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1 year ago

1. Describe the methods by which an electric potential develops in primary cells and dry cells.

Physics

1 answer:

Andreyy891 year ago

6 0

Answer:

In primary cells, an electric potential develops through chemical action between the plates within the cell. Positively charged ions of zinc enter the acid and free electrons released from zinc atoms collect on the zinc plate, which results in a negative charge. At the same time, positively charged ions of hydrogen from the acid remove free electrons from the copper plate, which becomes positively charged. Through a conducting material connecting the plates, free electrons move from the zinc plate to the copper plate as long as the chemical reaction lasts.

Dry cells also develop electric potential via chemical actions within the cell. Free electrons removed from the carbon rod collect on a zinc can. The rod exhibits a positive charge and the can becomes negatively charged; this allows for an electric potential to develop between these two items. Through a conducting material connecting the can to the rod, free electrons move from the can to the rod as long as the conducting path exists.

Electric generators develop an electric potential via magnetic induction. Moving a conducting rod through a magnetic field that exists between the poles of a horseshoe magnet causes an electric potential to be set up in the rod. Free electrons move through this rod from one end to the other for as long as movement of the rod is maintained. The direction of this movement depends on whether the rod is moved across the lines of force in the magnetic field in either the opposite direction or the same direction. Generators usually consist of multiple conductors mounted on a cylinder that rotates in a magnetic field.

Thermocouples utilize heat to develop an electric potential. Two strips of different metals are connected at one end to form a junction and the other ends are kept apart. A heat source is applied to the junction; this causes each metal strip’s temperature to rise at the junction. The free ends aren’t as hot and electric charges are produced at these free ends. Because the strips consist of different materials, there's a difference of potential between these free ends; when connected by a conducting wire, the electrons can move through the pathway. The voltage that's produced will become greater as the difference in temperature between the free ends and the junction increases.

a. Increase

b. Decrease

c. Decrease

Since 1 Btu = 0.293 Wh, dividing the given amount of Wh by 0.293 will convert this amount into Btu. Therefore, 0.8 ÷ 0.293 = 2.73 Btu

365 days × 10 hours × 40 W = 146,000 Wh or 146 kWh

Explanation:

Penn Foster

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Somewhere in the vast flat tundra of planet Tehar, a projectile is launched from the ground at an angle of 60 degrees. It reache

Nina [5.8K]

Answer:

R = 0.0503 m

Explanation:

This is a projectile launching exercise, to find the range we can use the equation

R = v₀² sin 2θ / g

How we know the maximum height

$v_{f}$ ² = $v_{oy}$ ² - 2 g y

$v_{f}$ = 0

$v_{oy}$ = √ 2 g y

$v_{oy}$ = √ 2 9.8 / 15

$v_{oy}$ = 1.14 m / s

Let's use trigonometry to find the speed

sin θ = $v_{oy}$ / vo

vo = $v_{oy}$ / sin θ

vo = 1.14 / sin 60

vo = 1.32 m / s

We calculate the range with the first equation

R = 1.32² sin(2 60) / 30

R = 0.0503 m

3 0

1 year ago

A shear wave (S wave) is a type of seismic _________ that shakes the ground back and forth perpendicular to the direction the wa

Zepler [3.9K]

Body waves

Explanation:

A shear wave(S-wave) is a type of seismic body waves that shakes the ground back and forth perpendicular to the direction the wave is moving.

Seismic waves are elastic waves usually generated when there is a disturbance within the earth.
There are two types of seismic waves:

Surface waves

Body waves

Body waves travel within the earth and they cause disturbances there. P and S waves are the two types of body waves that we have.
Surface waves travels on the earth surface. They are the love and rayleigh waves. They are the ones that cause destruction on the earth surface during an earthquake.

Learn more:

Earthquake brainly.com/question/6520403

#learnwithBrainly

7 0

1 year ago

Two workhorses tow a barge along a straight canal. Each horse exerts a constant force of magnitude F, and the tow ropes make an

morpeh [17]

Answer:

a) Fvt cosθ

b) Fv cosθ

Explanation:

Each horse exerts a force = F

the rope is inclined at an angle = θ

speed of each horse = v

a) In time t, the distance traveled d = speed x time

i.e d = v x t = vt

also, the resultant force = F cosθ

Work done W = force x distance

W = F cosθ x vt = Fvt cosθ

b) Power provided by the horse P = force x speed

P = F cosθ x v

P = Fv cosθ

8 0

1 year ago

1. A liquid of mass 250g is heated with an electric heater. Its temperature rises from 30°C to 80°C, the specific heat capacity

statuscvo [17]

Answer:

1) 50 seconds 2) 100°C

Explanation:

(Follows formula of Power=Energy/Time)

1) 500W x X = 2000J/kg°C x .25kg x 50°C

X = 50 seconds.

2) 2000W x 300s = 1000J/kg°C x 2kg x X

X = 300

Initial temperature => 400°C-300°C = 100°C

8 0

1 year ago

A 5.0-kg crate is resting on a horizontal plank. The coefficient of static friction is 0.50 and the coefficient of kinetic frict

Harlamova29_29 [7]

Answer:

The mass of the crate is 5kg.

We know that the force of friction can be obtained by:

F = N*k

where k is the coefficient of friction, where we use the static one if the object is at rest, and the kinetic one if the object os moving. N is the normal force

If we tilt the base making an angle of 30° with the horizontal, now the normal force against the plank will be equal to the fraction of the weight in the direction normal to the surface of the plank.

Knowing that the angle is 30°, then the fraction of the weight that pushes against the normal is Cos(30°)*W = cos(30°)*5kg*9.8m/s^2 = 42.4N

The fraction of the force in the parallel direction to the plank (the force that would accelerate the crate downwards) is:

F = sin(30°)*5k*9,8m/s = 24.5N

now, the statical friction force is:

Fs = 42.4N*0.5 = 21.2N

The statical force is less than the 24.5N, so the crate will move downwards, then the force that acts on the crate is the kinetic force of friction:

Fk = 42.4N*0.4 = 16.96N

Then, the total force that acts on the crate is:

total force = F - Fk = 24.5N - 16.69N = 7.54N and the direction of this force points downside along the parallel direction of the plank.

3 0

2 years ago