prove first equation of motion​

Answer:

2.0km/h.

Explanation:

iiiiijjjjjij

DL: Activity 2.3 Resistance

Complete the questions based on the Resistance presentation.

a. All resistors ___________ or _____________ the flow of electrons.

b. As resistance __________________ current _______________________

a) limits or opposes

b) increases, decreases

Resistors are electrical devices used to resist, limit, oppose or hinder the flow of electrons in a circuit. This resistance causes a reduction in current and an increase in voltage in the circuit. In order words, as resistance increases, the current decreases and voltage increases.

This was further stated by Ohm's law that states that as long as the resistance in a wire/conductor remains constant, the voltage across it is directly proportional to the current flowing through a conductor. i.e

V = IR

Where;

R = constant called resistance

I = current flowing through the wire

V = voltage across the wire

Answer:

The sign of work will be negative.

Explanation:

The work of the system is given by:

[tex] W = _{V_{i}}^{V_{f}}\int pdV = p(V_{f} - V_{i}) [/tex]

Where:

[tex]V_{f}[/tex]: is the final volume = 31 L

[tex]V_{i}[/tex]: is the initial volume = 63 L

p: is the pressure

Even though we do not have the pressure value, by knowing the values of the initial and final volume we can predict the sign of work.            

[tex] W = p(V_{f} - V_{i}) = p(31 L - 63 L) = -32p [/tex]

Therefore, the sign of work will be negative.

I hope it helps you!

Answer: Minimum speed needed by the Olympic champion at launch if he was traveling at 6.8 m/s at the top of the arc is 11.65 m/s.

Explanation:

Velocity is only in horizontal direction at the top most point which is similar to the velocity in the horizontal direction at the time of launch.

Now, according to the law of conservation of energy the formula used is as follows.

[tex]mgh = \frac{1}{2} mv^{2}_{y}\\v_{y} = \sqrt{2gh}\\= \sqrt{2 \times 9.8 m/s^{2} \times 1.2}\\= 4.85 m/s[/tex]

As speed at which the person is travelling was 6.8 m/s. Hence, the initial velocity will be calculated as follows.

[tex]v = \sqrt{v^{2}_{x} + v^{2}_{y}}\\= \sqrt{(6.8)^{2} + (4.85 m/s)^{2}}\\= 11.65 m/s[/tex]

Thus, we can conclude that minimum speed needed by the Olympic champion at launch if he was traveling at 6.8 m/s at the top of the arc is 11.65 m/s.

Answer:

The correct answer is - 6.49 × 10^3 mm.

Explanation:

The correct scientific notation of the given subtraction problem is:

6.94 × 10^3 mm - 4.5 × 10^2 mm = _____.

The correct number of significant digits is

a. 6.94 × 10^3 mm = 3

b. 4.5 × 10^2 mm = 2

So subtracting the 6.94 × 10^3 mm - 4.5 × 10^2 mm

= 6940 - 450

= 6.49× 10^3 mm.

Answer:

6.5x 10^3 mm

Explanation:

Answer:

a yard

Explanation:

Answer:

3.416 m/s

Explanation:

Given that:

mass of cannonball [tex]m_A[/tex] = 72.0 kg

mass of performer [tex]m_B[/tex] = 65.0 kg

The horizontal component of the ball initially [tex]\mu_{xA}[/tex] = 6.50 m/s

the final velocity of the combined system v = ????

By applying the linear momentum of conservation:

[tex]m_A \mu_{xA}+m_B \mu_{xB} = (m_A+m_B) v[/tex]

[tex]72.0 \ kg \times 6.50 \ m/s+65.0 \ kg \times 0 = (72.0 \ kg+65.0 \ kg) v[/tex]

[tex]468 kg m/s + 0 = (137 kg)v[/tex]

[tex]v = \dfrac{468\ kg m/s }{137 \ kg}[/tex]

v = 3.416 m/s

Answer:

According to the parallelogram law of vector addition if two vectors act along two adjacent sides of a parallelogram(having magnitude equal to the length of the sides) both pointing away from the common vertex, then the resultant is represented by the diagonal of the parallelogram passing through the same common vertex

Explanation:

Answer:

c

Explanation:

Answer:C

Explanation:

Hey there!

The energy that is stored in food is called CHEMICAL ENERGY

So, when humans/people eat foods their bodies transfigure the energy that is stored which is known as the calories.

Whereas the chains (bonds) in the middle of the atoms in the food humans eat that break up the check mal reactions that has been taken into place and newer compounds will be created. Each food that you eat stores unlikeable amounts of energy

Answer: Chemical energy

Good luck on your assignment and enjoy your day!

~Amphitrite1040:)

Answer:

correct answer is c

The balls will hit the ground simultaneously

Explanation:

This is an exercise in kinematics, let's analyze each case separately

Carla. Holds the ball at an initial height y = 1,5m and releases the ball therefore its initial velocity is zero v₀ = 0

          y = y₀ + v₀ t - ½ gt²

          0 = y₀ + 0 - ½ g t²

          t = [tex]\sqrt{\frac{2y_o}{g} }[/tex]

Daniel This holds the ball at I = 1.5 m and releases the ball as it passes by Carla, therefore the initial velocity is

horizontal vox = 40 mph

vertical   v_{oy} = 0

           y = y_{oy}I + v_{oy} t - ½ g t²

            0 = y_{oy} + 0 - ½ g t²

            t = [tex]\sqrt{\frac{2 y_o}{g} }[/tex]

we can see that they both spend the same time reaching the ground

           t = [tex]\sqrt{2 \ 1.5 / 9.8}[/tex]

           t = 0.55 s

The correct answer is c

The balls will hit the ground simultaneously

This question is in complete, the missing table is uploaded along this answer.

Answer:

the maximum possible kinetic energy K of the electrons emitted from this new surface is 4.9 eV

Explanation:

Given the data in the question;

copper K = 2.7 eV

If the copper is replaced with a piece of sodium ( Na )

the maximum possible kinetic energy K of the electrons emitted from this new surface = ?

we know that;

Kinetic energy of emitted electrons can be written as;

K = hv - hv₀

where v is frequency, h is Plank's constant, and hv₀ is work function of metal

so lets make hv the subject of formula;

hv = K + hv₀

from the table below, work function of copper is 4.5 eV

so we substitute

hv = 2.7 eV + 4.5 eV

hv = 7.2 eV

Now, If the copper is replaced with a piece of sodium ( Na )

we have;

K = hv - hv₀

from the table below, work function of Sodium is 2.3 eV

so we substitute

K = 7.2 eV - 2.3 eV

K = 4.9 eV

Therefore,  the maximum possible kinetic energy K of the electrons emitted from this new surface is 4.9 eV

Answer:

20J

Explanation:

[tex]KE = \frac{1}{2} mv^{2} = \frac{1}{2} (10)(2)^{2} =20J[/tex]

Answer:

[tex]W_m=183.495N[/tex]

Explanation:

From the question we are told that:

Weight [tex]W=248Ibs[/tex]

Mass of Weight  [tex]m= 248*0.453[/tex]

                          [tex]m=112.344kg[/tex]

Generally the acceleration due to gravity on the Moon is one-sixth that on Earth.

Therefore

The equation for Weight on Moon is given as

 [tex]W_m=m*g/6[/tex]

 [tex]W_m=122.344*\frac{9.8}{6}[/tex]

 [tex]W_m=183.495N[/tex]

Answer:

F ’= 40.9 lb

Explanation:

The weight of a body is the attraction of the Earth on the body

          F = [tex]G \frac{m M_e}{R_e^2}[/tex]

          F = mg

          m = F / g

          m = 248/32

         m = 7.75 slug

The weight of the body on the moon is the attraction of the body for the satellite

         F ’= [tex]G \frac{mM}{R^2}[/tex]

from the tables the mass and radius of the moon are M = 7.34 10²² kg and R = 1.74 10⁶ m

let's reduce the mass to the SI system

         m = 7.75 slug (14.59 kg / 1 slug) = 113 kg

         F ’= 6.67 10⁻¹¹ 113 7.34 10²² / (1.74 10⁶) ²

         F ’= 1.82 10² N

         F ’= 1.82 10² N (0.2248 lb / 1 N)

         F ’= 40.9 lb

Answer:

correct answer is b

Explanation:

The frequency of a wave depends on the properties of medium density and the elasticity properties change the amplitude depends on the energy carried by the wave, that is, the amplitude is proportional to the height of the wave (oscillation).

Consequently the amplitude of independent of the frequency because it depends on different factors.

Therefore when changing the amplitude the wavelength remains constant

the correct answer is b

Answer:

75%

Explanation:

We'll begin by calculating the final volume of the gas. This can be obtained as follow:

Initial volume (V₁) = V

Initial temperature (T₁) = T

Initial pressure (P₁) = P

Final pressure (P₂) = 2P

Final temperature (T₂) = ½T

Final volume (V₂) =?

P₁V₁/T₁ = P₂V₂/T₂

PV/T = 2P × V₂ / ½T

Cross multiply

T × 2P × V₂ = PV × ½T

T × 2P × V₂ = PV × ½T

Divide both side by T × 2P

V₂ = (PV × ½T) / T × 2P

V₂ = ¼V

Next, we shall determine the absolute change in the volume of the gas. This can be obtained as follow:

Initial volume (V₁) = V

Final volume (V₂) = ¼V

Absolute change in volume |ΔV| =?

|ΔV| = |V₂ – V₁|

|ΔV| = |¼V – V|

|ΔV| = |0.25V – V|

|ΔV| = 0.75V

Finally, we shall determine percentage change in the volume of the gas. This can be obtained as follow:

Initial volume (V₁) = V

Absolute change in volume |ΔV| = 0.75V

Percentage change =?

Percentage change = |ΔV| / V × 100

Percentage change = 0.75V / V × 100

Percentage change = 0.75 × 100

Percentage change = 75%

Thus, the percentage change in the volume of the gas is 75%

Answer:

C: Mass of body

Explanation:

Upthrust is defined as the upward force that a liquid will exert on a body floating atop it.

Now, Formula for upthrust is;

Upthrust = density of liquid × volume of the body × acceleration due to gravity.

From the formula, we can see that upthrust depends on density, volume and acceleration due to gravity.

Thus, looking at the options, the one that doesn't apply is mass of body.

Answer:

Explanation:

GPE =weight * height

       = 2000*(25-20)

      =  10000 J

Gain of Gravitation Potential energy  = 10,000 J

It is the energy acquired by an object due to a change in its position when it is present in a gravitational  field .

To calculate gravitational potential energy at height h , formula used is                                                                  =                     m g h where m = mass of the body

                                            g = acceleration due to gravity

                                            h = height from the ground

Gain of Gravitation Potential energy  = mg(h2 - h1 )      h2 = final height

                                                                             h1 = initial height

                                                = 2000  (25 -20)    (since , mg =weight)

Gain of Gravitation Potential energy  = 10,000 J

Learn more about Gravitation Potential energy  :

https://brainly.com/question/3884855?referrer=searchResults

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Answer:

Impulse = 1000 Ns

Explanation:

Given the following data;

Force of collision = 1000 kg•m/s.

Time = 1 seconds

To find the impulse;

Mathematically, the impulse experienced by an object or body is given by the formula;

Impulse = force * time

Substituting into the formula, we have;

Impulse = 1000 * 1

Impulse = 1000 Ns

Answer:

A wave with a frequency of 60 hertz will have 60 successive wave crests occurring every second

Explanation:

A crest is the highest point the medium rises to in a wave. That means that the crest is a point on the wave where the displacement is at a maximum.

Frequency is the number of oscillations of a wave in one second. Hence, frequency of a wave is the number of successive crests occurring in a second.

Therefore a wave with a frequency of 60 hertz will have 60 successive wave crests occurring every second.

Answer:

the inductive reactance of the coil is 1335.35 Ω

Explanation:

Given;

inductance of the coil, L = 250 mH = 0.25 H

effective current through the coil, I = 5 mA

frequency of the coil, f = 850 Hz

The inductive reactance of the coil is calculated as;

[tex]X_l = \omega L = 2\pi f L\\\\X_l = 2\pi \times 850 \times 0.25\\\\X_l = 1335.35 \ ohms[/tex]

Therefore, the inductive reactance of the coil is 1335.35 Ω

Answer:

120N Hacia arriba

Answer: A. The acceleration of an object is determined by its mass and the net force acting on it.

Explanation:

Newton's second law of motion explains that the acceleration of an object will depend on two vital variables which are the mass of the object and the net force that's acting on it.

It should be noted that the acceleration of the object directly depend on the net force while it depends inversely on the mass. Therefore, when the force that's acting on such object is increased, then the acceleration will increase as well. On the other hand, when there is an increase in mass, there'll be a reduction in the acceleration.

Answer:

carbon dioxide (CO2)

Explanation:

the burning or combustion of these fossil fuels creates gases that are released into the atmosphere. Of these gases, carbon dioxide (CO2) is the most common and is the gas most responsible for exacerbating the green- house effect that is changing global climate patterns.

Answer:

P = 0.25 W

Explanation:

Given that,

The emf of the battry, E = 2 V

The resistance of a bulb, R = 16 ohms

We need to find the power delivered to the bulb. We know that, the formula for the power delivered is given by :

[tex]P=\dfrac{V^2}{R}\\\\P=\dfrac{2^2}{16}\\\\=0.25\ W[/tex]

So, 0.25 W power is delivered to the bulb.

Answer:

[tex]\boxed {\boxed {\sf a \approx 0.4 \ m/s^2}}[/tex]

Explanation:

According to Newton's Second Law of Motion, force is the product of mass and acceleration.

[tex]F= m \times a[/tex]

The net force is 5 Newtons and the mass is 13 kilograms. Let's convert the units for force to make the problem and unit cancellation easier.

Now we know the values for 2 variables:

Substitute the values into the formula.

[tex]5 \ kg *m/s^2 = 13 \ kg * a[/tex]

Since we are solving for the accleration we must isolate the variable, a. It is being multiplied by 13 kilograms and the inverse of multiplication is division. Divide both sides by 13 kg

[tex]\frac {5 \ kg *m/s^2}{13 \ kg}= \frac{ 13 \ kg *a}{13 \ kg}[/tex]

[tex]\frac {5 \ kg *m/s^2}{13 \ kg}=a[/tex]

The units of kilograms (kg) cancel.

[tex]\frac {5 m/s^2}{13 }=a[/tex]

[tex]0.384615385\ m/s^2=a[/tex]

The original measurements of force and mass ( 5 and 13) have 1 and 2 significant figures. We must round our answer to the least number of sig figs: 1.

For the number we found, that is the tenths place. The 8 in the hundredth place (0.384615385) tells us to round the 3 up to a 4.

[tex]0.4 \ m/s^2 \approx a[/tex]

The acceleration is approximately 0.4 meters per square second.

P = F / A

P = 2400 / 4

P = 24 × 100 / 4

P = 6 × 100

P = 600 N/m^2