The ball of a ballpoint pen is 0.5 mm in diameter and has an ASTM grain size of 12. How many grainsare there in the ball

Given :

A badminton shuttlecock leaves the racquet traveling 30 m/s.

It goes over the net 0.5  seconds later with a speed of 10 m/s.

To Find :

The average acceleration of the shuttlecock.

Solution :

We know, average acceleration(a) is given by :

[tex]a = \dfrac{\text{Change in speed}}{\text{Time taken }}\\\\a = \dfrac{10-30}{0.5 }\ m/s^2\\\\a = -40\ m/s^2[/tex]

Therefore, the average acceleration is -40 m/s².

Answer:

The pressure at Mombasa is 101.396 KPascal.

Explanation:

Given: Reading on barometer = 760 mm

                                                  = 0.76 m

           Density of mercury = 1.36 x [tex]10^{4}[/tex] kg/[tex]m^{3}[/tex]

In this case, the pressure can be expressed as:

P = σhg

Where: σ is the density of mercury, h is height of mercury in the barometer, and g is the acceleration due of gravity.

But, g = 9.81 m/[tex]s^{2}[/tex]

So that,

P = 1.36 x [tex]10^{4}[/tex] x 0.76 x 9.81

  = 101396.16 Pascal

P = 101.395 KPascal

The pressure at Mombasa is 101.396 KPascal.

Answer:

v = 8[m/s]

Explanation:

In this case, the work that is exerted on the cart is the kinetic energy that allows the movement, so we can use the following equation of kinetic energy.

[tex]E_{kin}=Work\\E_{kin}=\frac{1}{2} *m*v^{2}[/tex]

Now replacing:

[tex]128=0.5*4*v^{2} \\v=\sqrt{64} \\v=8[m/s][/tex]

Answer:

v = 21.52 m/s

Explanation:

Given that,

The distance covered by the car, d = 6200 km

Time taken by the car, t = 80 hours

We need to find the speed of the car. The speed of an object is given by total distance dividing total time.

[tex]v=\dfrac{6200\times 10^3\ m}{80\times 3600}\\\\v=21.52\ m/s[/tex]

So, the speed of the car is 21.52 m/s.

Answer:

c

Explanation:

jsjdkksddssddddddmekekwkkwkekeke

Answer:

t = Δa / v

Explanation:

To know which option is not true, we shall fine a relationship between acceleration (a), velocity (v), time (t) and radius (r). This is illustrated below:

Acceleration can simply be defined as the rate of change of velocity with time. Mathematically, it is expressed as shown below:

Acceleration = change in velocity / time

a = Δv / t ..... (1)

But

Δv = v₂ – v₁

Substitute the value of Δv into equation (1)

a = Δv / t

a = v₂ – v₁ / t ....... (2)

From equation (1), make Δv the subject of the equation.

a = Δv / t

Cross multiply

Δv = at .... (3)

From equation (1), make t the subject of the equation.

a = Δv / t

Cross multiply

at = Δv

Divide both side by a

t = Δv /a ...... (4)

From circular motion, centripetal's force is given by:

F = mv²/r

F = ma꜀

Therefore,

ma꜀ = mv²/r

Cancel out m

a꜀ = v²/r

SUMMARY:

a = Δv / t

a = v₂ – v₁ / t

Δv = at

t = Δv /a

a꜀ = v²/r

Considering the options given in question above, t = Δa / v is not a true statement.

Answer:

Option 4

Explanation:

Answer:

196

Explanation:

subtract 24 from 220 to get your answer.

Answer:

100 beats for minute

Explanation:

Adults ( age 18 and over) 60 - 100 beats per minute

An object is moving with constant velocity downwards on a frictionless inclined plane that makes an angle of θ with the horizontal.

1. Which direction does the force of gravity act on the object?

2. Which direction does the normal force act on the object?

Which force is responsible for the object moving down the incline?

Answer:

The answer is below

Explanation:

1. When an object is moving with a constant velocity, the direction the force of gravity act on the object is DIRECTLY DOWN.

2. When an object is moving with a constant velocity, the direction the normal force act on the object "perpendicular to the surface of the plane."

3. When an object is moving with a constant velocity, the force that is responsible for the object moving down the incline is "the component of the gravitational force parallel to the surface of the inclined plane."

Answer:

no, not all three contains iron

no, not all three also contain magnets

Explanation:

a has the magnet

b and c have pieces of iron

Answer: A more detailed information like the nucleus of cells on the slide is seen as the magnification Increases.

Explanation:

The microscope is an instrument used in a laboratory to view magnified image of an object ( cells on a slide). There are two types:

--> Simple microscope and

--> Compound microscope.

Simple microscope is used to view an object using JUST ONE convex lens, and the image formed is usually erect and magnified.

Compound microscope has a higher magnification compared to a simple microscope. It is produced by using TWO CONVERGING LENS of short focal length. Here, the two lenses used are classified according to their positions. The lens near the object is called the objective lens while the one nearer to the eye is called the eyepiece lens.

The objective lens of the compound lens used in the laboratory has ×4, ×10, ×40, ×100 magnifications. As the magnification of the objective lens is increased from ×4 to ×10 a more detailed information of the image is seen as the diameter of field of view decreases. For example the constituents of a cell like the nucleus can be viewed using a higher magnification.

Answer:

D: 0.239

Explanation:

Equation for ideal efficiency is;

η = 1 - (T_c/T_h)

We are told that;

steam comes out at 112° C. Thus, T_h = 112°C. Converting to Kelvin gives; T_h = 112 + 273 = 385 K

The one exiting into the condenser is kept at 20°C. Thus; T_c = 20 + 273 = 293 K

Thus;

η = 1 - (293/385)

η = 0.239

Answer:

the answer is up the bird will go up

Explanation:

Answer:

After time 2t, the wheel will turn through an angle of 100 rad.

Explanation:

Given;

initial velocity of the wheel, [tex]\omega_i = 0[/tex]

time of motion, t = t

angular distance, θ = 25 rad

The constant angular acceleration is calculated as;

[tex]\theta = ut + \frac{1}{2}at^2\\\\\theta = 0 + \frac{1}{2}at^2\\\\2\theta = at^2\\\\a = \frac{2\theta }{t^2} \\\\a = \frac{2\ \times \ 25 }{t^2}\\\\a = \frac{50}{t^2} \\\\when \ t = 2t\\\\\theta = \frac{1}{2}at^2\\\\\theta = \frac{1}{2}(\frac{50}{t^2})(2t)^2\\\\\theta =\frac{1}{2}(\frac{50}{t^2})(4t^2)\\\\\theta = 100 \ rad[/tex]

Therefore, after time 2t, the wheel will turn through an angle of 100 rad.

The angle of the wheel would have turned after time 2t is equal to 100 rad.

Given the following data:

To determine the angle of the wheel would have turned after time 2t:

First of all, we would determine the angular acceleration of the wheel by using the second equation of rotational motion.

[tex]\theta = ut + \frac{1}{2} at^2\\\\25 =0(t) + \frac{1}{2} at^2\\\\25=\frac{1}{2} at^2\\\\50=at^2\\\\a=\frac{50}{t^2} \;rad/s^2[/tex]

Next, we would determine the angle the wheel would have turned after time 2t:

[tex]\theta = ut + \frac{1}{2} at^2\\\\\theta = 0(2t) + \frac{1}{2} (\frac{50}{t^2} )(2t)^2\\\\\theta = \frac{25}{t^2} \times 4t^2\\\\\theta = 25\times 4\\\\\theta = 100\;rads[/tex]

Read more: https://brainly.com/question/8898885

Answer:

[tex]U=5*10^7ft.Ib[/tex]

Explanation:

From the question we are told that

Weight  [tex]W= 10000bs[/tex]

Altitude [tex]H=5000ft[/tex]

Speed    [tex]V=125kts\\1kts=0.514m/s\\V=125*0.514=>64.25m/s[/tex]

Generally the equation for Potential energy ids mathematically given as

[tex]Potential\ Energy\ U=mgh[/tex]

[tex]U=Wh[/tex]

[tex]U=10000*5000[/tex]

[tex]U=5*10^7ft.Ib[/tex]

Answer:

25 cm

Explanation:

Given that :

Displacement, x = 50 cm

In a spring, the force is given thus ;

F = kx ; where, F = Force, k = spring constant

Hence,

F = 50k - - - (1)

If two identical springs are attached to the mass ;

Fnet = F1 + F2

Fnet = F = kx' + kx'

x' = Displacement

Spring constant k and x' will be the same in the two springs ;

Hence,

F = 2kx' - - - (2)

Equating (1) and (2)

F = F

50k = 2kx'

50 = 2x'

x' = 50 / 2

x' = 25

Hence, the spring will stretch by 25cm

Answer:

25m

Explanation:

The correct answers for the given paragraph are as follow:

1.

The digestive enzymes are the proteins that tends to break down the larger molecules like fats, proteins and carbs into smaller molecules.

Thus, the correct answer is Digestive Enzyme.

2.

The skeletal system is the framework of body, consisting of bones and various connective tissues. It provides the mechanical support and produces red blood cells.

Thus, the correct answer is skeletal system.

3. The organ system that protects the body's internal environment and stores the fat is known as Integumentary system.

Thus, the correct answer is integumentary system.

4.

The cardiovascular system enables the transport of nutrients, glasses and wastes to and from cells. Also, it is used for the transportation of nutrients and oxygen-rich blood to all parts of the body and to carry deoxygenated blood back to the lungs.

Thus, the correct answer is cardiovascular system.

5.

Endocrine glands are responsible for the secretion of hormones into the bloodstream to regulate the cellular activities.

Thus, the correct answer is Endocrine glands.

Learn more about the human organs and digestive system here:

https://brainly.com/question/16347243

Explanation:

I am not sure about this question sry but u can try asking a tutor u don't need to use any points

Answer:

sport is an activity that involves movement and teamwork.

hobby is a personal interest that you enjoy doing often.

Explanation:

:)

Answer:

In our everyday life, the deltoids take on most of the work in rotating our arms, but besides that the deltoid muscle also allows us to carry objects at a safe distance from the body. It is also responsible from stopping a dislocation or injury to the humerus when we carry something heavy.

Answer:

Lifting, pushing and pulling

Explanation:

it uses it

Answer:

The speed needed to escape from the solar system starting from the surface of Neptune is approximately 23557.615 meters per second.

Explanation:

The escape speed needed to escape from the gravitational influence of a planet ([tex]v_{e}[/tex]), measured in meters per second, is derived from Newton's Law of Gravitation and Principle of Energy Conservation and defined by the following formula:

[tex]v_{e} = \sqrt{\frac{2\cdot G\cdot M}{R} }[/tex] (1)

Where:

[tex]G[/tex] - Gravitational constant, measured in cubic meters per kilogram-square second.

[tex]M[/tex] - Mass of Neptune, measured in kilograms.

[tex]R[/tex] - Radius from the center to surface, measured in kilograms.

If we know that [tex]G = 6.672\times 10^{-11}\,\frac{m^{3}}{kg\cdot s^{2}}[/tex], [tex]M = 1.024\times 10^{26}\,kg[/tex] and [tex]R = 24.622\times 10^{6}\,m[/tex], then the escape speed needed is:

[tex]v_{e} =\sqrt{\frac{2\cdot \left(6.672\times 10^{-11}\,\frac{m^{3}}{kg\cdot s^{2}} \right)\cdot (1.024\times 10^{26}\,kg)}{24.622\times 10^{6}\,m} }[/tex]

[tex]v_{e} \approx 23557.615\,\frac{m}{s}[/tex]

The speed needed to escape from the solar system starting from the surface of Neptune is approximately 23557.615 meters per second.

Answer:

Explanation:

Eddy current are loops of electric currents which are induced within conductors when there is a change in magnetic field in the conductor through Faraday's Law of induction.

They are applied in electromagnetic braking. This is where the eddy current acts as brakes to stop moving objects. However, they are used along side mechanical braking systems.

Used in separation of metals such as Aluminum from other metals. Using the eddy current separator, ferrous elements are attracted to the magnet while aluminum being non-ferrous ,is left  separated.

Used in identifying metals in vending machines. These machines use eddy currents to detect fake coins where the fake coins will slow at a certain speed to be identified.

Testing of structure of aircrafts apply eddy currents through procedures of Non destructive examination.

They are used in defect detecting and safety hazards application. Defects in heat exchanger tubes can be detected by eddy currents.

Answer:

(v-u) = 1.27 m/s

Explanation:

Given that,

Mass of a car, m = 1100 kg

Force with which the wall strikes, F = 4000 N

Time, t = 0.35 s

We need to find the change in velocity of the car.

The net force acting on the car is given by :

F = ma

a is acceleration

[tex]F=\dfrac{m(v-u)}{t}\\\\(v-u)=\dfrac{Ft}{m}\\\\(v-u)=\dfrac{4000\times 0.35}{1100}\\\\(v-u)=1.27\ m/s[/tex]

(v-u) is the change in velocity. Hence, the change in the velocity of the car is 1.27 /s.

Answer:

The force required is 3,104 N

Explanation:

Force

According to the second Newton's law, the net force exerted by an external agent on an object of mass m is:

F = ma

Where a is the acceleration of the object.

On the other hand, the equations of the Kinematics describe the motion of the object by the equation:

[tex]v_f=v_o+at[/tex]

Where:

vf is the final speed

vo is the initial speed

a is the acceleration

t is the time

Solving for a:

[tex]\displaystyle a=\frac{v_f-v_o}{t}[/tex]

We are given the initial speed as vo=20.4 m/s, the final speed as vf=0 (at rest), and the time taken to stop the car as t=7.4 s. The acceleration is:

[tex]\displaystyle a=\frac{0-20.4}{7.4}[/tex]

[tex]a=-2.757\ m/s^2[/tex]

The acceleration is negative because the car is braking (losing speed). Now compute the force exerted on the car of mass m=1,126 kg:

[tex]F = 1,126\ kg * 2.757\ m/s^2[/tex]

F= 3,104 N

The force required is 3,104 N

Answer:

First, if you are inside a spaceship that travels with a relativistic speed, your inner time does not change. So your cells and DNA feel the time exactly as how they would feel it on Earth. This means that if you spend 12 years travelling on your spaceship, you will age those 12 years, while the ones that are still in Earth may be experienced time in a different way (The ones on Earth may measure the time between your departure and your arrival as 15 years, for example, so they feel the time in a different way).

Then we only need to solve the equation:

Distance/time = speed

Distance = 300 Light years.

Time = 12 years:

300 light-years/12 years  = speed = 25*C

where C is the speed of light:

C = 3*10^8 m/s

From this, we can conclude that you would need to travel a lot faster than the speed of light.

Then the speed is:

speed = 25*3*10^8 m/s= 7.5*10^9 m/s.

Explanation:

Elastic string constant (k)

= Slope of the graph F/x

= 15.0N/10.0m = 1.50N/m

Hence,

EPE = 0.5kx² = 0.5(1.50N/m)(3.0m)² = 6.75J.

Answer:

6.8

Explanation: