Answer:

**Complete Question **

A power supply has an open-circuit voltage of 40.0 V and an internal resistance of 2.00 . It is used to charge two storage batteries connected in series, each having an emf of 6.00 V and internal resistance of 0.300 . If the charging current is to be 4.00 A, (a) what additional resistance should be added in series? At what rate does the internal energy increase in (b) the supply, (c) in the batteries, and (d) in the added series resistance? (e) At what rate does the chemical energy increase in the batteries?

**Answer:**

**a**

The additional resistance is

**b**

The rate at which internal energy increase at the supply is

**c**

The rate at which internal energy increase in the battery is

**d**

The rate at which internal energy increase in the added series resistance is

**e**

the increase rate of the chemically energy in the battery is

**Explanation:**

From the question we are told that

The open circuit voltage is

The internal resistance is

The emf of each battery is

The internal resistance of the battery is

The charging current is

Let assume the the additional resistance to to added to the circuit is

So this implies that

The total resistance in the circuit is

Substituting values

And the difference in potential in the circuit is

=>

Now according to ohm's law

Substituting values

Making the subject of the formula

So

The increase rate of internal energy at the supply is mathematically represented as

Substituting values

The increase rate of internal energy at the batteries is mathematically represented as

Substituting values

The increase rate of internal energy at the added series resistance is mathematically represented as

Substituting values

Generally the increase rate of the chemically energy in the battery is mathematically represented as

Substituting values

Why is it important to select a coordinate system when studying motion?

A rescue helicopter is hovering over a person whose boat has sunk. One of the rescuers throws a life preserver straight down to the victim with an initial velocity of 1.50 m/s and observes that it takes 1.2 s to reach the water. How high above the water was the preserver released? Note that the downdraft of the helicopter reduces the effects of air resistance on the falling life preserver, so that an acceleration equal to that of gravity is reasonable. Round your answer to the nearest whole number.

What is the pH of a solution with a hydrogen ion concentration of 2.0x10^3.(Use 3 digits)

Point charge 3.5 μC is located at x = 0, y = 0.30 m, point charge -3.5 μC is located at x = 0 y = -0.30 m. What are (a)the magnitude and (b)direction of the total electric force that these charges exert on a third point charge Q = 4.0 μC at x = 0.40 m, y = 0?

If half the kinetic energy of the initially moving object (m1m1) is transferred to the other object (m2m2), what is the ratio of their masses? Express your answers using three significant figures separated by a comma.

A rescue helicopter is hovering over a person whose boat has sunk. One of the rescuers throws a life preserver straight down to the victim with an initial velocity of 1.50 m/s and observes that it takes 1.2 s to reach the water. How high above the water was the preserver released? Note that the downdraft of the helicopter reduces the effects of air resistance on the falling life preserver, so that an acceleration equal to that of gravity is reasonable. Round your answer to the nearest whole number.

What is the pH of a solution with a hydrogen ion concentration of 2.0x10^3.(Use 3 digits)

Point charge 3.5 μC is located at x = 0, y = 0.30 m, point charge -3.5 μC is located at x = 0 y = -0.30 m. What are (a)the magnitude and (b)direction of the total electric force that these charges exert on a third point charge Q = 4.0 μC at x = 0.40 m, y = 0?

If half the kinetic energy of the initially moving object (m1m1) is transferred to the other object (m2m2), what is the ratio of their masses? Express your answers using three significant figures separated by a comma.

**Answer:12.11 m**

**Explanation:**

Given

Bug speed =1.7 m/s

Let mass of bug is m

mass of rod 16m

maximum angle turned by rod is 7^{\circ}[/tex]

From Energy conservation

kinetic energy of bug =Gain in potential energy of rod

L=12.11 m

**Answer:**

It will take 313.376 sec to raise temperature to boiling point

**Explanation:**

We have given that potential difference V = 120 Volt

Current i = 4.50 A

So resistance

Heat flow in resistor will be equal to

It is given that this heat is used for boiling the water

Mass of the water = 0.525 kg = 525 gram

Specific heat of water 4.186 J/gram/°C

Initial temperature is given as 23°C

Boiling temperature of water = 100°C

So change in temperature = 100-23 = 77°C

Heat required to raise the temperature of water

So

t = 313.376 sec

So it will take 313.376 sec to raise temperature to boiling point

**Answer:**

**Explanation:**

Voltage, V = 120 V

Current, i = 4.5 A

mass of water, m = 0.525 kg

initial temperature of water, T1 = 23°C

Final temperature of water, T2 = 100 °C

specific heat of water, c = 4.18 x 1000 J/kg °c

let the time taken is t.

Heat given by the heater = heat gain by the water

V x i x t = m x c x (T2 - T1)

120 x 4.5 x t = 0.525 x 4.18 x 1000 x (100 - 23)

540 t = 47701.5

t = 88.34 s

**Explanation:**

It is given that,

Mass of the tennis ball,

Initial speed of tennis ball,

Mass of ball,

Initial speed of ball,

In case of elastic collision, the momentum remains conserved. The momentum equation is given by :

are final speed of tennis ball and the ball respectively.

..............(1)

We know that the coefficient of restitution is equal to 1. It is given by :

.................(2)

On solving equation (1) and (2) to find the values of velocities after collision.

**So, the speed of both balls are 5.28 m/s and 3 m/s respectively. Hence, this is the required solution.**

**Answer:**

Emf induced in the loop is 0.02V

**Explanation:**

To get the emf of induced loop, we have to use faraday's law

ε = - dΦ/dt

To get the flux, we use;

Φ = BA cos(θ)

B = The uniform magnetic field

A = Area of rectangular loop

θ = angle between magnetic field and normal to the plane of loop

substitute the flux equation (Φ) into the faraday's equation

we have ε = - d(BA cos(θ)) / dt

ε = BA sinθ dθ/dt

from the question;B = 0.18T, A=0.15m2, θ = π/2 ,dθ/dt = 0.75rad/s

Our equation will now look like this;

ε = (0.18T) (0.15m2) (sin(π/2)) (0.75rad/s)

ε = 0.02V

the mass would be 75kg

think the sound frequencies that dogs can

hear compare to the frequencies that humans

can hear?

**Dogs** can hear **sounds** at higher frequencies than humans. The range of sound frequencies that dogs can hear is approximately 40 Hz to 60,000 Hz, while the range for humans is 20 Hz to 20,000 Hz. This means that dogs can hear ultrasonic sounds that are beyond the range of human hearing.

In terms of physics, **sound** is a vibration that travels through a transmission medium like a gas, liquid, or solid as an acoustic **wave**.

**Sound** is the reception of these waves and the brain's perception of them in terms of human physiology and psychology. **Dogs** have the ability to hear ultrasonic sounds that are audible only to them.

Learn more about **sound** on:

#SPJ1