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
Alenkinab [10]
3 years ago
14

Help with these questions please , 15 PTS & brainliest

Physics
1 answer:
myrzilka [38]3 years ago
6 0

For these two questions, first you need to know that the voltage across each branch of a parallel circuit is the same.

So, for Q5, we can first find out the voltage across R₂ by V=IR.

Voltage across R₂ = 2.5 × 8 = 20V

Since R₂ and R₃ are in parallel circuit, their voltage should be the same. Thus, voltage across R₃ is 20V.

So, by V=IR,

current of R₃ = \frac{20}{4} = 5A

Q6. voltage across R₁ = 2 × 4 = 8V

∴voltage across R₂ = 8V

current of R₂ = \frac{8}{8} = 1A

<h3><u>Alternative method</u></h3>

From these two examples, you can find out that the current of each branch of the parallel circuit is inversely proportional to the resistance of the branch.

ie. for Q5,

\frac{R2}{R3} = \frac{I3}{I2}

\frac{8}{4} = \frac{I3}{2.5}

I₃ = 5A

Q6. \frac{R1}{R2} = \frac{I2}{I1}

\frac{4}{8} = \frac{I2}{2}

I₂ = 1A

You might be interested in
20. Consider a model steel bridge that is 1/100 the exact scale of the real bridge that is to be built. a. If the model bridge w
Veseljchak [2.6K]
The model bridge captures all the structural attributes of the real bridge, at a reduced scale.

Part a.
Note that volume is proportional to the cube of length. Therefore the actual bridge will have 100^3 = 10^6 times the mass of the model bridge.

Because the model bridge weighs 50 N, the real bridge weighs
(50 N)*10^6 = 50 MN.

Part b.
The model bridge matches the structural characteristics of the actual bridge.
Therefore the real bridge will not sag either.
6 0
3 years ago
A ball is dropped from rest at height of 20m. If it loses 25% of its kinetic energy when it strikes the ground. What is the heig
victus00 [196]

Answer:

15 meters

Explanation:

The inicial energy of the ball is just potencial energy, and its value is:

E = m * g * h = m * g * 20,

where m is the ball mass, and g is the value of gravity.

In the moment that the ball strickes the ground, all potencial energy transformed into kinetic energy, and 25% of this energy is lost, so the total energy at this moment will be:

E' = 0.75 * E = 0.75 * m * g * 20 = 15*m*g

This kinetic energy will make the ball goes up again, and at the maximum height, all kinetic energy is transformed back into potencial energy.

So, as the mass and the gravity are constants, we can calculate the height the ball will reach:

E' = m*g*h = 15*m*g -> h = 15 meters

6 0
3 years ago
Un cable está tendido sobre dos postes colocados con una separación de 10 m. A la mitad del cable se cuelga un letrero que provo
lisabon 2012 [21]

Answer:

El peso del cartel es 397,97 N

Explanation:

La tensión dada en cada segmento del cable = 2000 N

El desplazamiento vertical del cable = 50 cm = 0,5 m

La distancia entre los polos = 10 m

La posición del letrero en el cable = En el medio = 5

El ángulo de inclinación del cable a la vertical = tan⁻¹ (0.5 / 5) = 5.71 °

El peso del letrero = La suma del componente vertical de la tensión en cada lado del letrero

El peso del signo = 2000 × sin (5.71 grados) + 2000 × sin (5.71 grados) = 397.97 N

El peso del signo = 397,97 N.

8 0
3 years ago
What I Know True or False. Read each statement carefully. Identify whether the statement is true or false. Write your answer on
timofeeve [1]

Answer:

1. False

2. True

3. True

4. True

5. True

6. False

7. True

8. False

9. False

10. True

11. True

12. True

13. True

14. True

15. True

7 0
3 years ago
Read 2 more answers
izes water on the surface of Mars? a. Billions of years ago there were lakes and rivers on the surface of Mars, but none exist t
Tanzania [10]

Answer:

The answer is a.

Explanation: Billions of years ago, there were lakes and rivers in the surface of mars because mars had a denser atmosphere and higher surface temperatures which allowed a vast amount of liquid water on the surface. Recently, most of the water on mars today exist as ice.

6 0
3 years ago
Other questions:
  • A 13-cm-diameter cd has a mass of 25 g . part a what is the cd's moment of inertia for rotation about a perpendicular axis throu
    5·2 answers
  • What will be the time period of simple pendulum at the center of earth​
    14·1 answer
  • the weight of an object on a planet depends not only on its mass, but also on its distance from the planets center. This table l
    11·1 answer
  • A closed-end manometer was attached to a vessel containing argon. The difference in the mercury levels in the two arms of the ma
    5·1 answer
  • If a car is traveling 60 mph, its tires may have an rpm of 840. How many revolutions do the car’s tires make in one second?
    6·1 answer
  • A golf ball rolls off a horizontal cliff with an initial speed of 11.4 m/s. The ball falls a vertical distance of 17.7 m into a
    6·1 answer
  • 18.How much momentum will a dump-bell of mass 10 kg transfer to the floor if it falls from a height.of 80 cm ? Take its downward
    13·2 answers
  • Why do fishermen like fishing during a full moon?
    11·1 answer
  • Where would you expect light waves to move faster?
    6·2 answers
  • A weather balloon has a volume of 35 L at sea level (1.0 atm). After the balloon is released it rises to where the air pressure
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!