Earths lithosphere is made up of large plates that are in constant motion

When air resistance balances the weight of an object that is falling, the velocity _____.

miskamm [114]

Decreases. Air resistance will slow a falling object to its terminal velocity, placing a limit on its acceleration.

5 0

3 years ago

An airliner arrives at the terminal, and its engines are shut off. The rotor of one of the engines has an initial clockwise angu

Ilia_Sergeevich [38]

(a) 1200 rad/s

The angular acceleration of the rotor is given by:

$\alpha = \frac{\omega_f - \omega_i}{t}$

where we have

$\alpha = -80.0 rad/s^2$ is the angular acceleration (negative since the rotor is slowing down)

$\omega_f$ is the final angular speed

$\omega_i = 2000 rad/s$ is the initial angular speed

t = 10.0 s is the time interval

Solving for $\omega_f$ , we find the final angular speed after 10.0 s:

$\omega_f = \omega_i + \alpha t = 2000 rad/s + (-80.0 rad/s^2)(10.0 s)=1200 rad/s$

(b) 25 s

We can calculate the time needed for the rotor to come to rest, by using again the same formula:

$\alpha = \frac{\omega_f - \omega_i}{t}$

If we re-arrange it for t, we get:

$t = \frac{\omega_f - \omega_i}{\alpha}$

where here we have

$\omega_i = 2000 rad/s$ is the initial angular speed

$\omega_f=0$ is the final angular speed

$\alpha = -80.0 rad/s^2$ is the angular acceleration

Solving the equation,

$t=\frac{0-2000 rad/s}{-80.0 rad/s^2}=25 s$

6 0

3 years ago

What best describes a sound wave? transverse and electromagnetic longitudinal and mechanical longitudinal and electromagnetic tr

GalinKa [24]

Sound needs medium to travel and it can not travel without medium

so sound wave is a travelling wave

now we also know that sound wave propagate in form of rarefaction and compression.

So all medium particles travel in the direction of wave only

so it is a longitudinal wave also

so correct answer will be

<em>mechanical longitudinal </em>

7 0

3 years ago

Read 2 more answers

a spring with a constant of 80N/m is stretched by a force of 240N. how much the displacement of the spring from equilibrium?

Inessa05 [86]

Answer:

1200N/m

Explanation:

given parameters:

force on the motorcycle spring is 240N

Extension 2cm or 0.02m

unknown _

spring constant:

:?

solution:

to a spring a force applied is given as :

f=ke

f is applied as force

k is spring constant

e is the Extension

240= kx0.02

k=1200N/m

8 0

2 years ago

Based on the data given, in what direction will the car accelerate?

skad [1K]

Vertical forces:
There is a force of 579N acting upward, and a force of 579N
acting downward.
The vertical forces are balanced ... they add up to zero ...
so there's no vertical acceleration.
Not up, not down.

Horizontal forces:
There is a force of 487N acting to the left, and a force of 632N
acting to the right.
The net horizontal force is

(487-left + 632-right) - (632-right - 487-right) = 145N to the right.

The net force on the car is all to the right.
The car accelerates to the right.

7 0

2 years ago