Please help calculate them A-f please very urganr

Car A is traveling west at 40 mi/h and car B is traveling north at 40 mi/h. Both are headed for the intersection of the two road

Gwar [14]

Explanation:

It is given that,

$\frac{dx}{dt}$ = -40 mi/h, $\frac{dx}{dt}$ = -40 mi/h

The negative sign indicates that x and y are decreasing.

We have to find $\frac{dz}{dt}$ . Equation for the given variables according to the Pythagoras theorem is as follows.

$z^{2} = x^{2} + y^{2}$

Now, we will differentiate each side w.r.t 't' as follows.

$2z\frac{dz}{dt} = 2x\frac{dx}{dt} + 2y\frac{dy}{dt}$

or, $\frac{dz}{dt} = \frac{1}{z}(x\frac{dx}{dt} + y\frac{dy}{dt})$

So, when x = 4 mi, and y = 3 mi then z = 5 mi.

As, $\frac{dz}{dt} = \frac{1}{z}(x\frac{dx}{dt} + y\frac{dy}{dt})$

= $\frac{1}{5}(4 \times (-40) + 3 \times (-40))$

= $\frac{-140 - 120}{5}$

= 52

Thus, we can conclude that the cars are approaching at a rate of 52 mi/h.

7 0

3 years ago

ARRANGE THE STEPS IN ORDER TO DESCRIBE WHAT HAPPENS TO A GAS WHEN IT COOLS

vredina [299]

What happens to has when it cools is ...
Step 1) They will start to form liquids, like condensation.
Step 2) As liquids cool, they will turn into solids.
Step 3) As solids cool, they become more stable and solid.

3 0

3 years ago

Write an expression for a harmonic wave with an amplitude of 0.19 m, a wavelength of 2.6 m, and a period of 1.2 s. The wave is t

zlopas [31]

Answer:

$y = 0.19 sin(5.23 t - 2.42x + \frac{\pi}{2})$

Explanation:

As we know that the wave equation is given as

$y = A sin(\omega t - k x + \phi_0)$

now we have

$A = 0.19 m$

$\lambda = 2.6 m$

so we have

$k = \frac{2\pi}{\lambda}$

$k = \frac{2\pi}{2.6}$

$k = 2.42 per m$

also we have

$T = 1.2 s$

so we have

$\omega = \frac{2\pi}{T}$

$\omega = \frac{2\pi}{1.2}$

$\omega = 5.23 rad/s$

now we know that at t = 0 and x = 0 wave is at y = 0.19 m

so we have

$\phi_0 = \frac{\pi}{2}$

so we have

$y = 0.19 sin(5.23 t - 2.42x + \frac{\pi}{2})$

6 0

3 years ago

Kate gathered 3 of the same size made of different materials: glas, clear plastic, and aluminum painted black. She placed on the

Anestetic [448]

Answer:

To relate the type of box material to the warmth inside the box 

Explanation:

3 boxes are made with three different materials glass, plastic and Aluminium. Thermal conductivity is different for different materials. thermal conductors allow easy flow of heat through them and insulators allow minimal or no flow of heat through them.

Thus the amount by which an object gets heated up depends on the value of its conductivity. In this experiment, glass and plastic are insulators and aluminium is a conductor. Among glass and plastic, plastic is a better insulator.

Thus the heat contained in the boxes will be of the order Aluminium>glass>plastic.

3 0

3 years ago

An engine takes in 2400 J of heat, and rejects 1880 J of heat into the air. What is the efficiency of the engine? (No Unit)

Galina-37 [17]

Answer:

.2166 repeating or 21.66% repeating

Explanation:

In attached image

8 0

3 years ago