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
ss7ja [257]
3 years ago
13

How much power is needed to lift a 20-kg object to a height of 4.0 m in 2.5 seconds?

Physics
1 answer:
4vir4ik [10]3 years ago
5 0

Answer:

313.92w

Explanation:

Formula for power:

P=W/∆t = Fv

Givens:

m=20kg

∆y=4.0m

∆t=2.5s

a=9.81m/s²

In order to find power, we first need to solve for work.

W=Fd (force*displacement), f=mg

W=mg∆y

W=(20kg)(9.81m/s²)(4.0m)

W=784.8J

P=W/∆t

P=784.8J/2.5s

P=313.92 watts

You might be interested in
Why is Energy not created nor destroyed?<br> (Need the answer ASAP!!)
eduard

Since both heat and work can be measured and quantified, this is the same as saying that any change in the energy of a system must result in a corresponding change in the energy of the surroundings outside the system. In other words, energy cannot be created or destroyed.

4 0
3 years ago
2. Four resistors of 2 ohm each are connected first in series and then in parallel with a battery.Find the ratio of electric cur
Serjik [45]

Answer:

Ratio of series current to parallel

= 1 : 8

Explanation:

Total resistance Rt

For series, Rt = 2+2+2+2 = 4ohms

For parallel, 1/Rt = 1/2 + 1/2 + 1/2 + 1/2

1/Rt = 4/2, Rt = 2/4 ohms.

If we use a 1V battery, then,

I = V/Rt

I = 1/4 = 0.25 ampere for series arrangement.

I = 1/0.5 = 2 ohms.

Ratio of current of series to parallel = 0.25 : 2

= 1 : 8

4 0
3 years ago
Read 2 more answers
A parallel plate capacitor with air between the plates has a potential difference of 71.0 V. Determine the potential difference
Gwar [14]

Answer:

15.8 V

Explanation:

The relationship between capacitance and potential difference across a capacitor is:

q=CV

where

q is the charge stored on the capacitor

C is the capacitance

V is the potential difference

Here we call C and V the initial capacitance and potential difference across the capacitor, so that the initial charge stored is q.

Later, a dielectric material is inserted between the two plates, so the capacitance changes according to

C'=kC

where k is the dielectric constant of the material. As a result, the potential difference will change (V'). Since the charge stored by the capacitor remains constant,

q=C'V'

So we can combine the two equations:

CV=CV'\\CV=(kC)V'\\V'=\frac{V}{k}

and since we have

V = 71.0 V

k = 4.50

We find the new potential difference:

V'=\frac{71.0}{4.50}=15.8 V

6 0
3 years ago
PSYCHOLOGY. neurons communicate with each other through ____
Alex787 [66]

Answer:

B. Nueral Receptors

3 0
4 years ago
Two particles are moving along the x axis. Particle 1 has a mass m₁ and a velocity v₁ = +4.7 m/s. Particle 2 has a mass m₂ and a
nirvana33 [79]

Answer:

m₁ / m₂ = 1.3

Explanation:

We can work this problem with the moment, the system is formed by the two particles

The moment is conserved, to simulate the system the particles initially move with a moment and suppose a shock where the particular that, without speed, this determines that if you center, you should be stationary, which creates a moment equal to zero

    p₀o = m₁ v₁ + m₂ v₂

    pf = 0

    m₁ v₁ + m₂ v₂ = 0

    m₁ / m₂ = -v₂ / v₁

    m₁ / m₂=  - (-6.2) / 4.7

     m₁ / m₂ = 1.3

Another way to solve this exercise is to use the mass center relationship

    Xcm = 1/M    (m₁ x₁ + m₂ x₂)

We derive from time

   Vcm = 1/M   (m₁ v₁ + m₂v₂)

As they say the velocity of the center of zero masses

    0 = 1/M   (m₁ v₁ + m₂v₂)

   m₁ v₁ + m₂v₂ = 0

    m₁ / m₂ = -v₂ / v₁

   m₁ / m₂ = 1.3

4 0
3 years ago
Other questions:
  • Given this measurement 2642 ft, how many significant figures are there?
    6·1 answer
  • A 1.30 kg skateboard is coasting along the pavement at a speed of 6.64 m/s when a 0.680 kg cat drops from a tree vertically down
    5·1 answer
  • The cheetah is considered the fastest running animal in the world. Cheetahs can accelerate to a speed of 21.7 m/s in 2.50 s and
    13·1 answer
  • A CD-ROM is a compact disk that
    12·1 answer
  • How the relative motion and relative position of the Sun, Earth and Moon affect the seasons, phases of the moon and eclipses?
    9·1 answer
  • when a light bulb is turned on electrical energy is transformed into two other types of energy. What are they and support your a
    13·1 answer
  • A car is travelling at a constant speed of 26.5 m/s. Its tires have a radius of 72 cm. If the car slows down at a constant rate
    7·1 answer
  • Willing to give out brainliest... A vat of ethyl alcohol expands by 0.00823 m^ 3 when the temperature is raised by 44.8 °C . Wha
    8·1 answer
  • The formula v=fλ describes how sound can change. Please explain what these components are, and how they affect one another.
    5·1 answer
  • True or False: There is no object that can travel faster than the speed of light.
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!