7. Calculate the force applied on an object if the Pressure exerted is 90 Pascal over an area of 900 cm2.

Answer:

Concave mirror makes someone looking at it look dwarf or short, while convex mirror stretches the person making the person look weird.

Answer:

1. Urea,                    (d)Fertilizer

2. Combines,          (c) Harvesting and threshing

3. Silos,                   (b) Storage of grains

4. Seed drills,          (a) Sowing seeds

5. Irrigation,             (f) Sprinklers

6. Tilling,                  (e) Preparation of soil

Explanation:

1) Urea is a widely used and important fertilizer in the agricultural industry

2) The combine harvester combines three categories of harvesting grain drops such as threshing reaping and winnowing

3) Silos are used to store grains

4) A seed drill is a seed planting mechanism for burying seeds to a particular depth during seed planting

5) Irrigation is the application of required volume of water to plants

6) Tilling is the digging, turning, and staring operations meant to prepare the soil.

Answer:

the photo is a bit blur

Answer:

Explanation:

Initial velocity (u) of the Bullet = 400 m/sec

Final velocity (v) of the Bullet = 100 m/sec

Bullet passed through the block in (t) = 0.0004 sec  

Using 1st Equation of motion :

400 m/s = 100 m/s - a (0.0004)

Deceleration of Bullet = 750,000 m/sec^2

(a) F (force exerted by the wooden block on the bullet) = F (force exerted by the bullet on the wooden block)

F = m * a = 0.008 * 750,000 = 6000 N

(b) Using 3rd Equation of motion :

[tex]v^{2} = u^{2} - 2aS[/tex]

10000 = 160000 - 2 * 750,000 * S

Thickness of wood (S) = 0.1 m

Answer:

b. There will be more electrons emitted.

Explanation:

In photoelectric emission, the energy of the emitted electron is dependent on the frequency of the wave incident on the plate; but not the intensity. The rate of electron emission per unit time however depends on the intensity of the incident light. So increasing the intensity of the light at constant frequency will only affect the number of electrons emitted per unit time.

Answer:

a business who buys goods and services

Answer

As the angle of incidence increases in Figure 2.8, a point is finally reached where the refracted ray does not emerge at the second layer but lie along the interface. This particular angle of incidence at which the angle of refraction is 90° and the refracted ray lies along the interface is known as the critical angle. At and beyond the critical angle, there is no transmitted ray and therefore a very high reflected ray will be recorded .

Therefore,

sinθisin90=Vp1Vp2

But, sin 90 = 1.

At critical angle,

sinθcritical=Vp1Vp2

A critical refracted wave travels along the interface between layers and is refracted back into the upper layer at the critical angle. The waves refracted back into the upper layer are called head waves or first-break refractions because at certain distances from a source, they are the first arriving energy. Recorded first-break refraction is shown in Figure 2.10.

Note that these first-break refractions can give us important information about the shallow velocities on land seismic data.

Note also that seismic data are acquired in such a way that reflections from horizons of interest are in the pre-critical region, even at the farthest offset in the data.

In reality, part of the seismic energy arriving at an interface is transmitted and refracted, and another part of the energy is reflected at that same interface. Given that there are many reflectors in the subsurface, there will be many paths from source to receiver, each of them with a different travel time. The proportion of energy reflected depends on the material properties of the two bounding layers and on the angle of incidence

The answer is 65.3 inches tall

Explanation:

To know the heigh of Sammy in inches it is necessary to convert the 5 feet to inches and add this number to 5.3 inches as the statement mentions "Sammy is 5 feet and 5.3 inches tall". Additionally, it is known each foot is equal to 12 inches ( 1 foot = 12 inches). According to this, the simplest method to convert feet to inches is to multiply the feet given by 12. The process is shown below:

1 foot  = 12 inches

feet to inches =  number of feet x 12

5 feet x 12 = 60 inches

This means 5 feet is equal to 60 inches. Now, 60 inches + 5.3 inches = 65.3 inches (total height of Sammy in inches)

Answer:

22.2 m/s or 80 km/h

Explanation:

Given that

Distance travelled by the car, d = 240 km

Time taken by the car, t = 3 hours.

Speed of the car, v = ? m/s

for easy calculations, we will be converting the units to meters and seconds respectively.

240 km to meters would be

240 * 1000 m = 240000 m

3 hrs to seconds would be

3 * 60 mins * 60 seconds = 10800 s

now, we have our distance and time to be

d = 240000 m

t = 10800 s

speed is defined as the ratio of distance with respect to time taken, effectively,

Speed = distance/time

speed, v= 240000 / 10800

v = 22.2 m/s

therefore, the speed of the car during the time is 22.2 m/s, or if the speed is needed in km/h, we can convert it

22.2 * 3600/1000 =

80 km/h

Answer:

The correct option is;

[tex]_{1}^{2}\textrm{He} + _{1}^{1}\textrm{H} \rightarrow _{3}^{2}\textrm{He} + energy[/tex]

Explanation:

The second step of the fusion process is the reaction (combination) where a Deuterium combines with a hydrogen to produce one helium 3, 3He, nucleus and a energy photon as follows;

[tex]_{1}^{2}\textrm{He} + _{1}^{1}\textrm{H} \rightarrow _{3}^{2}\textrm{He} +\gamma \ (energy)[/tex]

After which the produced Helium-3 combines to form the Helium nucleus an emit 2 protons

Steps 1 and 2 are take place two times (producing 26 MeV energy) before the step three (the combination of the formed helium-3) takes occurs.

Answer:

C on edge

Explanation:

Just did it and got it right :)

Answer:

Transverse wave

Explanation:

Its because in transverse wave the particle displacement is perpendicular to the direction of wave propagation..hope it helps you...

Answer: √(L/g)

Explanation:

Here we only work with the units:

The unit of the period is units of time, so we have:

[T] = [s]

Now, the units of the length of the pendulum are units of distance:

[L] = [m]

And the units of the acceleration are:

[g] = [m/s^2]

Now, we want to work with those two in such way that the end result is only in seconds.

First, we can see that in g we have seconds square, so we know that we should use a square root.

Then we can divide L by g in order to remove the distance unit, and to have the time unit in the numerator

[L/g] = [m*s^2/m] = [s^2]

Now we apply the square root:

[√(L/g)] = [√s^2] = [s]

Then the combination is: √(L/g)

T = k*√(L/g)

where k is the constant of proportionality.

Answer:

1.) Sowing

2.) Respiration

3.) Soil preparation or cultivation or ploughing

4.) Fertility

5.) 2, 4 -D

6.) winnowing threshers

7.) Surface irrigation and sprinkler irrigation

8.) Weeds

9.) Transplantation

10.) Aeration

Explanation:

1.) Seed drill sows crop seed

2.) Ploughing assist in the respiration and penetration of the roots of a growing plants

3.) Tilling the soil is breaking of the soil lumps and turning of the soil

4.) Manure and fertilizers supply nutrient to the soil for the uptake by plant in food production

5.) 2, 4 -D are a range of weedicide containing 2,4-D as the active ingredient

6.) Winnowing is the separation of grain from straw

Threshers remove seeds from husks and stalks

7.) Surface irrigation -gravity enables the flow of the water

and sprinkler irrigation- Use of preset tools for irrigation

8.) Weeds are the unwanted, in situ, growing plants close to the crops

9.) Transplantation is the method of relocating plants

10.) Excess water limits access of the roots and seeds to atmospheric oxygen

Answer:

10N

Explanation:

Applying the Hooke law:

F = kx

F: Force

k: stiffness coefficient

x: stretched distance

F = 10N/m x 1m = 10N

Answer:

3.33 N

Explanation:

First, find the acceleration.

Given:

Δx = 3 m

v₀ = 0 m/s

t = 3 s

Find: a

Δx = v₀ t + ½ at²

3 m = (0 m/s) (3 s) + ½ a (3 s)²

a = ⅔ m/s²

Use Newton's second law to find the force.

F = ma

F = (5 kg) (⅔ m/s²)

F ≈ 3.33 N

Answer:

585×10⁸ m

Explanation:

Distance = rate × time

d = (2.998×10⁸ m/s) (3.25 min) (60 s/min)

d = 585×10⁸ m

Answer:

In order to be in translational equilibrium, the net force (sum of the forces) must be 0.

Answer:

K.E of truck > K.E of car

Explanation:

Mass of the truck = 8000Kg

K.E=[tex]\frac{1}{2} mv[/tex]

K.E =[tex]\frac{1}{2}*8000*v\\ 4000v[/tex]

Mass of the car = 1000 Kg

K.E of the car =[tex]\frac{1}{2}*1000*v\\ 500v[/tex]

Therefore Kinetic energy of the truck is greater than that of the car

Answer:

0.4 N

Explanation:

The weight mg is 8 N, so the mass is:

mg = 8 N

m = 8 N / g

m = 8 N / (10 m/s²)

m = 0.8 kg

The force needed to accelerate it to 0.5 m/s².

F = ma

F = (0.8 kg) (0.5 m/s²)

F = 0.4 N

Answer:

find the sum of the inital and final velocitys and divide by 2 to find the average

Answer:

the final statements the correct one is. The second

The iron piece exerts a force of 1 N on the magnet in the opposite direction

Explanation:

In this exercise they give us the force exerted by a magnet on an iron bar and ask us the force that the iron bar exerts on the magnet. We can see that these are action and reaction forces, which by Newton's third law must be of equal magnitude and opposite direction, each applied to one of the bodies.

the final statements the correct one is. The second

The iron piece exerts a force of 1 N on the magnet in the opposite direction

Answer:

0.66*10^-6m

Explanation:

We know that the bright fringes are placed on the screen as follows

Ym= m*(lambda xL/d)

But we are given

L= 5.05

Deta Y= 1.59

d = 0.21

1.59* 10^-2m= lambda * 5.05m/2.1*10^-4m

So lambda=

1.59* 10^-2m x 2.1*10^-4m/ 5.05m

= 0.66*10^-6m

Answer:

(II). The fractions in simplest form

[tex]\dfrac{31}{35}[/tex], [tex]\dfrac{91}{165}[/tex] and [tex]\dfrac{13}{5}[/tex]

(III). The fractions in ascending order

[tex]\dfrac{91}{165}<\dfrac{31}{35}<\dfrac{13}{5}[/tex]

Explanation:

Given that,

(I). Represent the fractions in pictorial form

(II). Write the fractions in simplest form.

(III). Arrange them in ascending order.

Suppose, The fractions in pictorial form

(a). [tex]\dfrac{3}{5}+\dfrac{2}{7}[/tex]

(b). [tex]\dfrac{9}{11}-\dfrac{4}{15}[/tex]

(c). [tex]\dfrac{7}{10}+\dfrac{2}{5}+\dfrac{3}{2}[/tex]

We need to write in simplest form

Using given fraction

(a). [tex]\dfrac{3}{5}+\dfrac{2}{7}=\dfrac{3\times7}{5\times7}+\dfrac{2\times5}{7\times5}[/tex]

[tex]\dfrac{3}{5}+\dfrac{2}{7}=\dfrac{21}{35}+\dfrac{10}{35}[/tex]

[tex]\dfrac{3}{5}+\dfrac{2}{7}=\dfrac{21+10}{35}[/tex]

[tex]\dfrac{3}{5}+\dfrac{2}{7}=\dfrac{31}{35}[/tex]

(b). [tex]\dfrac{9}{11}-\dfrac{4}{15}=\dfrac{9\times15}{11\times15}-\dfrac{4\times11}{15\times11}[/tex]

[tex]\dfrac{9}{11}-\dfrac{4}{15}=\dfrac{135-44}{165}[/tex]

[tex]\dfrac{9}{11}-\dfrac{4}{15}=\dfrac{91}{165}[/tex]

(c). [tex]\dfrac{7}{10}+\dfrac{2}{5}+\dfrac{3}{2}=\dfrac{7}{10}+\dfrac{2\times2}{5\times2}+\dfrac{3\times5}{5\times2}[/tex]

[tex]\dfrac{7}{10}+\dfrac{2}{5}+\dfrac{3}{2}=\dfrac{7}{10}+\dfrac{4+15}{10}[/tex]

[tex]\dfrac{7}{10}+\dfrac{2}{5}+\dfrac{3}{2}=\dfrac{7+4+15}{10}[/tex]

[tex]\dfrac{7}{10}+\dfrac{2}{5}+\dfrac{3}{2}=\dfrac{26}{10}[/tex]

[tex]\dfrac{7}{10}+\dfrac{2}{5}+\dfrac{3}{2}=\dfrac{13}{5}[/tex]

We need to arrange them in ascending order

Using simplest form

The simplest fraction in ascending order

[tex]\dfrac{91}{165}<\dfrac{31}{35}<\dfrac{13}{5}[/tex]

Hence, This is required solution.

Answer:

Wholesale Market. 1. The market for the sale of goods to a retailer. That is, a wholesaler receives large quantities of goods from a manufacturer and distributes them to stores, where they are sold to consumers. ... The market for the sale of securities to institutional investors rather than individuals.

Answer:

mechanical energy or chemical energy

Answer:

Iron expands because heating increases the space between the molecules

Explanation:

According to the kinetic molecular theory, all matter is composed of atoms and molecules which are in constant motion.

When a substance is heated, molecules of the substance begin to vibrate faster. This faster vibration leads to increased space between the molecules (expansion) . The kind of motion motion and degree of spacing of the molecules determine the state of matter in which the substance is found.

Hence, when an iron bar is heated, it expands due to increased motion of its molecules leading to spaces between them.

Answer:

27.336

Explanation:

The atomic mass is the weighted average of the atomic masses of the isotopes.  Simply multiply each isotopes's atomic mass by its relative abundance, then sum the results.

m = 0.8233 × 26.975 + 0.1767 × 29.018

m = 27.336

Answer:

a) La magnitud del desplazamiento es de 5 m

La magnitud de la fuerza es 20 N

b) El trabajo realizado por la fuerza es de 100 J

c) El ángulo entre la fuerza y el plano es 0 °

Explanation:

a) La magnitud del desplazamiento se encuentra por la relación;

[tex]\left | X \right | = \sqrt{X_{x}^{2}+X_{y}^{2}}[/tex]

Lo que da;

[tex]\left | X \right | = \sqrt{4^{2}+3^{2}} = 5 \ m[/tex]

De manera similar, la magnitud de la fuerza, F, se encuentra como sigue;

[tex]\left | F \right | = \sqrt{F_{x}^{2}+F_{y}^{2}}[/tex]

Lo que da;

[tex]\left | F \right | = \sqrt{16^{2}+12^{2}} = 20 \ N[/tex]

b) El trabajo, W, realizado por la fuerza = Fuerza, F × Distancia, X

∴ Ancho = 20 N × 5 m = 100 N · m = 100 J

c) La dirección de la fuerza viene dada por la siguiente fórmula;

[tex]tan^{-1} \left (\dfrac{F_y}{F_x} \right ) = tan^{-1} \left (\dfrac{12}{16} \right ) = 38.9^{\circ}[/tex]

La dirección del plano viene dada por la siguiente fórmula;

[tex]tan^{-1} \left (\dfrac{X_y}{X_x} \right ) = tan^{-1} \left (\dfrac{3}{4} \right ) = 38.9^{\circ}[/tex]

Por tanto, el ángulo entre la fuerza y el plano = 0 °

La fuerza actúa a lo largo del plano.

Explanation:

It is given that,

The Displacement x of particle moving in one dimension under the action of constant force is related to the time by equation as:

[tex]x=4t^3+3t^2-5t+2[/tex]

Where,

x is in meters and t is in sec

We know that,

Velocity,

[tex]v=\dfrac{dx}{dt}\\\\v=\dfrac{d(4t^3+3t^2-5t+2)}{dt}\\\\v=12t^2+6t-5[/tex]

(a) i. t = 2 s

[tex]v=12(2)^2+6(2)-5=55\ m/s[/tex]

At t = 4 s

[tex]v=12(4)^2+6(4)-5=211\ m/s[/tex]

(b) Acceleration,

[tex]a=\dfrac{dv}{dt}\\\\a=\dfrac{d(12t^2+6t-5)}{dt}\\\\a=24t+6[/tex]

Pu t = 3 s in above equation

So,

[tex]a=24(3)+6\\\\a=78\ m/s^2[/tex]

Hence, (a) (i) v = 55 m/s (ii) v = 211 m/s and (b) 78 m/s²

Answer:

kinetic energy is 1/2mv^2.

which is 1/2×0.05×3^2

1/2×0.05×9.

1/2×0.45=

0.45÷2=0.225~0.23J