What is the wave speed of a wave that has a frequency of 50 Hz and a wavelength of 0.10 m? What is the frequency of a wave that has a wave speed of 20 m/s and a wavelength of 0.50 m?

Answer: D. 5cm

Explanation:

Given the following :

Focal length (f) = - 6.0 cm

Height of object = 15.0cm

Distance of object from mirror (u) = 12.0cm

Height of image produced by the mirror =?

Firstly, we calculate the distance of the image from the mirror.

Using the mirror formula

1/f = 1/u + 1/v

1/v = 1/f - 1/u

1/v = 1/-6 - 1/12

1/v = - 1/6 - 1/12

1/v = (- 2 - 1) / 12

1/v = - 3 / 12

v = 12 / - 3

v = - 4

Using the relation :

(Image height / object height) = (- image distance / object distance)

Image height / 15 = - (-4) / 12

Image height / 15 = 4 / 12

Image height = (15 × 4) / 12

Image height = 60 / 12

Image height = 5cm

Answer:

D. 5 cm

Explanation:got it right

Answer:

In general, the LONGER the string or air column of a musical instrument is, the more harmonics are generated.

Answer:

- Mass of the ball = 45 Kg

Explanation:

velocity attained by the ball:

  Distance/time= 54/9 = 6m/s (meter per sec)

As work done on ball = distance * force applied

                                   = 54*15

                                   =   810 J            -----------------  (i)

acc. to the conservation of energy:

work done  = kinetic energy + potential energy

                  =  1/2*m*[tex]v^{2}[/tex] + 0(as object is on ground)

                  = 1/2*m*[tex]6^{2}[/tex]

                   = 1/2*36*m

                   = 18*m                      ------------------- (ii)

∵,(i) =(ii)

18*m = 810

m=810/18

m= 45kg

Answer:

At which point does the planet have the least gravitational force acting on it?

Explanation:

In an elliptical orbit, when a planet is at its furthest point from the Sun, it is under the least amount of gravity, meaning that the force of gravity is strongest when it is closest.

Answer:

Point A

Explanation:

Recall that gravitational force is inversely proportional to the square of the distance between the 2 objects.

This means that the farther away the objects are from each other, the lesser their gravitational interaction will be.

In this case we can see that Point A is furthest away from the star, hence this will be the location with the least gravitational force from the star.

Answer:

See explanation

Explanation:

An element is a substance that cannot be chemically converted to another substance or broken down chemically into other substances.

Elements are represented by symbols. The symbol of an element may be the first one or two letters from its English or Latin name. For instance, the symbol of nitrogen is N. This symbol was derived from the first letter of its English name. The symbol for sodium is Na. This was derived from the first two letters of its Latin name, Natrium.

The periodic table is divided into horizontal rows called periods and vertical columns called groups. All members of the same period have the same number of electron shells while all members of the same group have the same number of valence electrons.

Metals are found towards the left hand side of the periodic table while non metals are found towards the right hand side of the periodic table. Metals looses electrons easily while nonmetals accepts electrons easily. Metals are good conductors of heat and electricity while non metals are poor conductors of heat and electricity.Metalloids have properties intermediate between those of metals and non metals and are found at the boarder line between metals and non metals in the periodic table. Metalloids include; silicon, boron, germanium, etc. The electrical conductivity of metalloids increases with temperature while the electrical conductivity of metals decreases with temperature.

Answer:

Explanation:

A voltmeter is usually connected in parallel with a part of a complete circuit.  The meter itself is connected in series to a very high resistance so that the amount of current drained is very tiny.

So you see, you could answer this in two ways, but since you are asking a question at a very beginning level, I think the answer should be

B

because voltmeters are made to measure potential difference and they are placed in parallel to the part measured. How it works is interesting but is not really part of the question.

Answer:

B. It is connected in parallel and measures potential difference.

Explanation:

A voltmeter is connected in parallel.

A voltmeter is used for measuring the electrical potential difference between two points in an electric circuit.

Answer:

The area of the rectangle plus the area of the triangle under the line

Explanation:

In this case, the object moves with constant acceleration. Initial speed of the object is 0.

Equation of kinematics :

v = u +at

v = at

v is directly proportional to time. If means that the graph is straight line passing through origin. We know that area under v-t graph gives displacement. So, the correct option is (c).

Answer:

c) the area of the rectangle plus the area of the triangle under the line

Explanation:

edge2021

Answer:

what will happen to the sound is the wavelength increases thus frequency decreases so the sound decreases as he move away from her car..