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
butalik [34]
3 years ago
13

Which of the following describes the efficiency of real machines?

Physics
2 answers:
Mariulka [41]3 years ago
4 0

Are you sure! Becuase I dont want to get this one wrong!



Leokris [45]3 years ago
3 0
Choice-B is the true one.
You might be interested in
A 72.8-kg swimmer is standing on a stationary 265-kg floating raft. The swimmer then runs off the raft horizontally with a veloc
nalin [4]

Answer:

-1.43 m/s relative to the shore

Explanation:

Total momentum must be conserved before and after the run. Since they were both stationary before, their total speed, and momentum, is 0, so is the total momentum after the run off:

m_sv_s + m_rv_r = 0

where m_s = 72.8, m_r = 265 are the mass of the swimmer and raft, respectively. v_s = 5.21 m/s, v_r are the velocities of the swimmer and the raft after the run, respectively. We can solve for v_r

265v_r + 72.8*5.21 = 0

v_b = -72.8*5.21/265 = -1.43 m/s

So the recoil velocity that the raft would have is -1.43 m/s after the swimmer runs off, relative to the shore

7 0
2 years ago
How is the magnetic force on a particle moving in a magnetic field different from gravitational and electric forces.
harina [27]

Answer:

The magnetic force on a free moving charge depends on the velocity of the charge and the magnetic field, direction of the force is given by the right hand rule. While gravitational depends on the mass and distance of the moving particle and electric forces depends on the magnitude of the charge and distance of separation.

Explanation:

The magnetic force on a free moving charge depends on the velocity of the charge and the magnetic field and direction of the force is given by the right hand rule. While gravitational depends on the mass and distance of the moving particle and electric forces depends on the magnitude of the charge and distance of separation.

The magnetic force is given by the charge times the vector product of velocity and magnetic field. While gravitational force is given by the square of the particle mass divided by the square its distance of separation. Also electric forces is given by the square of the charge magnitude divided by the square its distance separation.

4 0
2 years ago
¿Qué ocurre como consecuencia de las corrientes de convección en la astenosfera?
Vladimir [108]

Respuesta:En la astenosfera existen lentos movimientos de convección que explican la deriva continental. Además, el basalto de la astenosfera fluye por extrusión a lo largo de las dorsales oceánicas, lo cual hace que se renueve y expanda constantemente el fondo oceánico. :D

6 0
3 years ago
What is the approximate terminal velocity of a sky diver before the parachute opens
anzhelika [568]

Answer:

The approximate terminal velocity of a sky diver before the parachute opens is 320 km/h.

Explanation:

  • The terminal velocity is the maximum magnitude of velocity that is attained by the diver when he or she falls in the air.
  • The terminal velocity of the person diving in air before opening parachute is 320 km/h that means the velocity when the person is experiencing free fall is 320 km/h.
  • During terminal velocity, we can represent mathematical equation as;

                           Buoyancy force + drag force = Gravity

6 0
3 years ago
The heating element in a kettle behaves like a resistor. A particular kettle needs to operate at 230 V, with a power of 1500 W.
dedylja [7]

Answer:

R = 35.27 Ohms

Explanation:

Given the following data;

Voltage = 230V

Power = 1500W

To find the resistance, R;

Power = V²/R

Where:

V is the voltage measured in volts.

R is the resistance measured in ohms.

Substituting into the equation, we have;

1500 = 230²/R

Cross-multiplying, we have;

1500R = 52900

R = 52900/1500

R = 35.27 Ohms.

Therefore, the resistance which the heating element needs to have​ is 35.27 Ohms.

4 0
2 years ago
Other questions:
  • A ____ is the time required for one half of the nuclei in a radio- ____ isotope to decay.
    9·1 answer
  • The astronomical unit (AU) is defined as the mean center-to-center distance from Earth to the Sun, namely 1.496x10^(11) m. The p
    13·1 answer
  • Is<br>pressure<br>and<br>electric<br>charge<br>a vector<br>quantity? Explain.​
    5·1 answer
  • A ________ ion is created when an electron is removed.
    12·1 answer
  • What is the magnitude of the velocity after it hits the ground?
    10·1 answer
  • The hair dryer has a plastic case so there is no need for an earth wire connection in the plug ,explain why the hair dryer is st
    7·1 answer
  • Compared to a human, what is similar about how blue whales organism gets molecules from food and air?
    10·2 answers
  • The data table for the decomposition reaction of hydrogen peroxide H2 O2 shows how the reaction rate changes over time which sta
    15·2 answers
  • O((&gt;ω&lt; ))oo((&gt;ω&lt; ))oo((&gt;ω&lt; ))oo((&gt;ω&lt; ))oo((&gt;ω&lt; ))o
    5·1 answer
  • Five locations are marked on the world map. which location is most prone to hurricanes? five locations are marked on the world m
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!