A process occurs in which a system's potential energy increases while the environment does work on the system.

An object is released from rest at time t = 0 and falls through the air, which exerts a resistive force such that the accelerati

rosijanka [135]

Answer:

A) $\frac{g}{b}(1-e^{-bt})$

Explanation:

Since a = g - bv,

We can substitute a = dv/dt into the equation.

Then, the equation will be like dv/dt = g - bv.

So we got first order differential equation.

As known, v = 0 at t = 0, and v = g/b at t = ∞.

Since $\frac{dv}{dt}= g - bv = b( \frac{g}{b} - v)$ ⇒ $\frac{dv}{ \frac{g}{b} - v}= bdt$

So take the integral of both side.

$- ln (\frac{g}{b} - v) = bt + C$

Since for t=0, v = 0 ⇒ $C =- ln (\frac{g}{b})$

$v = \frac{g}{b} + e^{-bt-ln(\frac{g}{b})} = \frac{g}{b}- \frac{g}{b}e^{-bt} = \frac{g}{b}(1-e^{-bt})$

5 0

3 years ago

A box moves 1000 m horizontally as a force F 2000 N is applied downward. What is the work done on the box by F during the displa

stiks02 [169]

Answer:

D. OJ

Explanation:

5 0

3 years ago

A wire with a current of 3.40 A is to be formed into a circular loop of one turn. If the required value of the magnetic field at

Sloan [31]

Answer:

0.107 m

Explanation:

The magnetic field at the center of a current-carrying loop is given by

$B=\frac{\mu_0 I}{2r}$

where

$\mu_0$ is the vacuum permeability

I is the current

r is the radius of the loop

In this problem we have

I = 3.40 A is the current in the loop

$B=20 \mu T=20\cdot 10^{-6}T$ is the magnetic field at the centre of the loop

So, solving the formula for r we find

$r=\frac{\mu_0 I}{2B}=\frac{(12.56\cdot 10^{-7} H/m)(3.40 A)}{2(20\cdot 10^{-6} T)}=0.107 m$

7 0

2 years ago

How many changes can this undergo?Does it mean from this current state or how it can change.Please explain it to me.If you were

Fofino [41]

Let's assume this is a drawing of particles of a gas substance. This assumption is made upon the fact that these particles are not close and are represented in motion characteristic for gases. Gases can become solid by skipping the liquid phase. This process is called deposition. Also, a gas can become a liquid through the process of condensation as a result of energy loss at molecular level. Likewise, this is enabled thanks to heat loss or applied pressure.

5 0

3 years ago

An airplane is flying in a horizontal circle at a speed of 480 km/h (). If its wings are tilted at angle =40° to the horizontal

german

Answer:

$R = 2162 m$