Part
A block of mass 2 kg is acted upon by two forces: 3 N (directed to the left) and 4 N (directed to the right). What can you say about the blocks motion?

Answer:

Explanation:

The energy of a photon is given by the Planck relation

          E = h f

the speed of light is related to wavelength and frequency

          c = λ f

           f- c /λ

we substitute

          E = h c /λ

let's calculate

          E = 6.63 10-34 3 10⁸ / 550 10-9

          E = 3.616 10-19 J

let's reduce to eV

          E = 3.616 10-19 J (1 eV / 1.6 10-19)

          E = 2.26 eV

Answer:

[tex]v=4.32m/s[/tex]

Explanation:

From the question we are told that:

Accelerates at rate of [tex]1.2m/s^2[/tex]

Acceleration time [tex]t_a=4.5secs[/tex]

Velocity time 1 [tex]t_{v1}=12.1secs[/tex]

Deceleration distance [tex]d_a=87meters[/tex]

Generally the Newton's equation for motion is mathematically given by

 [tex]V=at[/tex]

 [tex]v=(1.2)3.6[/tex]

 [tex]v=4.32m/s[/tex]

Answer:

dβ = 70. 77 dβ

Explanation:

The intensity of sound in decibels is

         dβ = 10 log I/I₀

let's look for the intensity of this signal

         I / I₀ = 10 dβ/10

         I / I₀ = 3.981 10⁶

the threshold intensity of sound for humans is I₀ = 1 10⁻¹² W / m²

         I = 3.981 10 ⁶ 1 10⁻¹²

         I = 3,981 10⁻⁶ W / m²

It is indicated that 3 cornets are placed in the circle, for which total intensity is

        I_total - 3 I

        I_total = 3  3,981 10⁻⁶

        I_total = 11,943 10⁻⁶ W / m²

let's reduce to decibels

      dβ = 10 log (11,943 10⁻⁶/1 10⁻¹²)

      dβ = 10  7.077

      dβ = 70. 77 dβ

Answer:

Following are the solution to the given question:

Explanation:

Its strength from both charges is equivalent or identical. The power is equal. And it is passed down

[tex]F=\frac{kq_1q_2}{r^2}[/tex]

Therefore, the extent doesn't rely on the fact that charges are the same or different. Newton's third law complies with Electrostatic Charges due to a couple of charges. They are similar in magnitude, and they're in the other way.

[tex]|F_{12}| = |F_{21}|[/tex]

Answer:

The answer is "0.2711  m/s".

Explanation:

Potential energy = Kinetic energy + Potential energy

[tex]m_1 gh =\frac{1}{2} m_1v^2 +\frac{1}{2} m_2v^2 + \frac{1}{2} I\omega^2 + m_1gh\\\\[/tex]

[tex](m_1- m_2)gh =\frac{1}{2} m_1v^2 +\frac{1}{2} m_2v^2 +\frac{1}{2} I\omega^2\\\\2(m_1 - m_2)gh = m_1v^2 + m_1v^2 + I\omega^2\\\\solid \ disk (I) = \frac{1}{2} \ \ M r^2 \\\\[/tex]

When there is no slipping, \omega  =\frac{ v]{r}\\\\  

[tex]2(m_1 - m_2)gh = m_1v^2 + m_2v^2 + (\frac{1}{2} Mr^2) (\frac{v}{r})^2\\\\2(m_1 -m_2)gh = m_1v^2 + m_2v^2 + \frac{1}{2} Mv^2\\\\4(m_1 -m_2)gh = 2m_1v^2 + 2m_2v^2 + Mv^2\\\\4(m_1 - m_2)gh = (2m_1 + 2m_2 + M) v^2\\\\[/tex]

[tex]v^2 = \frac{4(m_1 - m_2)gh}{(2m_1 + 2m_2 + M)}v[/tex]

[tex]v^2 = \frac{4 (0.25 \ kg - 0.20 \ kg) (9.8 \frac{m}{s^2}) (0.21 m)}{ (2 \times 0.25 kg + 2 \times 0.20 kg + 0.50 kg)}[/tex]

[tex]=\frac{0.1029}{1.4} \ \ \frac{m^2}{s^2}\\\\=0.0735\ \ \frac{m^2}{s^2}\\\\= 0.2711 \ \frac{m}{s}[/tex]

Answer:

673km

Explanation:

Answer:

a)    F = 35.7 N, b)   W = 846.7 J, c)   W = - 846.9 J, d) W=0

Explanation:

a) For this exercise let's use Newton's second law, let's set a reference frame with the x-axis horizontally

let's break down the pushing force.

        cos (-23,7) = Fₓ / F

        sin (-237) = F_y / F

        Fₓ = F cos 23.7 = F 0.916

        F_y = F sin (-23.7) = - F 0.402

Y axis  

       N- W - F_y = 0

       N = W + F 0.402

X axis

       Fₓ - fr = 0

       F 0.916 = fr

       F = fr / 0.916

       F = 32.7 / 0.916

       F = 35.7 N

It is asked to calculate several jobs

b) the work of the pushing force

       W = fx x

       W = 35.7 cos 23.7 25.9

       W = 846.7 J

c) friction force work

        W = F x cos tea

friction force opposes movement

        W = - fr x

         W = - 32.7 25.9

         W = - 846.9 J

d) The work of the force would gravitate, as the displacement and the force of gravity are at 90º, the work is zero

          W = 0

Answer:

At the earth's surface  g = G M / R^2        where G is the gravitational constant

at H       g1 = G M / (R + H)^2         using Gauss' theorem for enclosed mass

g1 = G M / (R^2 + 2 R H)    ignoring H^2 as it is small compared to R^2

g / g1 = (R^2 + 2 R H) / R^2 = 1 + 2 R H

g = g1 + 2 R H g1

g1 - g = - 2 R H     or H = (g1 - g) / 2 R

-A solid has a definite shape and volume.

-Solids in general have higher density.

-In solids, intermolecular forces are strong.

Answer:

Fission is used in nuclear power reactors since it can be controlled, while fusion is not utilized to produce power since the reaction is not easily controlled and is expensive to create the needed conditions for a fusion reaction.

Explanation:

Answer:

Hello There!!

Explanation:

I think it is A. Fusion requires very high pressure and temperature. Sorry if I am wrong.

hope this helps,have a great day!!

~Pinky~

Answer:

Put the 2 light bulbs in series.

Explanation:

The resistance will be the greatest if you hook up the light bulb in series, and since resistance and current are inversely proportional, the current will be the least as well.

Answer:

36 ohm

Explanation:

Given :

P=400 W

V=120V

Now,

[tex]P=\frac{V^{2} }{R} \\400=\frac{120^{2} }{R} \\400R=14400\\R=\frac{14400}{400} \\R=36 ohm[/tex]

Therefore, resistance of the drill will be 36 ohm

Answer:

Explanation:

Slope is rise over run and, consequently, it is also the tangent ratio. the side measuring 2 is the height of the right triangle that is formed by the inclined plane (the hypotenuse), the height, and the base (the ground or surface that the plane is sitting on). If we use the tangent ratio,

[tex]tan\theta=\frac{2}{6}=\frac{1}{3}[/tex] so

[tex]tan^{-1}(\frac{1}{3})=\theta[/tex] so

θ = 18.4 which is also the angle that makes that slope.

Answer:

The answer is:-

Explanation:

An electron emitted from an atom by enteraction with an photon, especially an eclectron emitted from a solid surface by the action of light.

Answer: See explanation

Explanation:

Climate change, is also referred to as global warming, and it simply means the rise in Earth's average surface temperature.

Effects of climate change include rising sea levels, heat waves, drought, storms, etc.

Extreme heat events is dangerous to the health of both animals and humans. For human beings, it can bring about increase in heat- related illness, weakness, heat stroke and excessive water consumption.

For animals, it can lead to struggling of the animals in losing their excess body heat by evaporation. Other effects include panting, loss of appetite, increased drinking, difficulty breathing, anxious behaviour, and weakness.

Answer:

Option C. 210 J.

Explanation:

From the question given above, the following data were obtained:

Mass (m) = 0.75 Kg

Height (h) = 12 m

Velocity (v) = 18 m/s

Acceleration due to gravity (g) = 9.8 m/s²

Total Mechanical energy (ME) =?

Next, we shall determine the potential energy of the plane. This can be obtained as follow:

Mass (m) = 0.75 Kg

Height (h) = 12 m

Acceleration due to gravity (g) = 9.8 m/s²

Potential energy (PE) =?

PE = mgh

PE = 0.75 × 9.8 × 12

PE = 88.2 J

Next, we shall determine the kinetic energy of the plane. This can be obtained as follow:

Mass (m) = 0.75 Kg

Velocity (v) = 18 m/s

Kinetic energy (KE) =?

KE = ½mv²

KE = ½ × 0.75 × 18²

KE = ½ × 0.75 × 324

KE = 121.5 J

Finally, we shall determine the total mechanical energy of the plane. This can be obtained as follow:

Potential energy (PE) = 88.2 J

Kinetic energy (KE) = 121.5 J

Total Mechanical energy (ME) =?

ME = PE + KE

ME = 88.2 + 121.5

ME = 209.7 J

ME ≈ 210 J

Therefore, the total mechanical energy of the plane is 210 J.

Explanation:

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Answer:

1.2

Explanation:

Answer:

[tex]68.0^{\circ}[/tex]

Explanation:

A projectile's vertical velocity at the top of its flight path must be zero, therefore the speed at the top of the trajectory must be referring to the object's horizontal velocity. Since there are exactly zero horizontal forces acting on the object, its horizontal velocity will remain the exact same throughout the entire launch. Thus, the horizontal component of the initial launch must be  45 meters per second, and we have the following equation using basic trigonometry for a right triangle:

Let [tex]\theta[/tex] be the unknown angle above the horizontal.

[tex]\cos \theta=\frac{45}{120},\\\theta=\arccos(\frac{45}{120})=67.97568716^{\circ}\approx \boxed{68.0^{\circ}}[/tex]

Answer:

Yes

Explanation:

Answer:

Explanation:

1. The waves in which the partciles of medium vibrates in the same direction of propagation of wave, are called longitudinal waves.

The waves in which the partciles of medium vibrates in the perpendicular direction of propagation of wave, are called transverse waves.

2. Period, T = 0.03 s

The frequency is given by the reciprocal of the period.

[tex]f=\frac{1}{T}\\\\f =\frac{1}{0.03}\\\\f = 33.3 Hz[/tex]

1. Transverse waves carry molecules at right angles to the direction in which the wave travels. Within a cycle, molecules move from their normal position to the highest position, back through the normal position to the lowest point, and then back to the normal position. The molecules retain their horizontal positions while vibrating vertically. Amplitude is measured at right angles to the direction of the travel of the wave. Wavelength can be represented as the distance between any two molecules in phase with each other, such as the two nearest molecules at the crests of the wave.

Longitudinal waves carry molecules parallel to the direction in which the wave travels. Within a cycle, a molecule travels in the same direction as the wave (from normal position to its most distant point on one side of its normal position), changes direction, moves back through its normal position to the opposite side of its normal position at a point that corresponds, and then returns to its normal position. The molecules don’t all move at the same time; some remain stationary as others go through a vibrating motion. Compressions and rarefactions occur here. Amplitude is measured parallel to the direction of the wave. Wavelength may be represented as the distance between the two nearest molecules that didn’t vibrate, the two nearest molecules at maximum compression, or the two nearest molecules at maximum rarefaction.

2. f = 1⁄T  

f = 1⁄0.03

f = 33. 3 Hz

3. The first wave has a frequency of 33.3 Hz:

f1 = 1⁄T1

f1 = 1⁄0.03

f1 = 33. 3 Hz

The second wave has a frequency of 4 Hz. f2 = 1⁄T2

f2 = 1⁄1⁄4

f2 = 1 ÷ 1⁄4

f2 = 1 × 4⁄1

f2 = 1⁄1 × 4⁄1

f2 = 4 Hz

Therefore, the first wave has a higher frequency.

4. v = I⁄T

v= 4.5⁄0.007

v = 642.9 m/s

5. Wavelength

Crest

Trough

Amplitude

Answer:

The magnitude of the friction force is also F.

Explanation:

By the second Newton's law, we know that:

F = m*a

Net force is equal to mass times acceleration.

Here, we know that the box moves with constant speed, thus, the box has no acceleration, then the net force applied to the box is zero.

Also, remember that the friction force is given by:

[tex]F_f = -\mu*W[/tex]

Where mu is the coefficient of friction, and this force opposes to the direction of motion (that coincides with the direction of our forward force, that is why this has a negative sign)

The net force will be equal to the sum of our two horizontal forces (as the weight is already canceled by the normal force)

[tex]F_{total} = F + F_f[/tex]

And this is equal to zero, because we know that the box is non-accelerated.

Then we must have that:

[tex]F_f = -F[/tex]

Then we can conclude that the magnitude of the friction force is F.

Answer:

the maximum vertical height the person in the cart can reach is 18.42 m

Explanation:

Given;

mass of the person, m₁ = 45 kg

mass of the cart, m₂ = 43 kg

velocity of the system, v = 19 m/s

let the maximum vertical height reached = h

Apply the principle of conservation mechanical energy;

[tex]P.E = K.E\\\\mgh_{max} = \frac{1}{2} mv^2_{max}\\\\gh_{max} = \frac{1}{2} v^2_{max}\\\\h_{max} = \frac{v_{max}^2}{2g} \\\\h_{max} = \frac{19^2}{2\times 9.8} \\\\h_{max} = 18.42 \ m[/tex]

Therefore, the maximum vertical height the person in the cart can reach is 18.42 m

Answer:

because thermometric liquid readily expands on heating or contracts on cooling even for a small difference in the temperature of the body.

Answer:

translate it to English plss

Answer:

The centripetal acceleration for the first radius; 2.0 m = 50 m/s²

The centripetal acceleration for the second radius; 4.0 m = 25 m/s²

The centripetal acceleration for the third radius; 6.0 m = 16.67 m/s²

The centripetal acceleration for the fourth radius; 8.0 m = 12.5 m/s²

The centripetal acceleration for the fifth radius; 10.0 m = 10 m/s²

Explanation:

Given;

mass of the object, m = 1 kg

velocity of the object, v = 10 m/s

different values of the radius, 2.0 m 4.0 m 6.0 m 8.0 m 10.0 m

The centripetal acceleration for the first radius; 2.0 m

[tex]a_c = \frac{v^2}{r} \\\\a_c_1= \frac{(10)^2}{2} \\\\a_c_1= 50 \ m/s^2[/tex]

The centripetal acceleration for the second radius; 4.0 m

[tex]a_c_2= \frac{(10)^2}{4} \\\\a_c_2= 25 \ m/s^2[/tex]

The centripetal acceleration for the third radius; 6.0 m

[tex]a_c_3= \frac{(10)^2}{6} \\\\a_c_3= 16.67 \ m/s^2[/tex]

The centripetal acceleration for the fourth radius; 8.0 m

[tex]a_c_4= \frac{(10)^2}{8} \\\\a_c_4= 12.5 \ m/s^2[/tex]

The centripetal acceleration for the fifth radius; 10.0 m

[tex]a_c_5= \frac{(10)^2}{10} \\\\a_c_5= 10 \ m/s^2[/tex]