. A cathode ray tube (CRT) is a device that produces a focused beam of electrons in a vacuum. The electrons strike a phosphor-coated glass screen at the end of the tube, which produces a bright spot of light. The position of the bright spot of light on the screen can be adjusted by deflecting the electrons with electrical fields, magnetic fields, or both. Although the CRT tube was once commonly found in televisions, computer displays, and oscilloscopes, newer appliances use a liquid crystal display (LCD) or plasma screen. You still may come across a CRT in your study of science. Consider a CRT with an electron beam average current of 25.00μA25.00μA . How many electrons strike the screen every minute?

Answer:

The larger object will have smaller  acceleration that the less massive object.

Explanation:

Generally force is mathematically represented as

      [tex]F = ma[/tex]

=>  [tex]m = \frac{F}{a }[/tex]

at constant  force  we have

     [tex]m \ \alpha \ \frac{1}{a}[/tex]

So if  m is  increasing a will be decreasing which means the object with the larger mass will have less acceleration

Complete question is;

Allyson and Adrian have decided to connect their ankles with a bungee cord; one end is tied to each person's ankle. The cord is 40 feet long, but can stretch up to 120 feet. They both start from the same location. Allyson moves 10 ft/sec and Adrian moves 9 ft/sec in the directions indicated. Adrian stops moving at time t = 5.5 sec, but Allyson keeps on moving 10 ft/sec in the indicated direction. (If a coordinate system is used, assume that the girls' starting position is located at

(x, y) = (0, 0) and that Allyson and Adrian move in the positive y and negative x directions, respectively. Let one unit equal one foot.)

Compute the length of the bungee cord at t = 7 seconds. (Round your answer to three decimal places.)

Answer:

Length of bungee cord = 85.734 ft

Explanation:

We are told that Adrian moves 9ft/sec. Thus, at 5.5 seconds, distance he moved is; 9 ft/sec × 5.5sec = 49.5 ft in the negative x (-x) direction. Therefore, the coordinate is (-49.5, 0).

Now, Allyson has moved 10ft/sec. Thus, at 7 seconds, distance he moved would be; 10 ft/sec x 7sec = 70 feet in the positive (+y) direction. Therefore, the coordinate is (0, 70).

Now, since they started from the origin, it means (0, 0) is a coordinate. Thus, we now have 3 coordinates which are; (0, 0), (0, 70) & (-49.5,0). These 3 coordinates would therefore combine to form a right triangle.

The hypotenuse is the distance between Allyson and Adrian.

Thus, from pythagoras theorem, we can find the distance between them which is same as the length of the cord.

Thus;

(-49.5)² + 70² = D².

D² = 2450.25 + 4900

D = √7350.25

D = 85.734 ft

Answer:

The duration  is  [tex]T  =72 \  years /tex]

Explanation:

From the question we are told that

   The  distance is  [tex]D  =  35 \ light-years = 35 *  9.46 *10^{15} = 3.311 *10^{17} \  m [/tex]

  Generally the time it would take for the message to get the the other civilization is mathematically represented as

         [tex]t =  \frac{D}{c}[/tex]

Here c  is the speed of light with the value  [tex]c =  3.08 *10^{8} \  m/s[/tex]

=>     [tex]t =  \frac{3.311 *10^{17} }{3.08 *10^{8}}[/tex]

=>     [tex]t =  1.075 *10^9 \ s[/tex]

converting to years

           [tex]t =  1.075 *10^9 *  3.17 *10^{-8} [/tex]

              [tex]t =  1.075 *10^9 *  3.17 *10^{-8} [/tex]

            [tex]t =  34 \ years [/tex]

Now the total time taken is mathematically represented as

      [tex]T  =  2*  t  +  2 + 2[/tex]

=>   [tex]T  =  2* 34  +  2 + 2[/tex]

=>   [tex]T  =72 \  years /tex]

Answer:

The answer is C. A force of 130 N moves it 22 m

The least amount of work done on a crate is when A force of 130 N moves it 22 m, the correct option is C.

The total amount of energy transferred when a force is applied to move an object through some distance

The work done is the multiplication of applied force with the displacement.

Work Done = Force * Displacement

The work done for option A is

                = 120*25= 3000 Nm

The work done for option B is

                 =115*26 = 2990 Nm

The work done for option C is

                 =130*22= 2860 Nm

The work don for option D is

                 = 125*27= 3375 Nm

Hence, the least amount of work is done on the crate when a force of 130 N moves it 22 m.

Learn more about work done

https://brainly.com/question/13662169

#SPJ5

Complete Question

A horizontal spring-mass system has low friction, spring stiffness 163 N/m, and mass 0.3 kg. The system is released with an initial compression of the spring of 12 cm and an initial speed of the mass of 3 m/s.

(a) What is the maximum stretch during the motion?

(b) What is the maximum speed during the motion?

m/s

(c) Now suppose that there is energy dissipation of 0.02 J per cycle of the spring-mass system. What is the average power input in watts required to maintain a steady oscillation?

Answer:

a

[tex]  x_m  =  0.18 \  m [/tex]

b

[tex]v_m  =  4.10 \  m/s[/tex]

c

[tex]P  = 0.085 \  W [/tex]

Explanation:

From the question we are told that

   The spring stiffness is  [tex]k =  163 \  N/m[/tex]

   The mass is  [tex]m  =  0.3 \  kg[/tex]

    The initial compression is  x  =  12 cm  =  0.12 m

     The initial  speed is  v =  3 m/s

Generally the total  energy stored in the spring at maximum stretch  is equivalent to the kinetic energy and the energy stored at the  initial  compression

This can be mathematically represented as

      [tex]E_{max}  =  K  +  E_{i}[/tex]

Here  [tex]E_{max}[/tex] is the energy  at maximum stretch which is mathematically represented as

     [tex]E_{max} =  \frac{1}{2} *  k  *  x_m^2[/tex]

and  

      [tex]E_{max} =  \frac{1}{2} *  k  *  x^2[/tex]

So

     [tex]\frac{1}{2} *  k  *  x_m^2 =  \frac{1}{2}m *  v^2   +  \frac{1}{2} *  k  *  x^2 [/tex]

=>  [tex]\frac{1}{2} *  163   *  x_m^2 =  \frac{1}{2}* 0.3 *   3^2   +  \frac{1}{2} *  163 *  0.12^2 [/tex]

=>  [tex]\frac{1}{2} *  163   *  x_m^2 =  \frac{1}{2}* 0.3 *   3^2   +  \frac{1}{2} *  163 *  0.12^2 [/tex]

=>  [tex]  x_m  =  0.18 \  m [/tex]

Gnerally the maximum kinetic energy when the stretch is  zero(i.e during motion), according to the law of energy conservation,  is equivalent to the kinetic energy when the spring is compressed plus the energy stored in the spring before it was released.    , this can be mathematically  represented as

[tex]\frac{1}{2} *  k  *  x^2  + \frac{1}{2} *  m *  v^2  =  \frac{1}{2} * m * v_m ^2[/tex]

Here [tex]v_m[/tex] is the maximum velocity when the stretch is zero

So  

   [tex]0.5 *  163   *  0.12^2  + \frac{1}{2} *  0.3 * 3^2  =  \frac{1}{2} * 0.3 * v_m ^2[/tex]

=>   [tex]v_m  =  4.10 \  m/s[/tex]

Generally the  period of the spring is mathematically represented as  

     [tex]T  =  2 *  \pi  *  \sqrt{\frac{m}{k} }[/tex]

=>   [tex]T  =  2 *  3.142 *  \sqrt{\frac{0.3}{163} }[/tex]

=>   [tex]T  =   0.2696 \  s [/tex]

From the question we are told that the energy is  0.02 J

Generally the power is

       [tex]P  =  \frac{E}{T}[/tex]

=>     [tex]P  =  \frac{0.02}{0.2696}[/tex]

=>     [tex]P  = 0.085 \  W [/tex]

Answer:

endorphins

Explanation:

Answer:

M V = m v        conservation of momentum (Caps-cannon  Small-projectile)

V = m / M * V = 2 / 2000 * 200 m/s = .2 m/s    recoil velocity of cannon

KE = 1/2 M V^2 = 2000 / 2 kg * (.2 m/s)^2  = 40 kg m^2/s^2 = 40 J

Answer:

Explanation:

The work done by an object can be found by using the formula

From the question

force = 290 N

distance = 5 m

We have

workdone = 290 × 5

We have the final answer as

Hope this helps you

(a) Differentiate the position vector to get the velocity vector:

r(t) = (3.00 m/s) t i - (4.00 m/s²) t² j + (2.00 m) k

v(t) = dr/dt = (3.00 m/s) i - (8.00 m/s²) t j

(b) The velocity at t = 2.00 s is

v (2.00 s) = (3.00 m/s) i - (16.0 m/s) j

(c) Compute the electron's position at t = 2.00 s:

r (2.00 s) = (6.00 m) i - (16.0 m) j + (2.00 m) k

The electron's distance from the origin at t = 2.00 is the magnitude of this vector:

||r (2.00 s)|| = √((6.00 m)² + (-16.0 m)² + (2.00 m)²) = 2 √74 m ≈ 17.2 m

(d) In the x-y plane, the velocity vector at t = 2.00 s makes an angle θ with the positive x-axis such that

tan(θ) = (-16.0 m/s) / (3.00 m/s)   ==>   θ ≈ -79.4º

or an angle of about 360º + θ ≈ 281º in the counter-clockwise direction.

Answer:

The angular acceleration is 2 rad/s².

Explanation:

Given that,

Rotational inertia = 1.0 kg m²

Torque = 2.0 Nm

We need to calculate the angular acceleration

Using formula of torque

[tex]\tau=I\alpha[/tex]

[tex]\alpha=\dfrac{\tau}{I}[/tex]

Where, I = moment of inertia

[tex]\tau[/tex] = torque

Put the value into the formula

[tex]\alpha=\dfrac{2.0}{1.0}[/tex]

[tex]\alpha=2\ rad/s^2[/tex]

Hence, The angular acceleration is 2 rad/s².

Answer: C

Explanation: Amplitude controls loudness, and frequency controls pitch. The more frequent the higher pitch.

The true statement regarding the two sounds is wave A has a lower pitch.

The pitch of a sound is sensation of the sound frequency.

A high pitch sound corresponds to a high frequency sound wave and a low pitch sound corresponds to low frequency.

Sound of the the same amplitude, have the same loudness.

Thus, the true statement regarding the two sounds is wave A has a lower pitch.

Learn more pitch of sound here: https://brainly.com/question/13679347

#SPJ2

Answer:

The potential energy is 367.5 J and power is 36.75 W.

Explanation:

Given that,

Mass of a crate, m = 15 kg

It is lifted to a height of 2.5 m

We need to find the potential energy of the crate after it is lifted. It is given by the formula as follows :

[tex]E=mgh\\\\E=15\ kg\times 9.8\ m/s^2\times 2.5\ m\\\\E=367.5\ J[/tex]

If time, t = 10 s, Power is given by :

[tex]P=\dfrac{E}{t}\\\\P=\dfrac{367.5}{10}\\\\P=36.75\ W[/tex]

So, the potential energy is 367.5 J and power is 36.75 W.

Answer:

μ_k = 0.851

Explanation:

We are given;

Mass of book; m_book = 4.7 kg

Horizontal force; F_horiz = 42 N

Distance; d = 0.85 m

Speed; v = 1 m/s

First of all let's find the acceleration using Newton's equation of motion;

v² = u² + 2ad

u is initial velocity and it's 0 m/s in this case.

Thus;

1² = (2 × 0.85)a

1 = 1.7a

a = 1/1.7

a = 0.5882 m/s²

Now, resolving forces along the vertical direction, we have;

W - N = 0

Thus,W = N

Where W is weight = mg and N is normal force

Thus; N = mg = 4.7 × 9.81 = 46.107 N

Now, resolving forces along the horizontal direction, we have;

F_horiz - ((μ_k)N) = ma

Where μ_k is coefficient of kinetic friction.

Thus;

42 - 46.107(μ_k) = 4.7 × 0.5882

42 - 46.107(μ_k) = 2.76454

μ_k = (42 - 2.76454)/46.107

μ_k = 0.851

Answer:

3.2

Explanation:

I hope that this helps! Have a good day!!

Answer:

You must travel at an average speed of 67.06 m/s to be on time to the lecture.

Explanation:

From the question, the total distance from your house to the science lecture is 75 miles.

Also, you get halfway there before you stop for a gas, that is, you have covered half of 75 miles, which 37.5 miles and you also have to cover 37.5 miles to get to the science lecture.

After filling up, you only have 15  minutes before the lecture starts,

To determine how fast you must drive to be on time to the lecture,

we will determine the average speed you need to travel.

From

Average speed = Distance / Time

Distance = 37.5 miles (Convert to meters)

(NOTE: 1 mile = 1609.344 meters)

Hence, 37.5 miles = 37.5 × 1609.344 miles = 60350.4 meters

∴ Distance = 60350.4 meters

Time = 15 minutes (Convert to seconds)

(NOTE: 1 minute = 60 seconds)

Hence, 15 minutes = 15 × 60 seconds = 900 seconds

Now, from

Average speed = Distance / Time

Average speed = 60350.4 m / 900 s

Average speed = 67.06 m/s

Hence, you must travel at an average speed of 67.06 m/s to be on time to the lecture.

Answer:

true b

Explanation:

They ask us to evaluate if the expressions are true

a) False. The concept of polarization refers to the direction of the oscillating electric field in a traveling wave, in this case the shocks cause the wave to disperse

b) True .. Yes, since no work is done inside the conductor, so all the load is on the surface

c) False. In electrostatic equilibrium the voltage must be the same everywhere

d) False. If the charges are positive point out

              If the charges are negative point inwards

e) False. If the charge is positive, the pattern is outward

               if negative largares points gavia inside.

Answer:

F = 47.6 N

Explanation:

       [tex]F = \frac{\Delta p}{\Delta t}[/tex]

       [tex]F_{wall} = \frac{\Delta p}{\Delta t} =\frac{(48.0 kg*(-1.06m/s)}{1.07s} = -47.6 N[/tex]

       ⇒ Fsk = 47.6 N (normal to the wall)

The amount of kinetic energy in an object can be increased by two ways:

The energy an object has as a result of motion is known as kinetic energy in physics. It is described as the effort required to move a mass-determined body from rest to the indicated velocity.

The body holds onto the kinetic energy it acquired during its acceleration until its speed changes. The body exerts the same amount of effort when slowing down from its current pace to a condition of rest.

Mathematically kinetic energy can be expressed as:

Kinetic energy = 1/2 × mass × speed²

Hence, the amount of kinetic energy in an object can be increased by two ways:

Learn more about kinetic energy here:

https://brainly.com/question/26472013

#SPJ2

Answer:

The momentum of the boat A is 10 kg.m/s.

Explanation:

Given;

velocity of the two boats, V = 1 m/s

mass of boat A, mₐ = 10 kg

mass of boat B, mb = 5 kg

Linear momentum is given by the product of mass and linear velocity.

The momentum of the boat A is given by;

Pₐ = mₐv

Pₐ = 10 x 1

Pₐ = 10 kg.m/s

Therefore, the momentum of the boat A is 10 kg.m/s.

Answer:

The force of forearm is 239.9 N

The force of elbow is 215.89 N

Explanation:

Suppose, When you lift an object by moving only your forearm, the main lifting muscle in your arm is the biceps. Suppose the mass of a forearm is 1.50 kg. If the biceps is connected to the forearm a distance [tex]d_{b}[/tex] 2.50 cm from the elbow, how much force [tex]F_{b}[/tex] must the biceps exert to hold a 950 g ball at the end of the forearm at distance dball J 36.0 cm from the elbow, with the forearm parallel to the floor? How much force [tex]F_{l}[/tex] must the elbow exert,

Given that,

Mass of forearm = 1.50 kg

Distance of forearm = 2.50 cm

Mass of ball = 950 g

Distance of ball = 36.0 cm

We need to calculate the force of forearm

Using balancing torque about elbow

[tex]F_{b}\times d_{b}=w_{f}\times\dfrac{d_{f}}{2}+w_{ball}\times d_{ball}[/tex]

Put the value into the formula

[tex]F_{b}\times 0.025= 1.50\times9.8\times\dfrac{0.36}{2}+0.95\times9.8\times0.36[/tex]

[tex]F_{b}=\dfrac{1.50\times9.8\times\dfrac{0.36}{2}+0.95\times9.8\times0.36}{0.025}[/tex]

[tex]F_{b}=239.9\ N[/tex]

We need to calculate the force of elbow

Using balancing force

[tex]F_{b}=F_{l}+w_{f}+w_{b}[/tex]

[tex]F_{l}=F_{b}-w_{f}-w_{b}[/tex]

Put the value into the formula

[tex]F_{l}=239.9-(1.50\times9.8)-(0.95\times9.8)[/tex]

[tex]F_{l}=215.89\ N[/tex]

Hence, The force of forearm is 239.9 N

The force of elbow is 215.89 N

Answer:

The voltage is   [tex]V =   0.993V_b[/tex]

Explanation:

From the question we are told that

   The time that has passed is  [tex]t = \frac{\tau}{2}[/tex]

 Here [tex]\tau[/tex] is know as the time constant

    The voltage of the  power source is   [tex]V_b[/tex]

Generally the voltage equation for charging a capacitor is mathematically represented as

       [tex]V =  V_b  [1 - e^{- \frac{t}{\tau} }][/tex]

=>   [tex]V =  V_b  [1 - e^{- \frac{\frac{\tau}{2}}{\tau} }][/tex]

=>   [tex]V =  V_b  [1 - e^{- \frac{\tau}{2\tau} }][/tex]

=>   [tex]V =  V_b  [1 - e^{- \frac{1}{2} }][/tex]

=>   [tex]V =   0.993V_b[/tex]    

Answer:

false

Explanation:

Answer:

t = 6.7 min.

Explanation:

        [tex]t = \frac{d}{v_{avg} } = \frac{8000 m}{20 m/s} = 400 s[/tex]

       [tex]400 s * \frac{1 min}{60 s} = 6.7 min.[/tex]

Explanation:

classical physics and modern physics.

Physics is the branch of science that deals with the interaction of energy and matter. Modern and Classical Physics are the two major branches of physics.

Physics is the discipline of science that investigates the structure of matter and how the universe's fundamental constituents interact. It investigates objects ranging from the very small to the entire universe using quantum mechanics and general relativity.

One of the most crucial physics topics is kinematics. Kinematics is the study of an object 's direction of travel. Kinematics is only concerned with the motion of an object.

There is a vertical and a horizontal component to two-dimensional projectile motion, such as that of a football or other thrown object.

Throwing a rock or kicking a ball produces a projectile pattern of motion that includes both a vertical and a horizontal component.

Thus, these can be the topics that require the knowledge of physics.

For more details regarding physics, visit:

https://brainly.com/question/28600368

#SPJ2

Answer:

The object has to have mass and speed

Explanation:

You can increase both speed and mass to increase the kinetic energy, hope this answers your question.

Happy Halloween!

Answer:

The options are not shown, so i will answer in a general way:

We can separate the problem in two cases.

The movement in the x-axis, that is unperturbed, so the particle will keep moving in the +x direction with the same speed.

The movement in the y-axis, as a constant force is applied, by the second Newton's law:

F = m*a

a = F/m = constant

v = a*t + v0

p = (a/2)*t^2 + v0*t + p0

Where v0 = initial velocity in the y-axis, p0 = initial position (in this case the origin) and t is the time. (In this case, these values really do not matter, i only want to show the general equations of movement in the y-axis)

We will also have a constant acceleration, which means that the velocity in this axis will be linear, and the position quadratic, then after the particle reaches the origin, it will start moving up and to the right, and the upward movement will increase in magnitude as time passes, a graph in the x-y plane would be something like:

Answer:

This question is incomplete

Explanation:

This question is incomplete. However, the formula for velocity is;

Velocity (in m/s) = distance/time

The distance the car covered in the completed question is divided by the difference in the time interval

The difference in the time interval will be = 1.5s - 1.0s = 0.5s

NOTE: the distance must be in meters or be converted to meters

Complete Question

The complete question is shown on the first uploaded image

Answer:

The equation is   [tex]c = \frac{1}{\sqrt{ \mu_o *  \epsilon_o} }[/tex]

The value of  c is [tex]c = 2.998 *10^{8} \  m/s  [/tex]

Explanation:

From the question we are told that

   Generally the equation that  relates the speed of light to other fundamental electromagnetic constants is

     [tex]c = \frac{1}{\sqrt{ \mu_o *  \epsilon_o} }[/tex]

Here  c is the speed of light

[tex]\mu_o[/tex] is the permeability of free space with value

    [tex]\mu_o = 4\pi *10^{-7} \ N/A^2[/tex]

and  [tex]\epsilon_o[/tex] is the permittivity of free space  with value  

      [tex]\epsilon_o  =  8.85*10^{-12} \ C/V \cdot m[/tex]

So

      [tex]c = \frac{1}{\sqrt{ 4\pi *10^{-7}  *  8.85*10^{-12}} }[/tex]

=>   [tex]c = 2.998 *10^{8} \  m/s  [/tex]

Answer:

444.99

Explanation:

Explanation:

C=A-B

=(4.00i+7.00j)-(5.00i-2.00j)

= -1.00i+9.00j

A.B=AxBx+AyBy

=(4 x 5)+(7 x -2)

=20-14

=6