When a wave is allowed to pass through a medium, the wave has been
a)transmitted
b)reflected
c)absorbed
d)encoded

Answer:

The time taken for the train to cross the bridge is 9.01 s

Explanation:

Given;

length of the train, L₁ = 90 m

length of the bridge, L₂ = 0.06 m

speed of the train, v = 10 m/s

Total distance to be traveled, = L₁ + L₂

                                                  = 90 m + 0.06 m

                                                   = 90.06 m

Time of motion = Distance / speed

Time of motion = 90.06 / 10

Time of motion = 9.006 s ≅ 9.01 s

Therefore, the time taken for the train to cross the bridge is 9.01 s

Answer:

P=I²R

Explanation:

P=2*10^-3 square times 10

4 times ten raise to power minus 5

Answer:

Force = 11.33 Newton

Explanation:

Given the following data;

Impulse = 34 Ns

Time = 3 seconds

To find the force acting on the object;

Impulse = force * time

Substituting into the formula, we have;

34 = force * 3

Force = 34/3

Force = 11.33 Newton

Note: the impulse of an object is equal to the change in momentum experienced by the object.

Answer:

the answer is c

Explanation:

i did the test

In the context of physics, work is defined to be the movement of an object when you apply a (pushing or pulling) force.

If you lifted a box to move it upward, then you are doing work. If you slide that box along the floor, then you are also doing work. However, if you try to lift something very heavy, but cannot move it at all, then 0 work is being applied. This is because the object hasn't moved. You need displacement to have work happen.

So that's why a physicist would not consider studying doing "work" (in the context of physics), though I'm sure they would be able to agree that studying does exercise the mind.

Assuming brown hair (B) color is completely dominant over blond hair (b), then the father's genotype must be bb.

Answer:

f = 14.28 m

Explanation:

Given that,

Object distance, u = -50 m

The image distance from the lens, v = +20 m

We need to find the focal length of the lens. Let the focal length is f. Using the lens formula,

[tex]\dfrac{1}{v}-\dfrac{1}{u}=\dfrac{1}{f}[/tex]

Put all the values,

[tex]\dfrac{1}{20}-\dfrac{1}{(-50)}=\dfrac{1}{f}\\\\f=14.28\ m[/tex]

So, the focal length of the lens is equal to 14.28 m.

Answer: Seema

Explanation:

When an object is on the floor, there is a force of friction acting on it. This force is higher if the object is heavier because the object would be pushing against the floor with more force.

To push such an object, one would have to apply enough force to break the friction holding the object to the floor and so with heavier objects, more force is needed to push the object because there is more friction acting on it.

Answer: C is correct :)

Explanation:

Answer:

Resistance in pencil sharpener = 12 ohms

Explanation:

Given:

Voltage in pencil sharpener = 6 volts

Current in pencil sharpener = 0.5 amps

Find:

Resistance in pencil sharpener

Computation:

Resistance = Voltage / Current

Resistance in pencil sharpener = Voltage in pencil sharpener / Current in pencil sharpener

Resistance in pencil sharpener = 6 / 0.5

Resistance in pencil sharpener = 12 ohms

Answer:

Frequency of sound wave = 198.83 hertz (Approx.)

Explanation:

Given:

Velocity of sound wave in air = 340 m/s

Wavelength = 1.71 meter

Find:

Frequency of sound wave

Computation:

Frequency = Velocity / Wavelength

Frequency of sound wave = Velocity of sound wave in air / Wavelength

Frequency of sound wave = 340 / 1.71

Frequency of sound wave = 198.8304

Frequency of sound wave = 198.83 hertz (Approx.)

Answer: C: Fluorine

Explanation:

Carbon is in period two on the periodic table of elements. The only other elements in this period are lithium, borilliym, boron, nitrogen, oxygen, flourine, and neon. Therefore, the answer must be C.

Answer:

a. t = 2 s

b. vf = 20 m/s

Explanation:

a.

We can the second equation of motion to find out the time to reach the ground:

[tex]h = v_it + \frac{1}{2}at^2[/tex]

where,

h = height = 20 m

vi = initial velocity = 0 m/s

t = time taken to reach the ground = ?

a = acceleration = 10 m/s²

Therefore,

[tex]20\ m = (0\ m/s)t+\frac{1}{2} (10\ m/s^2)t^2\\\\t^2 = \frac{20\ m}{5\ m/s^2}\\\\t = \sqrt{4\ s^2}[/tex]

t = 2 s

b.

Here, we will use the first equation of motion to find the final speed:

[tex]v_f = v_i + at\\v_f = 0\ m/s + (10\ m/s^2)(2\ s)[/tex]

vf = 20 m/s

Answer:

The intensity of the net electric field will:

[tex]E_{net}=E_{1}+E_{2}=2.52*10^{7}\: N/C[/tex]

Explanation:

Here we need first find the electric field due to the first charge at the midway point.

The electric field equation is given by:

[tex]|E_{1}|=k\frac{q_{1}}{d^{2}}[/tex]

Where:

So, we will have:

[tex]|E_{1}|=(9*10^{9})\frac{20*10^{-6}}{0.1^{2}}[/tex]

[tex]|E_{1}|=1.8*10^{7}\: N/C[/tex]

The direction of E1 is to the right of the midpoint.

Now, the second electric field is:

[tex]|E_{2}|=k\frac{q_{2}}{d^{2}}[/tex]

[tex]|E_{2}|=(9*10^{9})\frac{8*10^{-6}}{0.1^{2}}[/tex]

[tex]|E_{2}|=7.2*10^{6}\: N/C[/tex]

The direction of E2 is to the right of the midpoint because the second charge is negative.

Finally, the intensity of the net electric field will:

[tex]E_{net}=E_{1}+E_{2}=2.52*10^{7}\: N/C[/tex]

I hope it helps you!

The net electric field midway between these two charges is 2.52 x 10⁷ N/C.

The electric field strength between two point charges is the force per unit charge.

Electric field strength due to +20.0 μC charge

[tex]E _1 = \frac{kq_1}{r^2} \\\\E_ 1 = \frac{9 \times 10^9 \times 20 \times 10^{-6}}{(0.1)^2} \\\\E _1 = 18 \times 10^6 \ N/C[/tex]

Electric field strength due to -8μC charge

[tex]E _2 = \frac{kq_2}{r^2} \\\\E_ 2 = \frac{9 \times 10^9 \times 8 \times 10^{-6}}{(0.1)^2} \\\\E _2 = 7.2 \times 10^6 \ N/C[/tex]

The net electric field midway between these two charges is calculated as follows;

[tex]E_{net} = 18 \times 10^6 \ + \ 7.2 \times 10^6\\\\E_{net} = 25.2 \times 10^6 \ N/C\\\\E_{net} = 2.52 \times 10^7 \ N/C[/tex]

Learn more about electric field here: https://brainly.com/question/14372859

Answer:

Provides an estimate of how many planets there are in our galaxy that may harbor technically communicative life-forms.

Explanation:

A planet can be defined as a large celestial body having sufficient mass to allow for self-gravity and make it assume a nearly circular shape (hydrostatic equilibrium), revolves in an orbit around the Sun in the solar system and has a cleared neighborhood.

Basically, the planets are divided into two (2) main categories and these includes;

I. Outer planets: these planets are beyond the asteroid belt and comprises of jupiter, saturn, uranus and neptune, from left to right of the solar system.

II. Inner planets: these planets are the closest to the sun and comprises of mercury, venus, earth and mars.

These outer planets are made mostly of gases (hydrogen and helium) causing them to be less dense than the solid inner planets. These gases are generally known to be less dense in terms of physical properties.

Some examples of the planet are Mars, Venus, Earth, Mercury, Neptune, Jupiter, Saturn, Uranus, etc.

The Drake equation provides an estimate of how many planets there are in our galaxy that may harbor technically communicative life-forms. It is a probabilistic mathematical expression.

Answer:

The correct answer would be:

B.

the number of communicating civilizations in the cosmos

#PLATOFAM

Have a nice day!

Answer: 0.5A

Explanation:

According to Ohm's law, the Voltage(V) when a current flows through a resistor can be calculated by using the formula:

V = IR

where,

V = Voltage = 200V

I = current in amps (A)

R = resistance in ohms (Ω) = 400Ω

Current = Voltage / Resistance

I = V/R

I = 200/400

I = 0.5A

Therefore, the current is 0.5 Ampere

Answer:

The acceleration of the nfl players is 4.167 m/s²

Explanation:

Given;

velocity of the  nfl players, v = 10 m/s

time of motion of the nfl players = 2.4 s

Acceleration is the change in velocity with time.

The acceleration of the nfl players is calculated as follows;

a = v/t

where;

a is the acceleration of the nfl players

a = 10 / 2.4

a = 4.167 m/s²

Therefore, the acceleration of the nfl players is 4.167 m/s²

What are the following statements?

Answer:

immma send you the link friend me on hereExplanation:

Answer:

» Battery or cell

» Switch

» Connecting wires

» Resistor or appliance

Answer:

proof in explanation

Explanation:

First, we will calculate the number of half-lives:

[tex]n = \frac{t}{t_{1/2}}[/tex]

where,

n = no. of half-lives = ?

t = total time passed = 2100 million years

[tex]t_{1/2}[/tex] = half-life = 700 million years

Therefore,

[tex]n = \frac{2100\ million\ years}{700\ million\ years}\\\\n = 3[/tex]

Now, we will calculate the number of uranium nuclei left ([tex]n_u[/tex]):

[tex]n_u = \frac{1}{2^{n} }(total\ nuclei)\\\\n_u = \frac{1}{2^{3} }(6400\ million)\\\\n_u = \frac{1}{8}(6400\ million)\\\\n_u = 800\ million[/tex]

and the rest of the uranium nuclei will become thorium nuclei ([tex]u_{th}[/tex])

[tex]n_{th} = total\ nuclei - n_u\\n_{th} = 6400\ million-800\ million\\n_{th} = 5600\ million[/tex]

dividing both:

[tex]\frac{n_{th}}{n_u}=\frac{5600\ million}{800\ million} \\\\n_{th} = 7n_u[/tex]

Hence, it is proven that after 2100 million years there are seven times more thorium nuclei than uranium nuclei in the rock.

Answer:

The minimum pressure required to get water up to a restaurant on the top floor is 5.0176 x 10⁶ N/m²

Explanation:

Given;

height of the building, h = 512 m

density of water, ρ = 1000 kg/m³

The minimum pressure required to get water up to a restaurant on the top floor is calculated as follows;

P = ρgh

where;

P is the required minimum pressure

g is acceleration due to gravity = 9.8 m/s²

P = 1000 x 9.8 x 512

P = 5.0176 x 10⁶ N/m²

Therefore, the minimum pressure required to get water up to a restaurant on the top floor is 5.0176 x 10⁶ N/m²

Answer:

3.0 A Is the correct option

Explanation:

I = V / R

I = 12/ 4

= 3

Answer:

Milk Lactometer

Milk Lactometer: A lactometer is an instrument that is used to check for the purity of milk by measuring its density.

lactometer is used to determine the purity of milk

hope it is helpful to you

Answer:

1500kg

Explanation:

Initial velocity(u)=0m/s

Final velocity(v)=20m/s

Time taken=5s

Acceleration=v-u/t

Acceleration=20-0/5=4m/s^2

Force=6000N

Mass=?

Mass=Force/acceleration

= 6000/4

=1500kg

Answer:

The applied force on the vehicle is 5,000 N

Explanation:

From the question, we have the following parameters of the motion of the vehicle;

The form of the velocity with which the vehicle is travelling = Uniform velocity

The direction of motion of the vehicle = Along a straight and level stretch of the highway

The combined force which acts as resistance to the vehicle's motion = 5,000 N from rolling friction and resistance of the air opposite to the direction of motion

A vehicle travelling with uniform velocity has zero acceleration, therefore;

The acceleration of the vehicle, a = 0 m/s²

According to Newton's Second Law of Motion, we have;

Force, F = Mass, m × Acceleration, a

∴ The net force of acting on the vehicle, F = m × a

Where;

m = The mass of the vehicle

a = The acceleration of the vehicle = 0 m/s²

∴ F = m × 0 = 0

The net force on the vehicle = 0, therefore;

The applied force + The force of rolling friction and air resistance = 0

We therefore have;

The applied force + 5,000 N = 0

∴ The applied force = 0 - 5,000 N = -5,000 N

The applied force, F = 5,000 N in the direction of motion.

hope it is helpful to you

Answer:177.87

Explanation: