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
Harman [31]
3 years ago
12

A capacitor is charged to a potential difference of 12v it delivers 40% of its stored energy to a lamp what is the final potenti

al difference across the capacitor
Physics
1 answer:
Korolek [52]3 years ago
6 0
Call the capacitance C. 
<span>Note the energy in a capacitor with voltage V is E =½CV². </span>

<span>Initial energy = ½C(12)² = 72C </span>

<span>40% of energy is delivered, so 60% remains.in the capacitor. </span>
<span>Remaining energy = (60/100) x 72C =43.2C </span>

<span>If the final potential difference is X, the energy stored is ½CX² </span>
<span>½CX² = 43.2C </span>
<span>X² = 2 x 43.2 = 86.4 </span>
<span>X = 9.3V</span>
You might be interested in
A student is about to sled down a hill. He stands on a hill which is 30 meters tall and he weighs 40kg what is his GPE
PolarNik [594]

Answer:

11760J

Explanation:

Given parameters:

Height of hill  = 30m

Weight  = 40kg

Unknown:

Gravitational potential energy  = ?

Solution:

To find the gravitational potential energy, it is the energy due to the position of a body;

     G.PE  = mgh

m is the mass

g is the acceleration due to gravity

h is the height

 Now insert the parameters and solve;

      G.PE = 40 x 9.8 x 30  = 11760J

3 0
3 years ago
Nina is doing a workout where she runs at 50% speed for 3 minutes, 75% speed for 2 minutes, and 100% speed for 30 seconds. This
Dovator [93]
D. Interval training
7 0
2 years ago
Read 2 more answers
What type of circuit is shown?
Roman55 [17]
Open circuit ......fiend do
3 0
3 years ago
Read 2 more answers
You push your couch a distance of 3.9 m across the living room floor with a horizontal force of 220.0 n. the force of friction i
Mrac [35]

The general formula to calculate the work is:

W=Fd \cos \theta

where F is the force, d is the displacement of the couch, and \theta is the angle between the direction of the force and the displacement. Let's apply this formula to the different parts of the problem.


(a) Work done by you: in this case, the force applied is parallel to the displacement of the couch, so \theta=0^{\circ} and \cos \theta=1, therefore the work is just equal to the product between the horizontal force you apply to push the couch and the distance the couch has been moved:

W=Fd=(220.0 N)(3.9 m)=858 J


(b) work done by the frictional force: the frictional force has opposite direction to the displacement, therefore \theta=180^{\circ} and \cos \theta=-1. Therefore, we must include a negative sign when we calculate the work done by the frictional force:

W=-Fd=-(144.0 N)(3.9 m)=-561.6 J


(c) The work done by gravity is zero. In fact, gravity (which points downwards) is perpendicular to the displacement of the couch (which is horizontal), therefore \theta=90^{\circ} and \cos \theta=0: this means

W=0.


(d) Work done by the net force:

The net force is the difference between the horizontal force applied by you and the frictional force:

F=220 N-144 N=76 N

And the net force is in the same direction of the displacement, so \theta=0^{\circ} and \cos \theta=1 and the work done is

W=Fd=(76 N)(3.9 m)=296.4 J


4 0
4 years ago
(Double points) A mechanic used a wrench 0.6 meters long to loosen rusted lug nuts on a truck wheel. By standing on the end of t
Korolek [52]

Answer:

Torque, \tau=588\ N-m

Explanation:

It is given that,

Length of the wrench, l = 0.6 m

Mass of the wrench, m = 100 kg

We know that the torque applied by mechanic is given by :

\tau=Fl

\tau=mgl

\tau=100\times 9.8\times 0.6

\tau=588\ N-m

So, the torque applied by the mechanic is 588 N-m. Hence, this is the required solution.

3 0
3 years ago
Other questions:
  • You are playing catch with a friend in a moving train. When you toss the ball in the direction the train is moving, how does the
    5·1 answer
  • Which of the the following distance vs time graphs represents an object the is moving at constant non zero velocity
    12·1 answer
  • The spaceship Intergalactica lands on the surface of the uninhabited Pink Planet, which orbits a rather average star in the dist
    8·1 answer
  • The policeman also watched a truck that was sitting at the red light. When the light turned green, the truck slowly started movi
    5·2 answers
  • An elevator is moving upward at 0.91 m/s when it experiences an acceleration 0.31 m/s2 downward, over a distance of 0.61 m. What
    6·1 answer
  • 8. Approximately how many hours a day are spent in school and doing homework?
    7·1 answer
  • Suppose you look out the window of a skyscraper and see someone throw a tomato downward from above your window. your window is a
    8·1 answer
  • What is the change in momentum of a 1000kg car moving from 1 m/s to 8m/s
    8·1 answer
  • The drawing shows a top view of a door that is free to rotate about an axis of rotation that is perpendicular to the screen. Fin
    8·1 answer
  • Facts about conolizing into mars?​
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!