  m/s

                      Impulse  = 1.0752 kgm/s

The impulse given to the ball by the floor is 1.0752 kgm/s

                             

6 0
3 years ago
A 3.91 kg cart is moving at 5.7 m/s when it collides with a 4 kg cart which was at rest. They collide and stick together.
Nesterboy [21]

Answer:

<em>The velocity after the collision is 2.82 m/s</em>

Explanation:

<u>Law Of Conservation Of Linear Momentum </u>

It states the total momentum of a system of bodies is conserved unless an external force is applied to it. The formula for the momentum of a body with mass m and speed v is  

P=mv.  

If we have a system of two bodies, then the total momentum is the sum of the individual momentums:

P=m_1v_1+m_2v_2

If a collision occurs and the velocities change to v', the final momentum is:

P'=m_1v'_1+m_2v'_2

Since the total momentum is conserved, then:

P = P'

Or, equivalently:

m_1v_1+m_2v_2=m_1v'_1+m_2v'_2

If both masses stick together after the collision at a common speed v', then:

m_1v_1+m_2v_2=(m_1+m_2)v'

The common velocity after this situation is:

\displaystyle v'=\frac{m_1v_1+m_2v_2}{m_1+m_2}

There is an m1=3.91 kg car moving at v1=5.7 m/s that collides with an m2=4 kg cart that was at rest v2=0.

After the collision, both cars stick together. Let's compute the common speed after that:

\displaystyle v'=\frac{3.91*5.7+4*0}{3.91+4}

\displaystyle v'=\frac{22.287}{7.91}

\boxed{v' = 2.82\ m/s}

The velocity after the collision is 2.82 m/s

6 0
2 years ago
Waves move fastest in
JulijaS [17]
Liquids<span> are not </span>packed<span> as tightly as </span>solids<span>. And gases are very loosely </span>packed<span>. The spacing of the molecules enables </span>sound<span> to travel much faster through a </span>solid<span> than a gas. </span>Sound<span> travels about four times faster and farther in water than it does in air.</span>
4 0
3 years ago
Read 2 more answers
When you lift an object, you add the energy of lifting to the object.<br> Tor F
PtichkaEL [24]

It's true, when we lift an object we add energy to it.

because, when we lift an object by applying force , the object attains a height and hence the energy gets stored in it, in the form gravitational potential energy .

6 0
3 years ago
Other questions:
  • (WILL MARK BRAINLIEST AND 22pts) As the earth travels around the sun, the sun is always at one focus of an ellipse. What's at th
    12·2 answers
  • A simply supported beam, 4" wide, 6" deep, and 16 ft. long carries a uniformly distributed load of 300 lb/ft (a) compute the she
    14·1 answer
  • What is the work done by 20 Newton force applied at an angle of 45.0° to move a box a horizontal distance of 40 meters
    5·2 answers
  • An electron moving at 2.97×103 m/s in a 1.25 T magnetic field experiences a magnetic force of 1.40×10−16 N . What angle (in degr
    8·1 answer
  • Three arrows are shot horizontally. They have left the bow and are traveling parallel to the ground. Air resistance is negligibl
    5·1 answer
  • Describe how two isotopes of nitrogen differ from two nitrogen ions?
    8·1 answer
  • Question : Is it possible for heat to transfer from T3 to T1 and why?
    14·1 answer
  • If the population runs out of food after 6 hours, what would most likely happen to the graph line between 8 and 10 hours?
    12·2 answers
  • Plz help me find the answers
    5·2 answers
  • Select the correct answer. Using the right hand rule, what do the three numbered vectors represent in the diagram below? A. 1) f
    11·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!