A rescue plane spots a survivor 132 m directly below and releases an emergency kit with a parachute. If the package descends at a constant vertical acceleration of 6.89 m/s2 the initial plane horizontal speed was 86.9 m/s, how far away from the survivor will it hit the waves

Answer:

Look at explanation

Explanation:

a)Only force acting on the object is gravity, so a=-g (consider up to be positive)

use: v^2=v0^2+2a(y-y0)

plug in givens, at max height v=0

0=400-19.6(H)

Solve for H

H= 20.41m

b) Use: y=y0+v0t+1/2at^2

Plug in givens

0=0+20t-4.9t^2

solve for t

t=4.08 seconds

c) v=v0+at

v=20-39.984= -19.984m/s

Answer:

[tex]{ \bf{pythogras \: theorem :}} \\ \\ { \tt{ = \sqrt{ {9.6}^{2} + {18}^{2} } }} \\ = 20.4 \: cm[/tex]

Answer:

The gravitational force Asteroid A experiences is greater than the gravitational force Asteroid C experiences

Answer:

   P = 10135.6 Pa

Explanation:

For this exercise we use that the pressure varies with the height

           P = P₀ + ρ g h

where h is the height from the head to the heart, which is approximately

h = 40 cm = 0.40m  and P₀ is the head pressure P₀ = 6000 Pa

          P = 6000 + 1055 9.8 0.40

          P = 6000 + 4135.6

          P = 10135.6 Pa

Answer:

false

Explanation:

took the test

Answer:

[tex]\frac{dV}{dt}=21.21cm^3/min[/tex]

Explanation:

We are given that

[tex]PV^{1.4}=C[/tex]

Where C=Constant

[tex]\frac{dP}{dt}=-7KPa/minute[/tex]

V=420 cubic cm and P=99KPa

We have to find the rate at which the  volume increasing at this instant.

Differentiate w.r.t t

[tex]V^{1.4}\frac{dP}{dt}+1.4V^{0.4}P\frac{dV}{dt}=0[/tex]

Substitute the values

[tex](420)^{1.4}\times (-7)+1.4(420)^{0.4}(99)\frac{dV}{dt}=0[/tex]

[tex]1.4(420)^{0.4}(99)\frac{dV}{dt}=(420)^{1.4}\times (7)[/tex]

[tex]\frac{dV}{dt}=\frac{(420)^{1.4}\times (7)}{1.4(420)^{0.4}(99)}[/tex]

[tex]\frac{dV}{dt}=21.21cm^3/min[/tex]

Answer:

[tex]\dot V=2786.52~cm^3/min[/tex]

Explanation:

Given:

initial pressure during adiabatic expansion of air, [tex]P_1=99~kPa[/tex]

initial volume during the process, [tex]V_1=420~cm^3[/tex]

The adiabatic process is governed by the relation [tex]PV^{1.4}=C[/tex] ; where C is a constant.

Rate of decrease in pressure, [tex]\dot P=7~kPa/min[/tex]

Then the rate of change in volume, [tex]\dot V[/tex] can be determined as:

[tex]P_1.V_1^{1.4}=\dot P.\dot V^{1.4}[/tex]

[tex]99\times 420^{1.4}=7\times V^{1.4}[/tex]

[tex]\dot V=2786.52~cm^3/min[/tex]

[tex]\because P\propto\frac{1}{V}[/tex]

[tex]\therefore[/tex] The rate of change in volume will be increasing.

Answer:

0.5766422350752*10^-24 N

Explanation:

Couloumb's law states that states that there is an electrical force acting on 2 static charges. The magnitude is directly proportional to the product of the 2 charges.

Strength of electrons : q1 = q2 = 1.602 x 10-19. C

Substitute and solve:

F = (9*10^9)(1.602 x 10-19)(1.602 x 10-19) / (0.02)^2

Done.

Answer:

The answer is C. Isolated System

Answer:

C. Isolated system

Explanation :

∵According to law of  conservation of momentum ,In an isolated system ,the total momentum remains conserved.

Explanation:

Let T is the period of a pendulum. The SI unit of time is seconds (s).

It depends on the acceleration of gravity, g, and the length of the pendulum, l.

The SI unit of acceleration of gravity, g and the length of the pendulum, l are m/s² and m respectively.

If we divide m and m/s², we left with s². If the square root of s² is taken, we get s only i.e. the SI unit of period of a pendulum.

So,

[tex]T\propto \sqrt{\dfrac{l}{g}}[/tex]

Hence, this is the required solution.

Answer:

True.

Explanation:

If the sum of the external forces on an object is zero, then the sum of the external torques on it  must also be zero.

The net external force and the net external torque acting on the object have to be zero for an object to be in mechanical equilibrium.

Hence, the given statement is true.

Answer:

f = 347.08 N

Explanation:

The frictional force exerted by the floor on the refrigerator is given as follows:

[tex]f = \mu R = \mu W[/tex]

where,

f = frictional force = ?

μ = coefficient of static friction = 0.58

W = Weight of refrigerator = mg

m = mass of refrigerator = 61 kg

g = acceleration due to gravity = 9.81 m/s²

Therefore,

[tex]f = \mu mg\\f = (0.58)(61\ kg)(9.81\ m/s^2)\\[/tex]

f = 347.08 N

Answer:

A(predicts an organisms ability to adapt to its enviroment, it is not a fact that each organization can adapt)

Explanation:

Answer:

18

Explanation:

I'm pretty sure I got it right

Answer:

[tex]\alpha=-3.01dB[/tex]

Explanation:

From the question we are told that:

Sound level intensity

 [tex]\triangle I=40dB-80dB[/tex]

Generally the equation for  intensity level  is mathematically given by

 [tex]\alpha=10log_{10}(I/I_x)dB[/tex]

Where

 I= Intensity measured

 [tex]I_x=Threshold\ of\ audibility[/tex]

 [tex]I_x= 10-12 W / m2[/tex]

 [tex]\alpha= 10 log10 \frac{I_1}{I_x} - 10 log10 \frac{}I_2{I_x}[/tex]

 [tex]\alpha= 10 log10 \frac{I_1}{I_2}[/tex]

 [tex]\alpha=10 log10\frac{40}{80}[/tex]

 [tex]\alpha=-3.01dB[/tex]

Answer:

a)   W_total = mg (2h + d)   , b)     E_total = - mg (h + d)

Explanation:

a) We must solve this problem in two parts, the first for the accelerated movement and the second for the movement with constant speed

Let's look for work for the part that is in free fall

        y = y₀ + v₀ t - ½ g t²

when he jumps out of a plane his vertical speed is zero

        y =y₀ - ½ g t²

        dy = 0 - ½ g 2t dt

the work in this first part is

        W₁ = ∫ F dy

        W₁ = mg ∫ g t dt

        W₁ = m g² t² / 2

the time it takes to travel the distance y₀-y = h is

         y₀-y = ½ g t²

         t =[tex]\sqrt{2h/g}[/tex]

we substitute

          W₁ = m g² 2h / g

          W₁ = m g 2h

now we look for the work for the part with constant speed

since the velocity is constant let's use the uniform motion ratio

          W₂ = F d

           W₂ = mg d

the total work is

           W_total = W₁ + W₂

           W_total = 2mgh + m gd

           W_total = mg (2h + d)

b) The change in gravitational potential energy

           U = mg Δy

in the part with accelerated movement

           U₁ = mg h

in the part with uniform movement

            U₂ = mg d

the total potential energy is

           E_total = U₁ + U₂

           E_total = - mg (h + d)

Answer:

The expected radius of the Earth is 3.883 meters.

Explanation:

The formula for the escape speed is derived from Principle of Energy Conservation and knowing that rocket is initially at rest on the surface of the Earth and final energy is entirely translational kinetic, that is:

[tex]U = K[/tex] (1)

Where:

[tex]U[/tex] - Gravitational potential energy, in joules.

[tex]K[/tex] - Translational kinetic energy, in joules.

Then, we expand the formula by definitions of potential and kinetic energy:

[tex]\frac{G\cdot M\cdot m}{r} = \frac{1}{2}\cdot m \cdot v^{2}[/tex] (2)

Where:

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

[tex]M[/tex] - Mass of the Earth. in kilograms.

[tex]m[/tex] - Mass of the rocket, in kilograms.

[tex]r[/tex] - Radius of the Earth, in meters.

[tex]v[/tex] - Escape velocity, in meters per second.

Then, we derive an expression for the escape velocity by clearing it within (2):

[tex]\frac{GM}{r} = \frac{1}{2}\cdot v^{2}[/tex]

[tex]v = \sqrt{\frac{2\cdot G \cdot M}{r} }[/tex] (3)

If we know that [tex]v = \frac{1}{21}\cdot c[/tex], [tex]c = 3\times 10^{8}\,\frac{m}{s}[/tex], [tex]M = 5.94\times 10^{24}\,kg[/tex], [tex]G = 6.67\times 10^{-11}\,\frac{m^{3}}{kg\cdot s^{2}}[/tex] and [tex]M = 5.94\times 10^{24}\,kg[/tex], then the expected radius of the Earth is:

[tex]\frac{GM}{r} = \frac{1}{2}\cdot v^{2}[/tex]

[tex]r = \frac{2\cdot G \cdot M}{v^{2}}[/tex]

[tex]r = \frac{2\cdot \left(6.67\times 10^{-11}\,\frac{m^{3}}{kg\cdot s^{2}} \right)\cdot (5.94\times 10^{24}\,kg)}{\left[\frac{1}{21}\cdot \left(3\times 10^{8}\,\frac{m}{s} \right) \right]^{2}}[/tex]

[tex]r = 3.883\,m[/tex]

The expected radius of the Earth is 3.883 meters.

Explanation:

Conservation of energy, principle of physics according to which the energy of interacting bodies or particles in a closed system remains constant

hope it is helpful to you

Answer:

r = 20.22 m

Explanation:

Given that,

Charge,[tex]q=2.5\times 10^{-6}\ C[/tex]

Electric field, [tex]E=55\ N/C[/tex]

We need to find the distance. We know that, the electric field a distance r is as follows :

[tex]E=\dfrac{kq}{r^2}\\\\r=\sqrt{\dfrac{kq}{E}}\\\\r=\sqrt{\dfrac{9\times 10^9\times 2.5\times 10^{-6}}{55}}\\\\r=20.22\ m[/tex]

So, the required distance is 20.22 m.

Explanation:

Given that,

Amplitude, A = 2.5 nm

Wavelength,[tex]\lambda=1.8\ m[/tex]

The speed of the wave, v = 36 m/s

At time t = 0 the left end of the string has its maximum upward displacement.

(a) Let f is the frequency. So,

[tex]f=\dfrac{v}{\lambda}\\\\f=\dfrac{36}{1.8}\\\\f=20\ Hz[/tex]

(b) Angular frequency of the wave,

[tex]\omega=2\pi f\\\\=2\pi \times 20\\\\=125.7\ rad/s[/tex]

(c) The wave number of the wave[tex]=\dfrac{1}{\lambda}[/tex]

[tex]=\dfrac{1}{1.8}\\\\=0.56\ m^{-1}[/tex]

Answer:

The maximum height risen by the bullet-baseball system after the collision is 81.76 m.

Explanation:

Given;

mass of the bullet, m₁ = 0.033 kg

mass of the baseball, m₂ = 0.15 kg

initial velocity of the bullet, u₁ = 222 m/s

initial velocity of the baseball, u₂ = 0

let the common final velocity of the system after collision = v

Apply the principle of conservation of linear momentum to determine the common final velocity.

m₁u₁  +  m₂u₂  = v(m₁  + m₂)

0.033 x 222   +  0.15 x 0     = v(0.033 + 0.15)

7.326  =  v(0.183)

v = 7.326 / 0.183

v = 40.03 m/s

Let the height risen by the system after collision = h

Initial velocity of the system after collision = Vi = 40.03 m/s

At maximum height, the final velocity, Vf = 0

acceleration due to gravity for upward motion, g = -9.8 m/s²

[tex]v_f^2 = v_i^2 +2gh\\\\0 = 40.03^2 - (2\times 9.8)h\\\\19.6h = 1602.4\\\\h = \frac{1602.4}{19.6} \\\\h = 81.76 \ m[/tex]

Therefore, the maximum height risen by the bullet-baseball system after the collision is 81.76 m.

Answer:

Explanation:

a )

Magnetic field inside solenoid B = μ₀ NI ,

μ₀ = 4π x 10⁻⁷ ; N is no of turns per meter length in solenoid and I is current B=  4π x 10⁻⁷ x 30 x 10² x 15

= .0565 T .

Force on each side of square loop = B i L

B is external magnetic field , i is current in loop and L is length of side

Force on each side of square loop = .0565 x .24 x 2 x 10⁻²

= 2.7 x 10⁻⁴ N .

b )

Torque on the loop =  F x d

F is force on one side , d is distance between two sides , that is side of the square loop

= 2.7 x 10⁻⁴ x 2 x 10⁻² N.m

= 5.4  x 10⁻⁶ N.m .

Answer:

t= 100s

Explanation:

use v=v0+at

plug in givens and solve for t

30=20+0.1*t

t= 100s

Answer:

false.

Explanation:

Ok, we define average velocity as the sum of the initial and final velocity divided by two.

Remember that the velocity is a vector, so it has a direction.

Then when she goes from the 1st end to the other, the velocity is positive

When she goes back, the velocity is negative

if both cases the magnitude of the velocity, the speed, is the same, then the average velocity is:

AV = (V + (-V))/2  = 0

While the average speed is the quotient between the total distance traveled (twice the length of the pool) and the time it took to travel it.

So we already can see that the average velocity will not be equal to half of the average speed.

The statement is false

Answer:

Approximately 4.029 A

Explanation:

We can use the formula that the B field of a few loops all with current in same direction is permeability of free space (mu)* current * Number or loops divided by 2*radius. You are given B field, radius(convert into meters), number of loops and mu is 4pi * 10^-7. Solve for current and you get 4.029 Amperes.

First of all, both are not a single sheet of atom. There are many layers of atoms, so the empty part gets beside each other, so there are less empty part. Secondly, there are so many atoms that the probability that they will have empty space at the same place necessary, is negligible.

This was something from logic.

The reason I was taught in my class was that only a limited number of electrons can be in a given orbit, so atoms cannot overlap each other.

Answer:

The pressure is 2505 Pa.  

Explanation:

Height, h = 1.5 m

density of blood, d = 1000 kg/cubic meter

Gravity, g = 1.67 m/s^2

let the pressure is P.  

The pressure due to the fluid is given by

P = h d g

P = 1.5 x 1000 x 1.67

P = 2505 Pa

Answer:

[tex]M_2=0.79kg[/tex]

Explanation:

From the question we are told that:

Period [tex]T=0.517s[/tex]

Trial 1

Spring constant [tex]\mu=117N/m[/tex]

Period [tex]T_1=0.37[/tex]

Mass [tex]m=0.400kg[/tex]

Trial 2

Period [tex]T_2=0.52[/tex]

Generally the equation for Spring Constant  is mathematically given by

\mu=\frac{4 \pi^2 M}{T^2}

Since

[tex]\mu _1=\mu_2[/tex]

Therefore

[tex]\frac{4 \pi^2 M_1}{T_1^2}=\frac{4 \pi^2 M_2}{T_2^2}[/tex]

[tex]M_2=M_1*(\frac{T_2}{T_1})^2[/tex]

[tex]M_2=0.400*(\frac{0.52}{0.37}})^2[/tex]

[tex]M_2=0.79kg[/tex]

Answer:

a) Δp = -2.0 kgm / s,  b)   Δp = -4 kg m / s

Explanation:

In this exercise the change in moment of a ball is asked in two different cases

a) clay ball, in this case the ball sticks to the door and we have an inelastic collision where the final velocity of the ball is zero

         Δp = p_f - p₀

         Δp = 0 - m v₀

         Δp = - 0.100 20

         Δp = -2.0 kgm / s

b) in this case we have a bouncing ball, this is an elastic collision, as the gate is fixed it can be considered an object of infinite mass, therefore the final speed of the ball has the same modulus of the initial velocity, but address would count

         v_f = - v₀

        Δp = p_f -p₀

        Δp = m v_f - m v₀

        Δp = m (v_f -v₀)

        Δp = 0.100 (-20 - 20)

        Δp = -4 kg m / s