. Mass of a man is 40 kg. find his weight (g=9.8 m/s?)​

Answer:

Answer B is the correct answer: "Motion of one projectile as seen from the other is a straight line."

Explanation:

Let's write the equations of motion for each projectile, using that projectile [tex]a[/tex] is launched with velocity [tex]a[/tex] which has components associated with the angle of launching, given in x and y coordinates as: [tex]a_x\,\,and\,\,a_y[/tex].

Similarly, assume that projectile b is launched with velocity [tex]b[/tex] with components due to the launching angle = [tex]b_x\,\,and \,\,b_y[/tex]

then the equations of motion for the two projectiles launched at the same time (t) from the same spot (position that we assume to be at the origin of coordinates to simplify formulas) are:

[tex]x_a=a_x\,t\\y_a= a_y\,t-\frac{1}{2} g\,t^2\\and\\x_b=b_x\,t\\y_b= b_y\,t-\frac{1}{2} g\,t^2[/tex]

therefore, from the frame of reference of projectile "b", the x and y position of projectile "[tex]a[/tex]" would be:

[tex]x_{a\,b}= x_a-x_b= a_x\,t-b_x\,t=(a_x-b_x)\,t[/tex]  which is linear in "t"

[tex]y_{a\,\,b}=y_a-y_b= a_y\,t-\frac{1}{2} g\,t^2-\left[ b_y\,t-\frac{1}{2} g\,t^2\right]=(a_y-b_y)\,t[/tex] which is also linear in t.

Therefore the motion of one projectile with reference to the other is a straight line (answer B)

Notice as well that this two projectiles cannot collide because they have been launched together, and supposedly at different speeds and angles. The only way that they can share the same x-coordinate and the same y-coordinate at the same time "t" is if their velocity components are equal, which is not what we are told.

[tex]x_a=x_b\\a_x\,t= b_x\,t\\and\\y_a= y_b\\a_y\,t-\frac{1}{2} g\,t^2= b_y\,t-\frac{1}{2} g\,t^2\\a_y\,t=b_y\,t\\a_y=b_y[/tex]

Answer:

Electromagnetic waves or EM waves are waves that are created as a result of vibrations between an electric field and a magnetic field. In other words, EM waves are composed of oscillating magnetic and electric fields.

Explanation:

Answer:

Distance : 0.06533 meters or 65.33 mm

Explanation:

To solve this problem we can make the forces equal when the system is at equilibrium.

mass [tex]*[/tex] gravity ( constant ) = spring constant

where l = the length at which the rubber band is stretched

0.2 kg [tex]*[/tex] 9.8 m / s² = 30 N/m

1.96 kg [tex]*[/tex] m / s² = 30 N/m

l = 1.96 kg [tex]*[/tex] m / s² / 30 N/m = 0.06533 meters / 65.33 mm

The rubber band is stretched a distance of 0.06533 meters, or 65.33 mm.

Answer:

0.065

Explanation:

Apex i just got it right

Answer:

Solution

Given:

initial velocity (u)=0m/s (because an object

starts from the rest)

time (t)=3sec

diatance travelled(s)=14m(16-2=14)

acceleration (a)=?

Now,

According to the formula

s=ut+1/2at^2

or,14 =0×3+1/2×a×3^2

or, 14=0+a/2×9

or, 14=9a/2

or, 9a=28

or, a=28/9

or, a=3.1 m/s^2

Therefore, the acceleration of the object is 3.1m/s^2 ans.

Answer:

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

Answer:

Electronic tools provide more accurate data and this data is more efficient fast and easy to understand

Hope this helps you!!

Answer:

0.75 A ig.Hope it helps:))

Federal reserve decreases the required reserve ratio.

Banks have more money to lend

Money supply increases

Interest rates fall

Households and business take out more loans

Purchases and investments increases.

There are two types of monetary policies, Expansionary and Contractionary.

The government decides the monetary policy based on the economy of a country. The government will have expansionary monetary policy when it requires more money in the economy. Interest rates are lowered and money supply is increased. This results increase in Gross Domestic products of the country and the economy strengthens.

Learn more at https://brainly.com/question/24325773

Answer:

Below is the answer

Explanation:

Each of the three choices is tasteless, exhibitionist, juvenile, and dangerous.  John should do none of them.

Encountering a news crew, there's no reason for John to call attention to himself in a childish way, or interfere with their work in any way.

What he should do is:

==> Slow down

==> Pass the scene cautiously

==> Resume his normal, legal speed quietly, in case the crew happens to be recording audio at the moment.

Mysteriously, this course of action is nowhere to be found among the choices listed.

Answer:

all three options :)

Explanation:

cuz merica

Answer:

216

you have to change the meters per second to meters per minute, so you multiply .12 by 60 and get 7.2, then you multiply 7.2 meters per minute by 30 minutes and get 216

Answer:

Infrasound vs. Ultrasound: Infrasound is sound that is below the lower limit of human hearing, below 20 Hz, and ultrasound is above the upper limit of human hearing, above 20,000 Hz.  Individuals use infrasound - this recurrence run for checking seismic tremors and volcanoes, graphing rock and oil developments underneath the earth. Infrasound is described by a capacity to get around hindrances with little scattering.  

For instance, a few creatures, for example, whales, elephants and giraffes convey utilizing infrasound over significant distances. Torrential slides, volcanoes, seismic tremors, sea waves, water falls and meteors produce infrasonic waves. Symptomatic ultrasound, additionally called sonography or demonstrative clinical sonography, is an imaging technique that utilizes high-recurrence sound waves to create pictures of structures inside your body. The pictures can give important data to diagnosing and treating an assortment of ailments and conditions.

Explanation:

idk how many words this is but its a start for u to add on to and i hope this helps and its in my own words - pls mark me brainiest

Answer:

5×10⁻⁸ m²

Explanation:

I assume you mean the resistivity of the material is 50×10⁻⁸ Ωm.

R = ρL/A

10 Ω = (50×10⁻⁸ Ωm) (1 m) / A

A = 5×10⁻⁸ m²

12. C

13. A

14. B

15. D

16. D

17. B

Answer:

Explanation:

Given mg = 4N .

m = 4 / g

At the bottom of the swing let centripetal acceleration be a

T - mg = ma

9 - 4 = ma

5 = 4 a  / g

a =  5g / 4

Explanation:

2. Sum the torques about the fulcrum.

(450 N) (2 m) − (350 N) x = 0

x = 2.57 m

3. Sum the torques about the fulcrum.

(3600 N) (0.20 m) − F (0.90 m) = 0

F = 800 N

Mechanical advantage is the ratio between the load force and effort force.

MA = 3600 N / 800 N

MA = 4.5

Velocity ratio is the mechanical advantage divided by efficiency.  Assuming the lever is 100% efficient:

VR = 4.5 / 1

VR = 4.5

4. Mechanical advantage is the ratio between the load force and effort force.

MA = 900 N / 600 N

MA = 1.5

The velocity ratio is the distance moved by the effort divided by the distance moved by the load.  For a 3 pulley system, VR = 3.

Efficiency is mechanical advantage divided by velocity ratio.

e = 1.5 / 3

e = 0.50

5. Sum the torques about the fulcrum.

(-300 N) (0.10 m) + F (0.03 m) = 0

F = 1000 N

Answer:

Water waves are an example of waves that involve a combination of both longitudinal and transverse motions. As a wave travels through the waver, the particles travel in clockwise circles. The radius of the circles decreases as the depth into the water increases.

Answer:

The final temperature is 31.94°

Explanation:

The mass of the water in the container m₁ = 200 g = 0.2 kg

The initial temperature of the water,  T₁₁ = 30°C

The mass of the iron, m₂ = 200 g = 0.2 kg

The temperature of the iron T₂₁= 50°C is immersed in the water,

The specific heat capacity of the water, c₁ = 4200 J/(kg·°C)

The specific heat capacity of the iron, c₂ = 450 J/(kg·°C)

Heat capacity relation is given by the formula;

Heat capacity Q = Mass, m × Specific heat capacity, c × Temperature change, (T₂ - T₁)

Given that energy can neither be created nor destroyed, and with the assumption that all the heat lost by the nail is gained by the water we have;

Heat lost by iron nail = Heat gained by the  water

m₁ × c₁ × (T₂ - T₁₁) = m₂ × c₂ × (T₂₁ - T₂)

Where, T₂ is the final temperature

0.2 kg × 4200 J/(kg·°C) × (T₂ - 30) = 0.2 kg × 450 J/(kg·°C) × (50° - T₂)

840·T₂ - 25200 = 4500 - 90·T₂

4500 + 25200 = 840·T₂ + 90·T₂

29700 = 930·T₂

T₂ = 29700/930 = 31.94°.

The final temperature = 31.94°.

Answer: C

Explanation:

Since bulb B is burnt out, the wires can't transfer to bulb A, so that's why bulb A will burn out.

If I get it wrong, sorry. Im still learning.

Answer:

5.3333 sec

Explanation:

initial speed: u = 108km/hr or 30 m/s

final speed: v = 0m/s

distance travelled: s = 80m

time the car took to stop: = t sec

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

a = ([tex]v^{2} - u^{2}[/tex])/2s

a = (0-900)/160

a = -5.625 [tex]ms^{-2}[/tex]

v = u + at,

t = (v - u)/a

t= (0 - 30)/(-5.625)

t = 5.3333 sec

Answer:

Explanation:

In all works of life science can be applied, in-fact science has already been applied already, even in the humanities, social sciences and art related studies sciences is being applied,

    Furthermore, the application of science and technology knows no boundaries, and as science is advancing day by day, expanding to new frontiers and breaking new limits so is it application to all works of life and relevance everyday.

Answer:

12 i. The work done by Wale = 107.910 kJ

The work done by Lekan = 117.720 kJ

Total work done = 225.36 kJ

ii. Wale's power =  4.3164 kW

Lekan's power = 3.924 kW

Wale has more power and is more powerful than Lekan

13. 313.92 N

Explanation:

i. The work done, W = Force, F × Distance moved by the force, D

The given parameters are

The mass of Wale = 55 kg

The mass of Lekan = 60 kg

The acceleration due to gravity, g =9.81 m/s²

The motion force of Wale and Lekan are;

Motion force of Wale = 9.81 × 55 = 539.55 N

Motion force of Lekan = 9.81 × 60 = 588.6 N

The work done by Wale = 539.55 × 200 = 107910 J = 107.910 kJ

The work done by Lekan= 588.6 × 200 = 117720 J = 117.720 kJ

107910 + 117720 =225630 J = 225.36 kJ

ii. Power = Work done/time

Wale finished the race in 25 s, therefore, his power = 107910/25 = 4316.4 W

Lekan finished the race in 30 s, therefore, his power = 117720/30 = 3924 W

Wale has more power and is more powerful than Lekan

13. The velocity ratio = 5

V. R. = Distance moved by effort/(Distance moved by load)

Efficiency = 80%

Work done by effort = x

Work done by machine = Efficiency × Work done by effort  = 0.8 × x

Distance moved by effort, E = V. R. × Distance moved by load, D = 5 × D

Work done by effort = Force × Distance moved = 200×9.81× E

Work done by effort = 1962×E = 1962×E = 1962×5×D

Work done by machine = 1962 × D, when D = 1, we have;

0.8 × 1962×1 = 1569.6 J

Work done by effort = Force × Distance moved

Work done by effort = Force × 5×D = Force × 5 (D = 1)

From the principle of conservation of energy, we have;

Energy is neither created nor destroyed

Therefore

Work done by effort = Force × 5 = 1569.6 J

Force = 1569.6 /5 = 313.92 N.

Answer:

47.17 m

Explanation:

From the diagram of the question attached, The length of the legs are 25 m and 40 m . This legs form a right angle triangle with the length of the swimming course (L).

Pythagoras theorem states that for a right angle triangle with hypotenuse a and legs b and c, then:

a² = b² + c²

In the triangle, the length of the swimming course (L) is the hypotenuse and the two legs are 25 m and 40 m. Using Pythagoras:

L² = 25² + 40²

L² = 625 + 1600

L² = 2225

L = √2225

L = 47.17 m

Answer:

114m

Explanation:

s=ut + 1/2 at^2

s=23 m/s ×3s + 1/2×3×3s^2×10m/s^2

= (69+45)m

= 114m

Answer:

The dust present in the clouds.

Explanation:

The complicated composition molecules that can be found in space are generally associated with clouds of dust. The significant amount of dust in these clouds provides protection not only for these molecules, but for any body that makes up or is associated with dust clouds.

It is exactly this dust that protects the molecules against the action of ultraviolet rays.

Answer:

Dx/dt  = 4,8 f/s

Explanation:

The ladder placed against a wall, and the ground formed a right triangle

with x and h the legs and L the hypothenuse

Then

L² = x² + h²          (1)

L = 26 f

Taking differentials on both sides of the equation we get

0  = 2x Dx/dt  + 2h Dh/dt    (1)

In this equation

x = 10   distance between the bottom of the ladder and the when we need to find, the rate of the ladder moving away from the wall

Dx/dt is the rate we are looking for

h = ?    The height of the ladder when  x = 10

As    L²  =  x²  + h²

h²  =  L²  -  x²

h²  =  (26)²  - (10)²

h²  =  676  -  100

h²  = 576

h = 24 f

Then equation (1)

0  = 2x Dx/dt  + 2h Dh/dt

2xDx/dt  = -  2h Dh/dt

10 Dx/dt  = - 24 ( -2 )      ( Note the movement of the ladder is downwards)

Dx/dt  =  48/10

Dx/dt  = 4,8 f/s

Answer:

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Speed = Distance/time

Speed = 800/40

Speed = 20 metre per second

Answer:

The velocity and direction after 1 second is 8.1 m/s downwards

Explanation:

The equation of motion for an object in free fall can be written as follows;

v = u + g×t

Where;

v = The final velocity of the object

u = The initial velocity of the object = 0 m/s

g = The acceleration due to gravity = 9.81 m/s²

The velocity after one second is given by the velocity equation as follows;

v = 0 + 9.81 m/s² * 1 s = 9.81 m/s

The direction of the is downwards due to the attraction by the Earth's gravitational field which acts towards the Earth's center

Therefore, the velocity and direction after 1 second is 8.1 m/s downwards.