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
Pepsi [2]
3 years ago
9

A 7.40-kg object initially has 347 J of gravitational potential energy. Then an elevator lifts the object a distance of 20.6 m a

bove its previous position. How much work did the elevator perform on the object?
Physics
1 answer:
storchak [24]3 years ago
6 0

Answer:

W = 1493.9 J = 1.49 KJ

Explanation:

The work done by the elevator on the object will be equal to the gain in is potential energy:

W = ΔP.E

W = mgΔh

where,

W = Work = ?

m = mass of object = 7.4 kg

g = 9.8 m/s²

Δh = gain in height = 20.6 m

Therefore,

W = (7.4 kg)(9.8 m/s²)(20.6 m)

<u>W = 1493.9 J = 1.49 KJ</u>

You might be interested in
Two masses —m1 and m2— are connected by light cables to the perimeters of two cylinders of radii r1 and r2 respectively, as show
Aleksandr [31]

Answer:

Part a)

Mass of m2 is given as

m_2 = \frac{20}{3} kg

Part b)

Angular acceleration is given as

\alpha = 1.96 rad/s^2

Part c)

Tension in the rope is given as

T = 176.6 N

Explanation:

Part a)

When m1 and m2 both connected to the cylinder then the system is at rest

so we can use torque balance here

m_1g r_1 = m_2 g r_2

20 g(0.5) = m_2 g(1.5)

10 = 1.5 m_2

m_2 = \frac{20}{3} kg

Part b)

When block m_2 is removed then system becomes unstable

so force equation of mass m1

m_1g - T = m_1 a

also we have

T r_1 = I\alpha

now we have

m_1g = \frac{I a}{r_1^2} + m_1 a

a = \frac{m_1g}{\frac{I}{r_1^2} + m_1}

a = \frac{20 (9.81)}{\frac{45}{0.5^2} + 20}

a = 0.981 m/s^2

so angular acceleration is given as

\alpha = \frac{a}{r_1}

\alpha = \frac{0.981}{0.5}

\alpha = 1.96 rad/s^2

Part c)

Tension in the rope is given as

T = \frac{I\alpha}{r_1}

T = \frac{45 (1.96)}{0.5}

T = 176.6 N

7 0
3 years ago
State the laws of vibration of a stringed Instrument​
olchik [2.2K]
If the length and linear density are constant, the frequency is directly proportional to the square root of the tension.
7 0
3 years ago
When the thermal energy of a material decreases, _____.
Pani-rosa [81]
The surrounding environment cool off is the answer
8 0
3 years ago
Read 2 more answers
Please Help!!!!
IgorLugansk [536]
C. Chemical Energy is transformed to light energy and heat energy. The heat energy is keeping you warm and light energy is giving you the light you need to be able to read the book.
8 0
3 years ago
Read 2 more answers
The metric unit of force is _____. kg kg/cm3 kg/cm2 N
ioda

The metric unit of force is Newton or N. The Newton unit is also equal to kilogram per meter per second squared. The Newton name came from the late physicist Isaac Newton. It is also based on the second law of motion.

8 0
3 years ago
Read 2 more answers
Other questions:
  • A spinning ice skater on extremely smooth ice is able to control the rate at which she rotates by pulling in her arms. Which of
    9·1 answer
  • pulling one of the balls away from the other. To pull a ball away, click on the ball and drag it. What happens to the force arro
    11·2 answers
  • Sodium chloride, NaCl, is formed when a sodium atom transfers its electron to a chlorine atom. The difference in charge between
    5·2 answers
  • Rock can be weathered and eroded in the rock cycle. What might happen with the resulting rock particles? A. New rock is formed f
    8·2 answers
  • Suppose you're on a hot air balloon ride, carrying a buzzer that emits a sound of frequency f. If you accidentally drop the buzz
    15·1 answer
  • When saturated air is cooled what happens to its dew point
    12·1 answer
  • In a longitudinal wave, amplitude can be measured from the
    15·1 answer
  • How do you know when to use each equations of motion while solving numericals? Please help as soon as possible .
    8·1 answer
  • Un tren de alta velocidad (TAV) o tren bala es aquel que alcanza velocidades iguales o superiores a 200 km/h. La energía que tie
    9·1 answer
  • What causes all landforms to take shape and develop? (SCIENCE)
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!